question for EE's on rec.

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

question for EE's on rec.

Group: rec.audio.pro Date: Sat, Nov 20, 2004, 6:49pm (EST-3) From:
genericaudioperson@hotmail.com (xy)
hello everyone.
i'm looking into having my video monitor go wireless. will this
interfere with sensitive condenser microphone recordings?
my basic instincts say to avoid it since it would put some sort of RF
into the air. but someone who actually knows something about electronics
would be able to say if it's in a different frequency band.
right now i have my kvm on an rj-45 remote setup, but I'd like to go
wireless so i can take the stuff back and forth into an iso booth
easily.
will the real EE's please stand up, please stand up, please stand up.
<<<<<<<<<<<<<<<

Lots of variables. Depends on the transmitter output, distance from the
mic, some mics are more susceptable than others. Why not try it and see
what works for you.

Eric

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

<standing up>

While a neophyte at the rap game, I can tell you that you may run into
some problems depending on the technology used. It has to do with
these new 802.11g wireless "double the speed" base stations (the ones
with two antennas). While the normal single channel devices will
present no lower frequency noise, the two antennas together at slightly
diferent requencies might creat some noise that you could pick up.
This is similar to a beat frequency in the audio spectrum.

Hope this helps,

Girmann

On 2004-11-20 21:49:23 -0500, genericaudioperson@hotmail.com (xy) said:

> hello everyone.
>
> i'm looking into having my video monitor go wireless. will this
> interfere with sensitive condenser microphone recordings?
>
> my basic instincts say to avoid it since it would put some sort of RF
> into the air. but someone who actually knows something about
> electronics would be able to say if it's in a different frequency
> band.
>
> right now i have my kvm on an rj-45 remote setup, but I'd like to go
> wireless so i can take the stuff back and forth into an iso booth
> easily.
>
> will the real EE's please stand up, please stand up, please stand up.

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

William Sommerwerck <williams@nwlink.com> wrote:
>>> I'm looking into having my video monitor go wireless. Will this
>>> interfere with sensitive condenser microphone recordings?
>
>>> My basic instincts say to avoid it since it would put some sort
>>> of RF into the air. But someone who actually knows something
>>> about electronics would be able to say if it's in a different
>>> frequency band.
>
>There's always "some sort of RF into the air" -- radio and TV stations, computer
>equipment, etc. Whether it interferes with a particular piece of equipment
>depends on the susceptibility of that equipment.
>
>The odds are pretty good that 802.11g equipment will have no effect on your
>mics, or anything else.

Just a second... since when have "wireless video monitors" used 802.11g?
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

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

William Sommerwerck <williams@nwlink.com> wrote:
>>> There's always "some sort of RF into the air" -- radio and TV stations,
>computer
>>> equipment, etc. Whether it interferes with a particular piece of equipment
>>> depends on the susceptibility of that equipment.
>
>>> The odds are pretty good that 802.11g equipment will have no effect on your
>>> mics, or anything else.
>
>> Just a second... since when have "wireless video monitors" used 802.11g?
>
>Agreed, but that's what he said he was using. I don't believe 802.11g (which is
>actually a unit that can handle all the 802.11 frequencies and formats) has
>sufficient bandwidth.

It's also specifically a packet-switching format, not something that can
be easily adapted for wideband video.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

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

In article <6c38b64b.0411261313.5b382b2d@posting.google.com>,
xy <genericaudioperson@hotmail.com> wrote:
>It would typically be with a Neumann TLM-103 and Neumann KM-84 into an
>HV-3 preamp.
>
>This is good quality stuff, so I'm hoping the geniuses who build that
>stuff would have figured out some good rf-rejection ideas to put into
>this equipment.
>
>Any thoughts based on these specifics?

Neumann has a different grounding system than most people use. The
chassis is not bonded to pin 1. You can either add a jumper to your
mike cable to bond the plug shield to pin 1 (and mark the cable), or
you can use special 3-conductor mike cables with the shield tied to
the chassis and split apart from pin 1.

This gives MUCH better RF rejection than conventional methods, BUT it
requires you to use the proper cabling.

Neumann has a white paper on this, I think.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

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

William, not ^entirely^ true.

802.11g can handle 802.11g and 802.11b only. It cannot handle the
802.11a formats or frequencies. If you were to saturate the 54mb/s
stream, you could get 800x600 video at 14fps and 8 bit color without
compression. Of course, the entire channel isn't usable but there's
plenty of bandwidth there. Heck, just doing a back of the hand
calculation shows that a 9.6GB DVD (like the ones you get at the video
store) hold 2 hours of video (compressed) translates into 1.3MB/s or
10.6Mb/s. That is roughly 1/5 of an 802.11g stream - plenty of
headroom.

--Girmann

On 2004-11-26 08:38:13 -0500, "William Sommerwerck" <williams@nwlink.com> said:

>>> There's always "some sort of RF into the air" -- radio and TV stations,
> computer
>>> equipment, etc. Whether it interferes with a particular piece of equipment
>>> depends on the susceptibility of that equipment.
>
>>> The odds are pretty good that 802.11g equipment will have no effect on your
>>> mics, or anything else.
>
>> Just a second... since when have "wireless video monitors" used 802.11g?
>
> Agreed, but that's what he said he was using. I don't believe 802.11g (which is
> actually a unit that can handle all the 802.11 frequencies and formats) has
> sufficient bandwidth.

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

girmann wrote:

> <standing up>
>
> While a neophyte at the rap game, I can tell you that you may run into
> some problems depending on the technology used. It has to do with
> these new 802.11g wireless "double the speed" base stations (the ones
> with two antennas). While the normal single channel devices will
> present no lower frequency noise, the two antennas together at slightly
> diferent requencies might creat some noise that you could pick up.
> This is similar to a beat frequency in the audio spectrum.

No it isn't actually.


Graham

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

I started buying Mogami cables ever since they came out with their
"off the shelf" line at Guitar Center (yay!!!).

I would be real hesitant to chop up a Mogami and re-orient the pins.
Maybe Mogami makes a cable like you say?

Or Maybe the HV-3 could be config'd by the factory to achieve the same
effect?

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

xy <genericaudioperson@hotmail.com> wrote:
>I started buying Mogami cables ever since they came out with their
>"off the shelf" line at Guitar Center (yay!!!).
>
>I would be real hesitant to chop up a Mogami and re-orient the pins.

No re-orientation needed. No chopping. Just add a jumper. The reason
you BUY good cables with proper connectors is to that they can be modified
and repaired as-needed.

>Maybe Mogami makes a cable like you say?

Markertek will definitely make you one for about the same price as a cable
off the shelf. Or you can buy one from Neumann for a huge amount of money.

>Or Maybe the HV-3 could be config'd by the factory to achieve the same
>effect?

No. The issue is that the microphone case is not connected to anything
inside the cable other than the outer shield. There's no way to get that
connection inside the HV-3.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

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

xy <genericaudioperson@hotmail.com> wrote:
>the rj-45 box i'm using now is somewhat surprisingly not ethernet.
>it's a belkin box that converts your kvm into a cat-5 signal via a
>translator box, then reconverts it on the other end via another
>translator box.

Okay. This is probably an impedance conversion gadget, mostly.

>it works fine, but my next step is to go wireless so i can track
>myself in my iso booth and then bring the stuff back out for mixing.
>
>i'm hoping there will be a wireless keyboard/mouse powerful enough to
>go through all that. then it's just a matter of rigging up the
>wireless monitor.

This is non-trivial.

>they make integrated wireless kvm's, but they seem to cost about
>$500-1000.

I have never seen such a thing. I have seen KVM switches with wireless
remote controls, but nothing that allowed you to remote a monitor.
Certainly not at full VGA bandwidth.

>another idea is to simply put a second monitor, mouse and keyboard in
>the iso booth, and simply switch the cat-5 cable whenever i need to go
>into the iso booth.

That would seem the easy way of doing things.

>one cool tip that you guys probably already know (because i'm the
>relative beginner here), is that LCD monitors don't emit rfi, so they
>are good to have in recording situations compared to bulky CRT
>monitors.

Just wait. They don't emit anywhere near as much RFI as a CRT, but they
sure do emit RFI and you'll find the switching supply for the backlight
can be a real pain as a noise source.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

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

In article <cob9sf$4ee$1@panix1.panix.com> kludge@panix.com writes:

> I have never seen such a thing. I have seen KVM switches with wireless
> remote controls, but nothing that allowed you to remote a monitor.
> Certainly not at full VGA bandwidth.

Low power TV transmitter, perhaps? <g>

--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo

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

i could be misinterpreting, but:

http://www.kvm-switches-online.com/lv3500w-am.html



looks cool if you ask me!

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

Scott Dorsey wrote:

> In article <znr1101649416k@trad>, Mike Rivers <mrivers@d-and-d.com> wrote:
> >
> >In article <cob9sf$4ee$1@panix1.panix.com> kludge@panix.com writes:
> >
> >> I have never seen such a thing. I have seen KVM switches with wireless
> >> remote controls, but nothing that allowed you to remote a monitor.
> >> Certainly not at full VGA bandwidth.
> >
> >Low power TV transmitter, perhaps? <g>
>
> Not at full VGA bandwidth. The cheap X-10 television remotes are pretty
> solid out to 6 MHz, which is wide enough to carry S-PDIF audio when you
> need a wideband audio link in a pinch. But it won't even come close to
> VGA.

My lovely Sony 21" trinitron monitor :-) has something like 200MHz video
bandwidth. It's a beauty. Nothing beats a great screen. Pure flat too. I
actually put a straight edge on it to check. Took a bit of getting used to
though. It looks funny to begin with when you're used to convex screens.

I still prefer it on 1280x1024. The letters get too small to read at
1600x1200.


Graham

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

Pooh Bear <rabbitsfriendsandrelations@hotmail.com> wrote in message news:<41A7F173.629AB4E1@hotmail.com>...
> xy wrote:
>
> > It would typically be with a Neumann TLM-103 and Neumann KM-84 into an
> > HV-3 preamp.
> >
> > This is good quality stuff, so I'm hoping the geniuses who build that
> > stuff would have figured out some good rf-rejection ideas to put into
> > this equipment.
> >
> > Any thoughts based on these specifics?
>
> Yup.
>
> 2.4 GHz is just 'way outa sight' for AF devices.
>
> I doubt any audio frequency circuit would respond even if you shoved it up
> the input XLR.
>
> I'm not being facetious btw.
>
>
> Graham

27 MHz CB radio is way above audio frequencies as well, but but it
still gets into some audio installations. If it (RF of some
frequency) can get past the shielding and find a non-linear element
(like a PN junction, or an imperfect solder joint) then it can be
"detected" and whatever audio frequency signal or noise for which it
is serving (intentionally or otherwise) as a carrier can wind up in
the audio.
Of course what's shielding at one frequency may or may not be
shielding at some other frequency. This may work to your advantage or
it may not.

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

unitron wrote:

> Pooh Bear <rabbitsfriendsandrelations@hotmail.com> wrote in message news:<41A7F173.629AB4E1@hotmail.com>...
> > xy wrote:
> >
> > > It would typically be with a Neumann TLM-103 and Neumann KM-84 into an
> > > HV-3 preamp.
> > >
> > > This is good quality stuff, so I'm hoping the geniuses who build that
> > > stuff would have figured out some good rf-rejection ideas to put into
> > > this equipment.
> > >
> > > Any thoughts based on these specifics?
> >
> > Yup.
> >
> > 2.4 GHz is just 'way outa sight' for AF devices.
> >
> > I doubt any audio frequency circuit would respond even if you shoved it up
> > the input XLR.
> >
> > I'm not being facetious btw.
> >
> >
> > Graham
>
> 27 MHz CB radio is way above audio frequencies as well, but but it
> still gets into some audio installations. If it (RF of some
> frequency) can get past the shielding and find a non-linear element
> (like a PN junction, or an imperfect solder joint) then it can be
> "detected" and whatever audio frequency signal or noise for which it
> is serving (intentionally or otherwise) as a carrier can wind up in
> the audio.
> Of course what's shielding at one frequency may or may not be
> shielding at some other frequency. This may work to your advantage or
> it may not.

That's why I didn't say 27MHz would be ok.

CB radios also push out more transmit power that 802.11 too.


Graham

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

"Blind Joni" <blindjoni@aol.com> wrote in message
news:20041130114830.21510.00001372@mb-m11.aol.com
>>> I still prefer it on 1280x1024. The letters get too small to read at
>>> 1600x1200.
>>
>> When you get older, you'll like 1024x768 even better. <g>
>>
>
> I know I do....

Now that the prices of large LCDs are coming down, just get a bigger
monitor. A 19" LCD can make 1280 x 1024 pretty usable, even for the reading
glasses and bifocals crowd.

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

>Now that the prices of large LCDs are coming down, just get a bigger
>monitor. A 19" LCD can make 1280 x 1024 pretty usable, even for the reading
>glasses and bifocals crowd.
>

I'm getting a 43" LCD month..I need to mix from the center of the room and
still see.


John A. Chiara
SOS Recording Studio
Live Sound Inc.
Albany, NY
www.sosrecording.net
518-449-1637

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

>Are you bragging or complaining? ;-)
>

A little of both..missed a killer deal on Black Friday so now I am shopping
again.


John A. Chiara
SOS Recording Studio
Live Sound Inc.
Albany, NY
www.sosrecording.net
518-449-1637

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

In article <c0npq01nvh7bdg725siotqris40vhaeej8@4ax.com> ben_nospam_bradley@mindspring.com writes:

> As a late-forty-something, I've discovered the real secret with
> using higher resolution (without wearing glasses) is to use larger
> size fonts.

That works on things where you have full control over the layout, but
when I try to tell Netscape to not use a font smaller than I can read
easily many web pages come up with text overlaying the graphics. And a
lot of web pages use graphics as text so telling the browser to use a
large font doesn't work.

It's those inconsiderate people who make beautiful web pages!

--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo

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In article <w_mdnXa4782OODHcRVn-vw@comcast.com> arnyk@hotpop.com writes:

> Now that the prices of large LCDs are coming down, just get a bigger
> monitor. A 19" LCD can make 1280 x 1024 pretty usable, even for the reading
> glasses and bifocals crowd.

But then I'd need a bigger desk.

--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo

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Bob Cain <arcane@arcanemethods.com> wrote in
news:cojhn402n38@enews2.newsguy.com:

> How would you, or anyone, characterize the difference
> between LCD and TFT in pretty constant use. I've a 1024x768
> 15" TFT that I love and am looking at a good deal on a 17"
> LCD, a size that I think I could handle at 1280x1024 (at
> least for a couple more years) but I'm not sure I'd be as
> happy with LCD as I am with the active TFT technology.

I haven't gone searching the specialty markets, but none of the generic
computer retailers near me sell reasonable sized thin monitors with more
than 1024x768 resolution until you get to the ridiculously high priced or
oversized models.

Even 18 and 20 inch (equivalent to 19 & 21 inch CRTs) are 1024x768.

My laptop is a 15" with 1400 x 1024. I can't find anything that good in
the popular consumer market.