Sign in with
Sign up | Sign in
Your question

Volume control at the speaker?

Last response: in Home Audio
Share
August 2, 2005 3:25:33 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

In a distributed audio system in a residence, how can volume control in each
room be accomplished.

I realize that it's more complex than just putting a potentiometer in the
speaker leads.

Is this accomplished via 70v distribution system (ie, high-impedance
amplifier output)?

Or is some kind of acceptable variable attenuation possible in each room?

Google turns up L-pads. If I understand, an L-pad keeps 8-ohm impedance on
the line from the amplifier, while providing an attenuated signal to the
speaker.

As long as it is properly chosen, are there any cautions I should know about
installing an L-pad for each pair of speakers in a room?

Are L-pads reliable (no noise, etc.)? Brands to recommend? Or avoid?

Other ideas? Speak your peace.

Thanks,
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group

More about : volume control speaker

Anonymous
August 2, 2005 11:21:30 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

On Mon, 1 Aug 2005 23:25:33 -0700, DaveC <me@privacy.net> wrote:

>In a distributed audio system in a residence, how can volume control in each
>room be accomplished.
>
>I realize that it's more complex than just putting a potentiometer in the
>speaker leads.
>
>Is this accomplished via 70v distribution system (ie, high-impedance
>amplifier output)?
>
>Or is some kind of acceptable variable attenuation possible in each room?
>
>Google turns up L-pads. If I understand, an L-pad keeps 8-ohm impedance on
>the line from the amplifier, while providing an attenuated signal to the
>speaker.
>
>As long as it is properly chosen, are there any cautions I should know about
>installing an L-pad for each pair of speakers in a room?
>
>Are L-pads reliable (no noise, etc.)? Brands to recommend? Or avoid?
>
>Other ideas? Speak your peace.
>

Strictly speaking, L- Pads are fixed attentuators that match different
impedances.

What you want is a variable attenuator pad that will keep the
impedance (as seen by your amp) constant (commonly 8 ohms but it can
vary) as you vary the volume. Additionally, the controller has to be
able to handle the power being applied to your speaker and may be
ganged together for a stereo application.

No affiliation, but here is a link to one such product.

http://www.hometech.com/audio/volume.html

70 V distribution systems are used for PA systems (music and paging)
where there are particularly long runs with multiple speakers.

With a home audio 8 ohm speaker system, you can't just keep putting
parallel speakers on the line as each unit will lower the load
impedance and you will very quickly get to the point where you are
overloading your amplifier.

Beachcomber
Anonymous
August 2, 2005 11:22:27 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"DaveC" <me@privacy.net> wrote in message
news:0001HW.BF145FED002D3F30F02845B0@news.readfreenews.net...
> In a distributed audio system in a residence, how can volume control in
> each
> room be accomplished.

**There are a bunch of methods. The best is to distribute the music, via
line level (balanced) cables and amplifiy in each room. There are many more
methods, which are generally inferior.

>
> I realize that it's more complex than just putting a potentiometer in the
> speaker leads.

**Not necessarily. It depends on how much quality you are prepared to
sacrifice.

>
> Is this accomplished via 70v distribution system (ie, high-impedance
> amplifier output)?

**It can be. If you want to increase cost and throw away any chance at good
sound quality.

>
> Or is some kind of acceptable variable attenuation possible in each room?

**That is one way to do it. Quality will be sacrificed, however.

>
> Google turns up L-pads. If I understand, an L-pad keeps 8-ohm impedance on
> the line from the amplifier, while providing an attenuated signal to the
> speaker.
>
> As long as it is properly chosen, are there any cautions I should know
> about
> installing an L-pad for each pair of speakers in a room?

**Not really. Just be aware that the L-pad needs to be able to cope with the
maximum output of your amplifier. They can get very hot.

>
> Are L-pads reliable (no noise, etc.)?

**If the power is kept to reasonable levels (say: around 10-15 Watts
AVERAGE), they can last a few years.

> Brands to recommend? Or avoid?

**They all come out of Asia and porbably from the same factory. Just look
for the biggest, heaviest one you can find. That would probably be around
70-80mm diameter.

>
> Other ideas? Speak your peace.

**Many surround sound receivers employ a second zone system, which has power
amps dedicated for this purpose. That would be a good, economical choice.


--
Trevor Wilson
www.rageaudio.com.au
Related resources
Anonymous
August 2, 2005 1:08:33 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

It can also depend on whether the driving amp is a tube or semiconductor
type. The general rule of thumb is that tube amps don't like open circuits
( or anything in between ) across their outputs whilst semiconductor types
don't like shorts ( or anything in between ). By this, I mean that if a tube
amp is designed to deliver its rated power into say 16 ohms, then it won't
like having 50 ohms across it when you wind the wick up. Likewise, a
semiconductor amp ( transistors, ICs or STK hybrids ) won't like 2 ohms
across it, if it's designed to run into an 8 ohm load.

So, to run several sets of speakers, each adjustable, from one amp, it is
not a problem to put a wirewound pot in series with each speaker, assuming
that you are running a semiconductor amp. You can calculate the total load
easily by series addition, and ohms law. It's not quite right, as the '
ohmage ' quoted for a speaker, is its impedance at a particular frequency,
not its DC resistance, but near enough.

I would suggest using series resistors as well, to balance up the levels in
each room, and still leave a good adjustment range, as well as making sure
that the whole network cannot drop below the minimum load impedance before
the amp is being overloaded.

So let's say you are going to feed out to 5 rooms and use some 8 ohm
speakers that you've already got. The quoted minimum load impedance for your
semiconductor amp, is 8 ohms. If you just hook them all up in parallel, the
impedance presented to the amp will be 8/5 or 1.6 ohms - clearly an
overload.

Now change things so that at each speaker, you have a 22 ohm wirewound
resistor, in series with a 22 ohm w/w pot, hooked as a variable resistor, in
series with the 8 ohms of the speaker. With the pot at minimum resistance
( maximum audio ), each speaker will represent 30 ohms. So with all 5 rooms
set like this, the total paralleled load presented to the amp, would be 30/5
or 6 ohms. Unless you're going to play drum and bass at full volume, then by
the time you've added in a bit of cable resistance, your amp is not going to
mind this slight reduction in the minimum presented impedance.

Now turn each speaker to minimum vol ( maximum pot resistance ) Each speaker
will now be 22 ohms + 22 ohms + 8 ohms = 52 ohms. Parallel all these up, and
the impedance presented to the amp will be 52/5 or about 10 ohms.

You would set all this up by setting each pot to about half way, then
setting the amp volume control to get the desired level in the ' loudest '
room. The other rooms can then be adjusted down to the desired levels, but
could also still be adjusted above the loudest room if that became a
requirement. If the quieter rooms are still too loud with the pots at max
resistance, then just go for a higher value resistor until you reach the
level you want, bearing in mind that the higher you go with the resistor,
the less range the pot will have if you keep with the same value.

The best thing is to try it in the garage or wherever first. A few different
values of resistor and pot to play with, bought from your local Radio Shack
store, will be a lot cheaper and easier than getting special pads. The
values I've used are just to make the math easy to understand. If you follow
the principle, you should be able to adapt it. 22 ohms is probably a good
starting point though. It's hard to calculate a definitive power rating for
the pots and R's because it depends on many factors, but 3 watt wirewound or
cermet pots would probably be ok, with 3 or 5 watt resistors. Just try it
out and see if they get more than ' 3 watts hot '. Assuming that they don't,
then they will last for ever, not just a few years.

Finally, by presenting something other than the design impedance to the
driving amp's output, audio enthusiasts will tell you that you are
compromising the audio quality. Whilst this is strictly true if you start
looking at damping factors and other such esoteric quantities, I defy Joe
Average-Listner to hear anything untoward.

Geoff


"DaveC" <me@privacy.net> wrote in message
news:0001HW.BF145FED002D3F30F02845B0@news.readfreenews.net...
> In a distributed audio system in a residence, how can volume control in
> each
> room be accomplished.
>
> I realize that it's more complex than just putting a potentiometer in the
> speaker leads.
>
> Is this accomplished via 70v distribution system (ie, high-impedance
> amplifier output)?
>
> Or is some kind of acceptable variable attenuation possible in each room?
>
> Google turns up L-pads. If I understand, an L-pad keeps 8-ohm impedance on
> the line from the amplifier, while providing an attenuated signal to the
> speaker.
>
> As long as it is properly chosen, are there any cautions I should know
> about
> installing an L-pad for each pair of speakers in a room?
>
> Are L-pads reliable (no noise, etc.)? Brands to recommend? Or avoid?
>
> Other ideas? Speak your peace.
>
> Thanks,
> --
> Please, no "Go Google this" replies. I wouldn't
> ask a question here if I hadn't done that already.
>
> DaveC
> me@privacy.net
> This is an invalid return address
> Please reply in the news group
>
Anonymous
August 2, 2005 3:15:48 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

I did this in my home using NXG Impedance matching volume controls ( part
number NX-VCM80) which you can get on EBay for under $20 each this device
allows up to 8 sets of speakers to be connected to a receiver.It has taps
based on how many you are using which allow too to present a constant
impedance to the receiver. They have 12 steps of attenuation which is plenty
for me
hope this helps
Bob
"DaveC" <me@privacy.net> wrote in message
news:0001HW.BF145FED002D3F30F02845B0@news.readfreenews.net...
> In a distributed audio system in a residence, how can volume control in
> each
> room be accomplished.
>
> I realize that it's more complex than just putting a potentiometer in the
> speaker leads.
>
> Is this accomplished via 70v distribution system (ie, high-impedance
> amplifier output)?
>
> Or is some kind of acceptable variable attenuation possible in each room?
>
> Google turns up L-pads. If I understand, an L-pad keeps 8-ohm impedance on
> the line from the amplifier, while providing an attenuated signal to the
> speaker.
>
> As long as it is properly chosen, are there any cautions I should know
> about
> installing an L-pad for each pair of speakers in a room?
>
> Are L-pads reliable (no noise, etc.)? Brands to recommend? Or avoid?
>
> Other ideas? Speak your peace.
>
> Thanks,
> --
> Please, no "Go Google this" replies. I wouldn't
> ask a question here if I hadn't done that already.
>
> DaveC
> me@privacy.net
> This is an invalid return address
> Please reply in the news group
>
Anonymous
August 2, 2005 3:22:29 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"DaveC" <me@privacy.net> wrote in message
news:0001HW.BF145FED002D3F30F02845B0@news.readfreenews.net

> In a distributed audio system in a residence, how can
> volume control in each room be accomplished.

(1) Separate amp at each location, not totally impractical
in these days when you can get a pertty fair 100 wpc amp for
under $80 if you look around.

(2) Transformer-type stepped volume controls. Ironically
they are around $30 each, so you're talking a bit less than
half the price of the receiver.

http://www.hometech.com/audio/volume.html
August 2, 2005 3:22:30 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Thus spake Arny Krueger:

> (1) Separate amp at each location, not totally impractical
> in these days when you can get a pertty fair 100 wpc amp for
> under $80 if you look around.

Sources for small amplifiers? Place in wall? Attic?

Google turns up so many amps, but are stereo system component types.

Thanks,
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group
August 2, 2005 3:22:31 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Is there a wireless solution to distributing audio throughout a residence to
8 rooms? Digital?

Something similar to wireless computer networking...

Thanks,
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group
Anonymous
August 2, 2005 4:23:02 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"DaveC" <me@privacy.net> wrote in message
news:0001HW.BF14E559004C84AEF02845B0@news.readfreenews.net
> Thus spake Arny Krueger:
>
>> (1) Separate amp at each location, not totally
>> impractical in these days when you can get a pertty fair
>> 100 wpc amp for under $80 if you look around.

> Sources for small amplifiers? Place in wall? Attic?

http://cgi.ebay.com/Amplifier-module-with-LM3886-for-Ga...

It needs a pair of 24 volt transformers, and here are some
candidates at about $12 each:

http://www.action-electronics.com/trnsfrmr.htm


> Google turns up so many amps, but are stereo system
> component types.

Those too, including receivers.
Anonymous
August 2, 2005 8:06:39 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

In article <0001HW.BF145FED002D3F30F02845B0@news.readfreenews.net>,
DaveC <me@privacy.net> wrote:
> In a distributed audio system in a residence, how can volume control in
> each room be accomplished.

> I realize that it's more complex than just putting a potentiometer in
> the speaker leads.

> Is this accomplished via 70v distribution system (ie, high-impedance
> amplifier output)?

You can often cludge together a system using 100 volt line transformers on
a normal amp, and use the power output taps via a switch to give some
control of level. Not ideal, but any form of resistive system will sound
worse.

But a far better way is to have an amp per pair of speakers, and feed that
at line level.

--
*OK, who stopped payment on my reality check?

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.
August 2, 2005 8:06:40 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Thus spake Dave Plowman (News):

> You can often cludge together a system using 100 volt line transformers on
> a normal amp, and use the power output taps via a switch to give some
> control of level. Not ideal, but any form of resistive system will sound
> worse.

You being in the UK, I presume you mean 240:100v line transformers, yes? In
the USofA this would be half that: 120:50v transformers, yes?

Thanks,
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group
August 2, 2005 8:06:41 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Thus spake dpierce@cartchunk.org:

> There is a means of distributing high-level audio (speaker level)
> using impedance matching transformers. Two different level conventions
> exist: 70 volt and 100 volt. Matching transformers are provided at
> each speaker and are used to determine how much power that speaker
> can get. Some transformers have switchable taps that allow adjusting
> level.

Ah, yes. I'd known about 70v, hadn't heard of 100v.

Thanks,
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group
Anonymous
August 2, 2005 8:39:39 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

In article <0001HW.BF14EABB004DC7B6F04075B0@news.readfreenews.net>,
me@privacy.net says...
>
>Is there a wireless solution to distributing audio throughout a residence to
>8 rooms? Digital?
>
>Something similar to wireless computer networking...
>
>Thanks,


Yamaha makes a system called MusicCAST that does this. Has a hard
drive, stores 1,000 CD's in MP3 format or 100 in original format.
My son sells these in his audio store. See Yamaha.com.

JC the elder
Anonymous
August 2, 2005 8:57:25 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

In article <0001HW.BF14E25E004BD1F0F02845B0@news.readfreenews.net>,
DaveC <me@privacy.net> wrote:
> > You can often cludge together a system using 100 volt line
> > transformers on a normal amp, and use the power output taps via a
> > switch to give some control of level. Not ideal, but any form of
> > resistive system will sound worse.

> You being in the UK, I presume you mean 240:100v line transformers, yes?
> In the USofA this would be half that: 120:50v transformers, yes?

No - 100 volt line as used in PA systems for long runs to speakers, etc.
You use a transformer to match a normal low impedance speaker to the
'line' and use the turns ratio to set the power going in and therefore the
level. With this method you can hang as many speakers across one amp as
you want - up to its rated output - unlike paralleling low impedance
speakers across a normal amp. Most such transformers will have taps for
several different output settings, so can also be used to control level.

--
*Why is it that doctors call what they do "practice"?

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.
Anonymous
August 2, 2005 9:23:33 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"DaveC" <me@privacy.net> wrote in message
news:0001HW.BF145FED002D3F30F02845B0@news.readfreenews.net...
> In a distributed audio system in a residence, how can volume control in
> each
> room be accomplished.
>
> I realize that it's more complex than just putting a potentiometer in the
> speaker leads.
>
> Is this accomplished via 70v distribution system (ie, high-impedance
> amplifier output)?
>
> Or is some kind of acceptable variable attenuation possible in each room?
>
> Google turns up L-pads. If I understand, an L-pad keeps 8-ohm impedance on
> the line from the amplifier, while providing an attenuated signal to the
> speaker.
>
> As long as it is properly chosen, are there any cautions I should know
> about
> installing an L-pad for each pair of speakers in a room?
>
> Are L-pads reliable (no noise, etc.)? Brands to recommend? Or avoid?
>
> Other ideas? Speak your peace.
>
> Thanks,
> --
> Please, no "Go Google this" replies. I wouldn't
> ask a question here if I hadn't done that already.
>
> DaveC
> me@privacy.net
> This is an invalid return address
> Please reply in the news group
>
I used the Niles speaker selector and the Niles volume controls. The
selector I chose allows 6 pairs of speakers to be attached. It's kinda
pricy. I think the selector is about $100 and the volume controls are about
$50 each.

I'm using it for sound in 4 rooms and it works very well.
Bill
Anonymous
August 2, 2005 10:18:50 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

In article <0001HW.BF14E559004C84AEF02845B0@news.readfreenews.net>,
DaveC <me@privacy.net> wrote:
> > (1) Separate amp at each location, not totally impractical
> > in these days when you can get a pertty fair 100 wpc amp for
> > under $80 if you look around.

> Sources for small amplifiers? Place in wall? Attic?

My solution was to make them, as if hidden don't have to look pretty.
Plenty of kits on the market. I used a DC controlled pre-amp for volume
etc, as then the controls take up a tiny space and can easily be fitted on
a face plate of the type used for sockets etc, and there are no safety
implications if used in a wet room.

This was some time ago - a remote control might do as well.

But I've got an easy to wire house. Victorian with a cellar and dry lined
walls. A modern solid concrete one would be a different matter. ;-)

--
*To steal ideas from *one* person is plagiarism; from many, research*

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.
Anonymous
August 3, 2005 1:48:33 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

DaveC wrote:

> In a distributed audio system in a residence, how can volume control in each
> room be accomplished.

Seperate amplifiers in each room ( or alternatively so-called 'powered speakers'
with inbuilt amplifiers ) is the only solution that preserves audio quality. I
assume you don't want quality trade-offs which is all that any other approach
can offer.

Graham
Anonymous
August 3, 2005 2:51:10 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

In article <1123017933.670578.310400@g49g2000cwa.googlegroups.com>,
Paul Mathews <optoeng@pioneernet.net> wrote:
> With a careful choice of transformers, you can get excellent fidelity
> with distributed audio.

Transformers capable of handling the 'accepted' audio bandwidth for
driving speakers will be *extremely* costly.

> However, I'd still vote for multiple amplifiers and/or digital
> networking if it were my house.

Yup. Although a digital distribution will simply add to the cost.

--
*Corduroy pillows are making headlines.

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.
August 3, 2005 10:42:53 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Thus spake BoborAnn:

> I did this in my home using NXG Impedance matching volume controls ( part
> number NX-VCM80) which you can get on EBay for under $20 each this device
> allows up to 8 sets of speakers to be connected to a receiver.It has taps
> based on how many you are using which allow too to present a constant
> impedance to the receiver. They have 12 steps of attenuation which is plenty
> for me

Using this method, you still have to connect the constant-impedance volume
control units in series-parallel configuration so as to keep 8 ohms total
impedance across the amplifier's output, yes?
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group
Anonymous
August 3, 2005 6:47:42 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

On Tue, 2 Aug 2005 08:42:06 -0700, DaveC <me@privacy.net> wrote:

>> You can often cludge together a system using 100 volt line transformers on
>> a normal amp, and use the power output taps via a switch to give some
>> control of level. Not ideal, but any form of resistive system will sound
>> worse.
>
>You being in the UK, I presume you mean 240:100v line transformers, yes? In
>the USofA this would be half that: 120:50v transformers, yes?

Nope. He's talking about 100v line systems for audio distribution.
As it's voltage based, not current based, you can set up a wide area
coverage and tap off power at any location. The speakers each need a
matching transformer and typically include a volume control.
Anonymous
August 3, 2005 9:53:41 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

On Tue, 2 Aug 2005 09:17:47 -0700, DaveC <me@privacy.net> wrote:

>Is there a wireless solution to distributing audio throughout a residence to
>8 rooms? Digital?
>
>Something similar to wireless computer networking...
>
>Thanks,

I have some 2.4GHz wireless units that can send/receive video and
stereo audio... MATCO ASK-2008-TR

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:( 480)460-2350 | |
| E-mail Address at Website Fax:( 480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.
Anonymous
August 3, 2005 11:19:58 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"DaveC" <me@privacy.net> wrote in message
news:0001HW.BF14EABB004DC7B6F04075B0@news.readfreenews.net...
> Is there a wireless solution to distributing audio throughout a residence
to
> 8 rooms? Digital?

Yes, there is; you can have a central computer acting as a music server,
with a wireless ethernet network, and network music devices such as the
Squeezebox.

So, in each of the eight rooms you'd have speakers and an amplifier (or
powered speakers) and a Squeezebox. You could also have other devices
connected to the amplifier.

So you could have:

Mode 1: All eight rooms playing the same sound from their Squeezebox, with
the Squeezebox acting in multicast mode. The volume in each room would be
controlled by its own amplifier.

Mode 2: Some of the eight rooms playing the same sound from their
Squeezebox, and others playing diferent sounds from the music server via the
Squeezebox. Selection of music in each room is controlled by the Squeezebox
remote control.

Mode 3: Some of the rooms playings sounds from their Squeezboxes, others
playing sounds from local sources (eg, TV with line-out connections, or
their own computer.)

Now: there's no need to use wireless everywhere; you can use a mix of
wired and wireless connections.

The Squeezebox is one of the more expensive devices at £250 or so each. I
have a Netgear MP101, which now cost about £70, but can't do Multicast.

On the other hand, all these devices can do Internet radio. I've not looked
into it, but I suppose you ought to be able to set up your own Internet
radion statio within your home, so all your Netgear boxes could tune into
it. (Does anyone know how to set up an Intenet radio station for use within
their home?)

Costs for a basic quality system (YMMV):

Central Computer ... whatever
Central Wireless Ethernet hub ... £70

Per room Netgear MP101: £70
Per room amplifier: eg Richer Sounds Cambridge A1 £80
Per room speakers: eg Richer Sounds Celestion F10 £110
Per room leads, stands etc: £40

So I think you could get a basic system with reasonable quality small
speakers at £300 a room; and for an extra £50 you could get better
floorstanding speakers. And of course you can use different-quality
equipment in each room.

Don't forget, this is providing all the audio requirements in each room ...
central music, TV, computer, etc.

Tim


..
Anonymous
August 4, 2005 1:42:26 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

rrobertsims@gmail.com wrote:

> Simple answer. Purchase a speaker selector switch at any electronics
> outlet. The selector switch takes one pair of amplifier outputs and
> spilts out the output to 4 and up to 8 stereo pairs. (it takes care of
> the impedance problems).

Pray - tell us - how does it do that - " it takes care of the impedance
problems " ?

I rather think it does no such thing.

Graham
Anonymous
August 4, 2005 1:42:27 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:42F12C32.F204832B@hotmail.com...
>
> rrobertsims@gmail.com wrote:
>
>> Simple answer. Purchase a speaker selector switch at any electronics
>> outlet. The selector switch takes one pair of amplifier outputs and
>> spilts out the output to 4 and up to 8 stereo pairs. (it takes care of
>> the impedance problems).
>
> Pray - tell us - how does it do that - " it takes care of the impedance
> problems " ?
>
> I rather think it does no such thing.

**Some do. The switch boxes typically either perform an internal
series/parallel thing, and/or place a high power (typically) 2 Ohm resistor
in the path.


--
Trevor Wilson
www.rageaudio.com.au
Anonymous
August 4, 2005 1:45:06 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

DaveC wrote:

> Is there a wireless solution to distributing audio throughout a residence to
> 8 rooms? Digital?
>
> Something similar to wireless computer networking...

Currently only at mp3 like quality. True16 bit linear pcm in stereo @ 44kHz
sampling requires something like about 6 Mbps of bandwidth.

Graham
Anonymous
August 4, 2005 3:25:41 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Trevor Wilson wrote:

> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> news:42F12C32.F204832B@hotmail.com...
> >
> > rrobertsims@gmail.com wrote:
> >
> >> Simple answer. Purchase a speaker selector switch at any electronics
> >> outlet. The selector switch takes one pair of amplifier outputs and
> >> spilts out the output to 4 and up to 8 stereo pairs. (it takes care of
> >> the impedance problems).
> >
> > Pray - tell us - how does it do that - " it takes care of the impedance
> > problems " ?
> >
> > I rather think it does no such thing.
>
> **Some do. The switch boxes typically either perform an internal
> series/parallel thing, and/or place a high power (typically) 2 Ohm resistor
> in the path.

I was vaguely wondering about that. Neither approach is a good idea for
fidelity though.

Graham
Anonymous
August 4, 2005 3:25:42 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:42F14465.693C517@hotmail.com...
>
> Trevor Wilson wrote:
>
>> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
>> news:42F12C32.F204832B@hotmail.com...
>> >
>> > rrobertsims@gmail.com wrote:
>> >
>> >> Simple answer. Purchase a speaker selector switch at any electronics
>> >> outlet. The selector switch takes one pair of amplifier outputs and
>> >> spilts out the output to 4 and up to 8 stereo pairs. (it takes care
>> >> of
>> >> the impedance problems).
>> >
>> > Pray - tell us - how does it do that - " it takes care of the impedance
>> > problems " ?
>> >
>> > I rather think it does no such thing.
>>
>> **Some do. The switch boxes typically either perform an internal
>> series/parallel thing, and/or place a high power (typically) 2 Ohm
>> resistor
>> in the path.
>
> I was vaguely wondering about that. Neither approach is a good idea for
> fidelity though.

**Of course. My first post outlined the best approach.


--
Trevor Wilson
www.rageaudio.com.au
Anonymous
August 4, 2005 4:13:20 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Trevor Wilson wrote:

> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> news:42F14465.693C517@hotmail.com...
> >
> > Trevor Wilson wrote:
> >
> >> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> >> news:42F12C32.F204832B@hotmail.com...
> >> >
> >> > rrobertsims@gmail.com wrote:
> >> >
> >> >> Simple answer. Purchase a speaker selector switch at any electronics
> >> >> outlet. The selector switch takes one pair of amplifier outputs and
> >> >> spilts out the output to 4 and up to 8 stereo pairs. (it takes care
> >> >> of
> >> >> the impedance problems).
> >> >
> >> > Pray - tell us - how does it do that - " it takes care of the impedance
> >> > problems " ?
> >> >
> >> > I rather think it does no such thing.
> >>
> >> **Some do. The switch boxes typically either perform an internal
> >> series/parallel thing, and/or place a high power (typically) 2 Ohm
> >> resistor
> >> in the path.
> >
> > I was vaguely wondering about that. Neither approach is a good idea for
> > fidelity though.
>
> **Of course. My first post outlined the best approach.

Indeed and I agree 100%. At some time in the future decent quality wireless
links will become available using the 2.4GHz band using a method compatible with
IEC 802.11. I'm actually waiting for a certain company to announce its
commercial availability. Last time I checked it was being held up for ETSI
compliance issues.

Graham
Anonymous
August 4, 2005 5:07:23 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

dpierce@cartchunk.org wrote:

> dpie...@cartchunk.org wrote:
> > Pooh Bear wrote:
> > > DaveC wrote:
> > >
> > > > Is there a wireless solution to distributing audio throughout a residence to
> > > > 8 rooms? Digital?
> > > >
> > > > Something similar to wireless computer networking...
> > >
> > > Currently only at mp3 like quality. True16 bit linear pcm in
> > > stereo @ 44kHz sampling requires something like about 6 Mbps
> > > of bandwidth.
> >
> > 44,1000 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>
> Sorry, that's:
>
> 44,1000 samples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>
> or
>
> 44.1 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>
> In any case, it's 1.4 Mbits/sec, NOT 6 Mbits/sec.

That's the raw data rate only !

Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
and redundancy for lost packets - and I've no idea how the data's encapsulated -
there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
it on good authority from some guys who are developing the product. I was quite
surprised how much overhead is required myself actually.

Graham
Anonymous
August 4, 2005 5:07:24 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

On 8/3/05 5:07 PM, in article 42F15C3B.7744897F@hotmail.com, "Pooh Bear"
<rabbitsfriendsandrelations@hotmail.com> wrote:

> dpierce@cartchunk.org wrote:
>
>> dpie...@cartchunk.org wrote:
>>> Pooh Bear wrote:
>>>> DaveC wrote:
>>>>
>>>>> Is there a wireless solution to distributing audio throughout a residence
>>>>> to
>>>>> 8 rooms? Digital?
>>>>>
>>>>> Something similar to wireless computer networking...
>>>>
>>>> Currently only at mp3 like quality. True16 bit linear pcm in
>>>> stereo @ 44kHz sampling requires something like about 6 Mbps
>>>> of bandwidth.
>>>
>>> 44,1000 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>
>> Sorry, that's:
>>
>> 44,1000 samples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>
>> or
>>
>> 44.1 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>
>> In any case, it's 1.4 Mbits/sec, NOT 6 Mbits/sec.
>
> That's the raw data rate only !
>
> Now you have to add overhead for the frequency hopping stuff, handshaking,
> whatever
> and redundancy for lost packets - and I've no idea how the data's encapsulated
> -
> there'll doubtless be extra stuff there too. I'm not calculating this myself,
> I have
> it on good authority from some guys who are developing the product. I was
> quite
> surprised how much overhead is required myself actually.

You've provided other BS swearing about the correctness of it and have been
wrong. Your credibility slipped before this and stating 6 Mbit/s here
confirms you don't know Jack.
Anonymous
August 4, 2005 5:33:48 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

On Thu, 04 Aug 2005 01:07:23 +0100, Pooh Bear wrote:

> dpierce@cartchunk.org wrote:
>
>> dpie...@cartchunk.org wrote:
>> > Pooh Bear wrote:
>> > > DaveC wrote:
>> > >
>> > > > Is there a wireless solution to distributing audio throughout a residence to
>> > > > 8 rooms? Digital?
>> > > >
>> > > > Something similar to wireless computer networking...
>> > >
>> > > Currently only at mp3 like quality. True16 bit linear pcm in
>> > > stereo @ 44kHz sampling requires something like about 6 Mbps
>> > > of bandwidth.
>> >
>> > 44,1000 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>
>> Sorry, that's:
>>
>> 44,1000 samples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>
>> or
>>
>> 44.1 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>
>> In any case, it's 1.4 Mbits/sec, NOT 6 Mbits/sec.
>
> That's the raw data rate only !
>
> Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
> and redundancy for lost packets - and I've no idea how the data's encapsulated -
> there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
> it on good authority from some guys who are developing the product. I was quite
> surprised how much overhead is required myself actually.
>
You don't have to use TCP/IP, and you don't need, or even want, lost
packet redundancy, at least not for streaming audio. If you need a
protocol at all, use something like UUCP.

Cheers!
Rich
August 4, 2005 5:41:17 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Pooh Bear wrote:
> dpierce@cartchunk.org wrote:
>
>> dpie...@cartchunk.org wrote:
>>> Pooh Bear wrote:
>>>> DaveC wrote:
>>>>
>>>>> Is there a wireless solution to distributing audio throughout a residence to
>>>>> 8 rooms? Digital?
>>>>>
>>>>> Something similar to wireless computer networking...
>>>> Currently only at mp3 like quality. True16 bit linear pcm in
>>>> stereo @ 44kHz sampling requires something like about 6 Mbps
>>>> of bandwidth.
>>> 44,1000 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>> Sorry, that's:
>>
>> 44,1000 samples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>
>> or
>>
>> 44.1 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>
>> In any case, it's 1.4 Mbits/sec, NOT 6 Mbits/sec.
>
> That's the raw data rate only !
>
> Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
> and redundancy for lost packets - and I've no idea how the data's encapsulated -
> there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
> it on good authority from some guys who are developing the product. I was quite
> surprised how much overhead is required myself actually.
>
> Graham
>
>
Even accepting your numbers, a 10 Mbps link is adequate. So it's not
necessary to resort to MP3.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form che...@prodigy.net.
August 4, 2005 6:01:51 AM

Archived from groups: rec.audio.tech (More info?)

"Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:42F14F90.1426018A@hotmail.com...

> Indeed and I agree 100%. At some time in the future decent quality
wireless
> links will become available using the 2.4GHz band using a method
compatible with
> IEC 802.11. I'm actually waiting for a certain company to announce its
> commercial availability. Last time I checked it was being held up for ETSI
> compliance issues.
>
> Graham
>

*PLEASE* is it necessary to be crossposting to five groups at once
in this thread. Do we really be needing to download this message
five times ? I restriced my reply to the group I am reading this from.

Why not utilise radio headphones, and then connect the receiver
to a seperate amp in each room, or just *wear them* as you walk
from room to room ?

.............. Zed
Anonymous
August 4, 2005 7:00:51 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Rich Grise wrote:

> On Thu, 04 Aug 2005 01:07:23 +0100, Pooh Bear wrote:
>
> > That's the raw data rate only !
> >
> > Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
> > and redundancy for lost packets - and I've no idea how the data's encapsulated -
> > there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
> > it on good authority from some guys who are developing the product. I was quite
> > surprised how much overhead is required myself actually.
>
> You don't have to use TCP/IP, and you don't need, or even want, lost
> packet redundancy, at least not for streaming audio. If you need a
> protocol at all, use something like UUCP.

If you don't account for lost packets what's going to happen to any lost audio data ? I'll
ask some more next time I talk to the guys about the protocol they're using.

Graham
Anonymous
August 4, 2005 7:05:11 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

CJT wrote:

> Pooh Bear wrote:
> > dpierce@cartchunk.org wrote:
> >
> >> dpie...@cartchunk.org wrote:
> >>> Pooh Bear wrote:
> >>>> DaveC wrote:
> >>>>
> >>>>> Is there a wireless solution to distributing audio throughout a residence to
> >>>>> 8 rooms? Digital?
> >>>>>
> >>>>> Something similar to wireless computer networking...
> >>>> Currently only at mp3 like quality. True16 bit linear pcm in
> >>>> stereo @ 44kHz sampling requires something like about 6 Mbps
> >>>> of bandwidth.
> >>> 44,1000 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
> >> Sorry, that's:
> >>
> >> 44,1000 samples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
> >>
> >> or
> >>
> >> 44.1 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
> >>
> >> In any case, it's 1.4 Mbits/sec, NOT 6 Mbits/sec.
> >
> > That's the raw data rate only !
> >
> > Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
> > and redundancy for lost packets - and I've no idea how the data's encapsulated -
> > there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
> > it on good authority from some guys who are developing the product. I was quite
> > surprised how much overhead is required myself actually.
> >
> > Graham
>
>
> Even accepting your numbers, a 10 Mbps link is adequate. So it's not
> necessary to resort to MP3.

10Mbps would indeed be fine if the link could grab most of the relevant bandwidth.

Existing 2.4G audiolinks are mostly 'mp3' like. Look for the term 'sub band codec' in the
description - although many are simply sold using the confusing and meaningless term
'stereo quality' !

I note that Jim Thompson commented on a analogue FM based 2.4G audio link too.

Graham
August 4, 2005 8:19:32 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Pooh Bear wrote:
> Rich Grise wrote:
>
>> On Thu, 04 Aug 2005 01:07:23 +0100, Pooh Bear wrote:
>>
>>> That's the raw data rate only !
>>>
>>> Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
>>> and redundancy for lost packets - and I've no idea how the data's encapsulated -
>>> there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
>>> it on good authority from some guys who are developing the product. I was quite
>>> surprised how much overhead is required myself actually.
>> You don't have to use TCP/IP, and you don't need, or even want, lost
>> packet redundancy, at least not for streaming audio. If you need a
>> protocol at all, use something like UUCP.
>
> If you don't account for lost packets what's going to happen to any lost audio data ? I'll
> ask some more next time I talk to the guys about the protocol they're using.
>
> Graham
>
Once their time has passed, they're irrelevant.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form che...@prodigy.net.
Anonymous
August 4, 2005 9:09:01 AM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

In article <42F14F90.1426018A@hotmail.com>, Pooh Bear <rabbitsfriendsand
relations@hotmail.com> writes
>
>Trevor Wilson wrote:
>
>> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
>> news:42F14465.693C517@hotmail.com...
>> >
>> > Trevor Wilson wrote:
>> >
>> >> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
>> >> news:42F12C32.F204832B@hotmail.com...
>> >> >
>> >> > rrobertsims@gmail.com wrote:
>> >> >
>> >> >> Simple answer. Purchase a speaker selector switch at any electronics
>> >> >> outlet. The selector switch takes one pair of amplifier outputs and
>> >> >> spilts out the output to 4 and up to 8 stereo pairs. (it takes care
>> >> >> of
>> >> >> the impedance problems).
>> >> >
>> >> > Pray - tell us - how does it do that - " it takes care of the impedance
>> >> > problems " ?
>> >> >
>> >> > I rather think it does no such thing.
>> >>
>> >> **Some do. The switch boxes typically either perform an internal
>> >> series/parallel thing, and/or place a high power (typically) 2 Ohm
>> >> resistor
>> >> in the path.
>> >
>> > I was vaguely wondering about that. Neither approach is a good idea for
>> > fidelity though.
>>
>> **Of course. My first post outlined the best approach.
>
>Indeed and I agree 100%. At some time in the future decent quality wireless
>links will become available using the 2.4GHz band using a method compatible with
>IEC 802.11. I'm actually waiting for a certain company to announce its
>commercial availability. Last time I checked it was being held up for ETSI
>compliance issues.
>
>Graham
>

Www.barix.com

any use?......
--
Tony Sayer
Anonymous
August 4, 2005 12:46:46 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:42F177D7.2CF06A43@hotmail.com...

> Existing 2.4G audiolinks are mostly 'mp3' like. Look for the term 'sub
band codec' in the
> description - although many are simply sold using the confusing and
meaningless term
> 'stereo quality' !

Well, I use a wireless link for my Netgear MP101, and it handles .wav files.

I see it says on the box that the MP101 uses 802.11g, which uses the 2.4GHz
technology, and speeds are "up to 54Mbps" (yea, right ...).

Tim

..
Anonymous
August 4, 2005 5:48:21 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"CJT" <abujlehc@prodigy.net> wrote in message
news:42F1723E.4060406@prodigy.net

>>>
>>> 44.1 ksamples/sec * 16 bits/sample * 2 channels =
>>> 1,411,200 bits/sec

>>> In any case, it's 1.4 Mbits/sec, NOT 6 Mbits/sec.

>> That's the raw data rate only !
>
>> Now you have to add overhead for the frequency hopping
>> stuff, handshaking, whatever and redundancy for lost
>> packets - and I've no idea how the data's encapsulated -
>> there'll doubtless be extra stuff there too. I'm not
>> calculating this myself, I have it on good authority
>> from some guys who are developing the product. I was
>> quite surprised how much overhead is required myself
>> actually.

> Even accepting your numbers, a 10 Mbps link is adequate.
> So it's not necessary to resort to MP3.

I was just listening to some .wav files stored on a file
server across the room, using a SMC 2662W USB-attached
plain-old-vanilla old-tech, low-tech 802.11b wireless
interface. The file I was listening to with Winamp was a
44/16 stereo .wav file.

There's also the slight matter of 802.11a which delivers an
uncompressed 54 mbps, over shorter distances but still
plenty fine to reach across a room or a house.
Anonymous
August 4, 2005 6:05:57 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

CJT wrote:

> Pooh Bear wrote:
> > Rich Grise wrote:
> >
> >> On Thu, 04 Aug 2005 01:07:23 +0100, Pooh Bear wrote:
> >>
> >>> That's the raw data rate only !
> >>>
> >>> Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
> >>> and redundancy for lost packets - and I've no idea how the data's encapsulated -
> >>> there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
> >>> it on good authority from some guys who are developing the product. I was quite
> >>> surprised how much overhead is required myself actually.
> >> You don't have to use TCP/IP, and you don't need, or even want, lost
> >> packet redundancy, at least not for streaming audio. If you need a
> >> protocol at all, use something like UUCP.
> >
> > If you don't account for lost packets what's going to happen to any lost audio data ? I'll
> > ask some more next time I talk to the guys about the protocol they're using.
> >
> > Graham
>
> Once their time has passed, they're irrelevant.
>

Which is why you have a receive buffer and there's latency between transmission and reception.

Graham
Anonymous
August 4, 2005 6:09:41 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Tim Martin wrote:

> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> news:42F177D7.2CF06A43@hotmail.com...
>
> > Existing 2.4G audiolinks are mostly 'mp3' like. Look for the term 'sub
> band codec' in the
> > description - although many are simply sold using the confusing and
> meaningless term
> > 'stereo quality' !
>
> Well, I use a wireless link for my Netgear MP101, and it handles .wav files.
>
> I see it says on the box that the MP101 uses 802.11g, which uses the 2.4GHz
> technology, and speeds are "up to 54Mbps" (yea, right ...).
>

Product Specifications
• Digital Audio File Formats:
- MP3 up to 320 Kbps or variable bit rate (VBR)
- WMA 8/9 to 192 Kbps
- Internet Radio (streaming MP3)

http://www.netgear.com/pdf_docs/MP101_ds_NA_30Nov04.pdf

Trust me - uncompressed digital audio wireless links are not yet available. I
expect the MP101 compresses wav files on the fly.

Graham
Anonymous
August 4, 2005 6:12:18 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Don Bowey wrote:

> On 8/3/05 5:07 PM, in article 42F15C3B.7744897F@hotmail.com, "Pooh Bear"
> <rabbitsfriendsandrelations@hotmail.com> wrote:
>
> > dpierce@cartchunk.org wrote:
> >
> >> dpie...@cartchunk.org wrote:
> >>> Pooh Bear wrote:
> >>>> DaveC wrote:
> >>>>
> >>>>> Is there a wireless solution to distributing audio throughout a residence
> >>>>> to
> >>>>> 8 rooms? Digital?
> >>>>>
> >>>>> Something similar to wireless computer networking...
> >>>>
> >>>> Currently only at mp3 like quality. True16 bit linear pcm in
> >>>> stereo @ 44kHz sampling requires something like about 6 Mbps
> >>>> of bandwidth.
> >>>
> >>> 44,1000 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
> >>
> >> Sorry, that's:
> >>
> >> 44,1000 samples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
> >>
> >> or
> >>
> >> 44.1 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
> >>
> >> In any case, it's 1.4 Mbits/sec, NOT 6 Mbits/sec.
> >
> > That's the raw data rate only !
> >
> > Now you have to add overhead for the frequency hopping stuff, handshaking,
> > whatever
> > and redundancy for lost packets - and I've no idea how the data's encapsulated
> > -
> > there'll doubtless be extra stuff there too. I'm not calculating this myself,
> > I have
> > it on good authority from some guys who are developing the product. I was
> > quite
> > surprised how much overhead is required myself actually.
>
> You've provided other BS swearing about the correctness of it and have been
> wrong. Your credibility slipped before this and stating 6 Mbit/s here
> confirms you don't know Jack.

So, if I was to point you to a company that's actually working on uncompressed
digital audio links and they confirmed what I said, would you apologise for your
stupid comment above ?

It appears that *YOU* are the one who 'knows jack' since you're basically talking
straight out of your arse. I suggest you go learn something about the technology.

Graham
Anonymous
August 4, 2005 6:12:19 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

On 8/4/05 6:12 AM, in article 42F21432.E8D0F801@hotmail.com, "Pooh Bear"
<rabbitsfriendsandrelations@hotmail.com> wrote:

> Don Bowey wrote:
>
>> On 8/3/05 5:07 PM, in article 42F15C3B.7744897F@hotmail.com, "Pooh Bear"
>> <rabbitsfriendsandrelations@hotmail.com> wrote:
>>
>>> dpierce@cartchunk.org wrote:
>>>
>>>> dpie...@cartchunk.org wrote:
>>>>> Pooh Bear wrote:
>>>>>> DaveC wrote:
>>>>>>
>>>>>>> Is there a wireless solution to distributing audio throughout a
>>>>>>> residence
>>>>>>> to
>>>>>>> 8 rooms? Digital?
>>>>>>>
>>>>>>> Something similar to wireless computer networking...
>>>>>>
>>>>>> Currently only at mp3 like quality. True16 bit linear pcm in
>>>>>> stereo @ 44kHz sampling requires something like about 6 Mbps
>>>>>> of bandwidth.
>>>>>
>>>>> 44,1000 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>>>
>>>> Sorry, that's:
>>>>
>>>> 44,1000 samples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>>>
>>>> or
>>>>
>>>> 44.1 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>>>
>>>> In any case, it's 1.4 Mbits/sec, NOT 6 Mbits/sec.
>>>
>>> That's the raw data rate only !
>>>
>>> Now you have to add overhead for the frequency hopping stuff, handshaking,
>>> whatever
>>> and redundancy for lost packets - and I've no idea how the data's
>>> encapsulated
>>> -
>>> there'll doubtless be extra stuff there too. I'm not calculating this
>>> myself,
>>> I have
>>> it on good authority from some guys who are developing the product. I was
>>> quite
>>> surprised how much overhead is required myself actually.
>>
>> You've provided other BS swearing about the correctness of it and have been
>> wrong. Your credibility slipped before this and stating 6 Mbit/s here
>> confirms you don't know Jack.
>
> So, if I was to point you to a company that's actually working on uncompressed
> digital audio links and they confirmed what I said, would you apologise for
> your
> stupid comment above ?
>
> It appears that *YOU* are the one who 'knows jack' since you're basically
> talking
> straight out of your arse. I suggest you go learn something about the
> technology.

I don't care a whole lot about what *one* company is *working on*. How
about you point me to an *ANSI* Standard, or even one in progress in a
Working Group?

Oh..... I remember, you like to make reference to "standards" that aren't
really Standards.

IMHO you aren't trustworthy in discussions.
Anonymous
August 4, 2005 6:14:28 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

tony sayer wrote:

> In article <42F14F90.1426018A@hotmail.com>, Pooh Bear <rabbitsfriendsand
> relations@hotmail.com> writes
> >
> >Trevor Wilson wrote:
> >
> >> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> >> news:42F14465.693C517@hotmail.com...
> >> >
> >> > Trevor Wilson wrote:
> >> >
> >> >> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> >> >> news:42F12C32.F204832B@hotmail.com...
> >> >> >
> >> >> > rrobertsims@gmail.com wrote:
> >> >> >
> >> >> >> Simple answer. Purchase a speaker selector switch at any electronics
> >> >> >> outlet. The selector switch takes one pair of amplifier outputs and
> >> >> >> spilts out the output to 4 and up to 8 stereo pairs. (it takes care
> >> >> >> of
> >> >> >> the impedance problems).
> >> >> >
> >> >> > Pray - tell us - how does it do that - " it takes care of the impedance
> >> >> > problems " ?
> >> >> >
> >> >> > I rather think it does no such thing.
> >> >>
> >> >> **Some do. The switch boxes typically either perform an internal
> >> >> series/parallel thing, and/or place a high power (typically) 2 Ohm
> >> >> resistor
> >> >> in the path.
> >> >
> >> > I was vaguely wondering about that. Neither approach is a good idea for
> >> > fidelity though.
> >>
> >> **Of course. My first post outlined the best approach.
> >
> >Indeed and I agree 100%. At some time in the future decent quality wireless
> >links will become available using the 2.4GHz band using a method compatible with
> >IEC 802.11. I'm actually waiting for a certain company to announce its
> >commercial availability. Last time I checked it was being held up for ETSI
> >compliance issues.
> >
> >Graham
> >
>
> Www.barix.com
>
> any use?......

Last time I looked anythting they had was compressed.

I've been round the loop several times over a year ago and all the consumer stuff is
the same. They talk of 'high quality' or 'stereo quality' but never ever mention
it's not linear pcm.

Graham
Anonymous
August 4, 2005 6:16:04 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

tony sayer wrote:

> In article <42F14F90.1426018A@hotmail.com>, Pooh Bear <rabbitsfriendsand
> relations@hotmail.com> writes
> >
> >Trevor Wilson wrote:
> >
> >> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> >> news:42F14465.693C517@hotmail.com...
> >> >
> >> > Trevor Wilson wrote:
> >> >
> >> >> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> >> >> news:42F12C32.F204832B@hotmail.com...
> >> >> >
> >> >> > rrobertsims@gmail.com wrote:
> >> >> >
> >> >> >> Simple answer. Purchase a speaker selector switch at any electronics
> >> >> >> outlet. The selector switch takes one pair of amplifier outputs and
> >> >> >> spilts out the output to 4 and up to 8 stereo pairs. (it takes care
> >> >> >> of
> >> >> >> the impedance problems).
> >> >> >
> >> >> > Pray - tell us - how does it do that - " it takes care of the impedance
> >> >> > problems " ?
> >> >> >
> >> >> > I rather think it does no such thing.
> >> >>
> >> >> **Some do. The switch boxes typically either perform an internal
> >> >> series/parallel thing, and/or place a high power (typically) 2 Ohm
> >> >> resistor
> >> >> in the path.
> >> >
> >> > I was vaguely wondering about that. Neither approach is a good idea for
> >> > fidelity though.
> >>
> >> **Of course. My first post outlined the best approach.
> >
> >Indeed and I agree 100%. At some time in the future decent quality wireless
> >links will become available using the 2.4GHz band using a method compatible with
> >IEC 802.11. I'm actually waiting for a certain company to announce its
> >commercial availability. Last time I checked it was being held up for ETSI
> >compliance issues.
> >
> >Graham
>
>
> Www.barix.com
>
> any use?......

Nought's changed !

With Barix you can bring your audio into the network. The Barix Instreamer or MP3
encoder is an intelligent streaming component that converts analog and digital audio
into MP3 which it then transmits into the network.

http://www.barix.com/index.php?option=com_content&task=...

Graham
Anonymous
August 4, 2005 7:26:47 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

"Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:42F176D3.675179AF@hotmail.com...
>
> Rich Grise wrote:
>
>> On Thu, 04 Aug 2005 01:07:23 +0100, Pooh Bear wrote:
>>
>> > That's the raw data rate only !
>> >
>> > Now you have to add overhead for the frequency hopping stuff,
>> > handshaking, whatever
>> > and redundancy for lost packets - and I've no idea how the data's
>> > encapsulated -
>> > there'll doubtless be extra stuff there too. I'm not calculating this
>> > myself, I have
>> > it on good authority from some guys who are developing the product. I
>> > was quite
>> > surprised how much overhead is required myself actually.
>>
>> You don't have to use TCP/IP, and you don't need, or even want, lost
>> packet redundancy, at least not for streaming audio. If you need a
>> protocol at all, use something like UUCP.
>
> If you don't account for lost packets what's going to happen to any lost
> audio data ? I'll
> ask some more next time I talk to the guys about the protocol they're
> using.
>
> Graham
>

You get a 'pfsst' noise (that may lose something in translation) until
everything sync's up again. Audio streaming isn't generally critical stuff
so why bother trying to make up the lost stuff.

Ken
Anonymous
August 4, 2005 7:26:48 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Ken Taylor wrote:

> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> news:42F176D3.675179AF@hotmail.com...
>
> > If you don't account for lost packets what's going to happen to any lost
> > audio data ? I'll
> > ask some more next time I talk to the guys about the protocol they're
> > using.
> >
> > Graham
> >
>
> You get a 'pfsst' noise (that may lose something in translation) until
> everything sync's up again. Audio streaming isn't generally critical stuff
> so why bother trying to make up the lost stuff.

That's what I thought.

That makes such a scheme unacceptable for serious hi-fi or professional audio
usage which will be the mainstay of the market for such a product.

Ergo... redundancy *is* required.

Graham
August 4, 2005 7:55:15 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Pooh Bear wrote:
>
> CJT wrote:
>
>> Pooh Bear wrote:
>>> Rich Grise wrote:
>>>
>>>> On Thu, 04 Aug 2005 01:07:23 +0100, Pooh Bear wrote:
>>>>
>>>>> That's the raw data rate only !
>>>>>
>>>>> Now you have to add overhead for the frequency hopping stuff, handshaking, whatever
>>>>> and redundancy for lost packets - and I've no idea how the data's encapsulated -
>>>>> there'll doubtless be extra stuff there too. I'm not calculating this myself, I have
>>>>> it on good authority from some guys who are developing the product. I was quite
>>>>> surprised how much overhead is required myself actually.
>>>> You don't have to use TCP/IP, and you don't need, or even want, lost
>>>> packet redundancy, at least not for streaming audio. If you need a
>>>> protocol at all, use something like UUCP.
>>> If you don't account for lost packets what's going to happen to any lost audio data ? I'll
>>> ask some more next time I talk to the guys about the protocol they're using.
>>>
>>> Graham
>> Once their time has passed, they're irrelevant.
>>
>
> Which is why you have a receive buffer and there's latency between transmission and reception.
>
> Graham
>
Unless you buffer the whole session (e.g. a complete song, or perhaps
even a complete CD), there's always the possibility of a buffer not
arriving in time.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form che...@prodigy.net.
August 4, 2005 7:59:45 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Pooh Bear wrote:
> Don Bowey wrote:
>
>> On 8/3/05 5:07 PM, in article 42F15C3B.7744897F@hotmail.com, "Pooh Bear"
>> <rabbitsfriendsandrelations@hotmail.com> wrote:
>>
>>> dpierce@cartchunk.org wrote:
>>>
>>>> dpie...@cartchunk.org wrote:
>>>>> Pooh Bear wrote:
>>>>>> DaveC wrote:
>>>>>>
>>>>>>> Is there a wireless solution to distributing audio throughout a residence
>>>>>>> to
>>>>>>> 8 rooms? Digital?
>>>>>>>
>>>>>>> Something similar to wireless computer networking...
>>>>>> Currently only at mp3 like quality. True16 bit linear pcm in
>>>>>> stereo @ 44kHz sampling requires something like about 6 Mbps
>>>>>> of bandwidth.
>>>>> 44,1000 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>>> Sorry, that's:
>>>>
>>>> 44,1000 samples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>>>
>>>> or
>>>>
>>>> 44.1 ksamples/sec * 16 bits/sample * 2 channels = 1,411,200 bits/sec
>>>>
>>>> In any case, it's 1.4 Mbits/sec, NOT 6 Mbits/sec.
>>> That's the raw data rate only !
>>>
>>> Now you have to add overhead for the frequency hopping stuff, handshaking,
>>> whatever
>>> and redundancy for lost packets - and I've no idea how the data's encapsulated
>>> -
>>> there'll doubtless be extra stuff there too. I'm not calculating this myself,
>>> I have
>>> it on good authority from some guys who are developing the product. I was
>>> quite
>>> surprised how much overhead is required myself actually.
>> You've provided other BS swearing about the correctness of it and have been
>> wrong. Your credibility slipped before this and stating 6 Mbit/s here
>> confirms you don't know Jack.
>
> So, if I was to point you to a company that's actually working on uncompressed
> digital audio links and they confirmed what I said, would you apologise for your
> stupid comment above ?
>
> It appears that *YOU* are the one who 'knows jack' since you're basically talking
> straight out of your arse. I suggest you go learn something about the technology.
>
> Graham
>
>
The Turtle Beach Audiotron does .wav, and if you wanted to, you could
link to it via wireless.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form che...@prodigy.net.
August 4, 2005 8:03:47 PM

Archived from groups: sci.electronics.design,sci.electronics.repair,alt.engineering.electrical,rec.audio.tech,uk.rec.audio (More info?)

Pooh Bear wrote:
> Tim Martin wrote:
>
>
>>"Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
>>news:42F177D7.2CF06A43@hotmail.com...
>>
>>
>>>Existing 2.4G audiolinks are mostly 'mp3' like. Look for the term 'sub
>>
>>band codec' in the
>>
>>>description - although many are simply sold using the confusing and
>>
>>meaningless term
>>
>>>'stereo quality' !
>>
>>Well, I use a wireless link for my Netgear MP101, and it handles .wav files.
>>
>>I see it says on the box that the MP101 uses 802.11g, which uses the 2.4GHz
>>technology, and speeds are "up to 54Mbps" (yea, right ...).
>>
>
>
> Product Specifications
> • Digital Audio File Formats:
> - MP3 up to 320 Kbps or variable bit rate (VBR)
> - WMA 8/9 to 192 Kbps
> - Internet Radio (streaming MP3)
>
> http://www.netgear.com/pdf_docs/MP101_ds_NA_30Nov04.pdf
>
> Trust me - uncompressed digital audio wireless links are not yet available. I
> expect the MP101 compresses wav files on the fly.
>
> Graham
>

Mmm - definitely don't follow you here. My (any) 'g' wireless link has a
real world 2 megabyte per second transfer speed. There is simply no need
for audio compression, and I can see no sign of it happening on either
of the machines in the network. The same with video I'd guess - an
uncompressed avi file will stream in it's native format.

The Netgear is essentially a mini puter capped by its ability to process
compressed audio. It could happily stream uncompressed audio, subject
only to bandwidth.

Rob
!