mic gain and mixers

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

there is this issue that has been bothering me for a while... im soon
going to consider a Mixer/soundcard combo (or something like the
FW1884)

I have alwaz had the problem of getting enough levels using 58's, and
other dynamics (on voice) into the DAW. Be it on the Mackies or on the
Tascams. With the tascams it seems especially bad, even with the
behringer B2 pro, which is a condenser. the Behringer UB seems a lot
easier to work with.

anything i need to know ?

One can get a good level using the DM24 by twewaking the fag end of
the trim pot very carefully (where there is a sudden boost of level)
.... but then a slightly louder pasage and the DM24 pre's clip...

thanks

Sidhu

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

"Sidhu" <thedevil@india.com> wrote in message
> One can get a good level using the DM24 by twewaking the fag end of
> the trim pot very carefully (where there is a sudden boost of level)
> ... but then a slightly louder pasage and the DM24 pre's clip...

I just got a DM24 for live use and have found the same thing. For a
Sennheiser e835, the trip pot was almost all the way up.

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

In article <dc54e171.0408250058.3bef50f5@posting.google.com> thedevil@india.com writes:

> > I just got a DM24 for live use and have found the same thing. For a
> > Sennheiser e835, the trip pot was almost all the way up.
>
>
> so its the same issue with other dynamics also... im sure a lot of
> ppl. will have experience with tascam consoles.. what do u say ? Not
> to forget that it gets a bit difficult with the Mackies too...

Well, what comes out of the mic (and into the console) is very much a
function of what goes into the mic. The same mic used on a snare drum,
a lounge singer, and a mountain dulcimer will require very different
gain settings for the same nominal record level. That's why consoles
have trim (gain) controls. A microphone input needs to be able to work
effectively over a potential dynamic range of greater than 50 dB, and
that's a tough job.

One issue with the TASCAM DM24 (I hope I'm thinking of the right
product here) is that on early production units, the pots used for the
gain trims gave a large gain increase in the last few degrees of
rotation. They corrected this on later models and will update an older
one with new pots, but it isn't a free update. I think it's $400 or
so.


--
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?)

> Well, what comes out of the mic (and into the console) is very much a
> function of what goes into the mic. The same mic used on a snare drum,
> a lounge singer, and a mountain dulcimer will require very different
> gain settings for the same nominal record level.

Very true.. it just seems a lot weaker with the Tascam consoles...
Even with realtively loud soundsource and stuff like condensors on
voice, one need to really tweak the trim control all the way... Same
voice with same mic on a behringer UB is a lot better...


> A microphone input needs to be able to work
> effectively over a potential dynamic range of greater than 50 dB, and
> that's a tough job.

I agree... but is it possible that the Tascams just dont do the job
well enough ?


> One issue with the TASCAM DM24 (I hope I'm thinking of the right
> product here) is that on early production units, the pots used for the
> gain trims gave a large gain increase in the last few degrees of
> rotation. They corrected this on later models and will update an older
> one with new pots, but it isn't a free update. I think it's $400 or
> so.

I am aware of that. All it does it even out the gain pot to be more
linear. And besides it isnt an option we enjoy this side of the world
(India)

I just want to know if other ppl. working on other consoles with mics
like the 58 find it easy (or not so difficult) to get decent levels
out of sources like voice ?

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

Sidhu <thedevil@india.com> wrote:
>> Well, what comes out of the mic (and into the console) is very much a
>> function of what goes into the mic. The same mic used on a snare drum,
>> a lounge singer, and a mountain dulcimer will require very different
>> gain settings for the same nominal record level.
>
>Very true.. it just seems a lot weaker with the Tascam consoles...
>Even with realtively loud soundsource and stuff like condensors on
>voice, one need to really tweak the trim control all the way... Same
>voice with same mic on a behringer UB is a lot better...

Sure, but how does it sound? If the console sounds fine with the trim control
all the way up, don't worry about it. If the console gets noisy with the
trim control at the point where it's needed, that's fine. Don't worry about
the position of the knob, just worry that it's up to the point where you have
enough gain, and it sounds good.

>
>> A microphone input needs to be able to work
>> effectively over a potential dynamic range of greater than 50 dB, and
>> that's a tough job.
>
>I agree... but is it possible that the Tascams just dont do the job
>well enough ?

No, they just probably have lower preamp gain. That's fine, as long as
you don't run out. There's nothing wrong with having the trim control
all the way up... your problems start when you have it all the way up
and still don't have enough gain. But as long as there is enough gain,
don't worry.

>> One issue with the TASCAM DM24 (I hope I'm thinking of the right
>> product here) is that on early production units, the pots used for the
>> gain trims gave a large gain increase in the last few degrees of
>> rotation. They corrected this on later models and will update an older
>> one with new pots, but it isn't a free update. I think it's $400 or
>> so.
>
>I am aware of that. All it does it even out the gain pot to be more
>linear. And besides it isnt an option we enjoy this side of the world
>(India)
>
>I just want to know if other ppl. working on other consoles with mics
>like the 58 find it easy (or not so difficult) to get decent levels
>out of sources like voice ?

The 58 has plenty of output. The problem with it is that the top end is
very muffled, so you might feel the need to boost a lot higher than you
really should, in order to get good intelligibility.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

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

<< Another thing to check is phantom power. Dynamic mics will not need
it, but if the 58 is a Beta 58, then it is a phantom powered dynamic
mic.>>

No, a Beta58 is simply dynamic, no phantom required.

<< Sometimes standalone mic pre's or smaller consoles do not supply
enough P48 juice. >>

And some don't provide 48 volts.




Scott Fraser

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

EricK <eric@Raw-Tracks.com> wrote in message news:<412DDAB3.2050606@Raw-Tracks.com>...
> Sidhu wrote:
>
> > I am aware of that. All it does it even out the gain pot to be more
> > linear. And besides it isnt an option we enjoy this side of the world
> > (India)
>
> The Tascam update for the DM24 pre's actually makes them LESS linear,
> more logarithmic.

My BAd !It all gets soo confusing...

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

Sidhu wrote:

> > Well, what comes out of the mic (and into the console) is very much a
> > function of what goes into the mic. The same mic used on a snare drum,
> > a lounge singer, and a mountain dulcimer will require very different
> > gain settings for the same nominal record level.
>
> Very true.. it just seems a lot weaker with the Tascam consoles...
> Even with realtively loud soundsource and stuff like condensors on
> voice, one need to really tweak the trim control all the way... Same
> voice with same mic on a behringer UB is a lot better...

Behringer's mic pres are likely to be rather more competent.


> > A microphone input needs to be able to work
> > effectively over a potential dynamic range of greater than 50 dB, and
> > that's a tough job.
>
> I agree... but is it possible that the Tascams just dont do the job
> well enough ?

Tascam is hardly known for its excellence in mixing consoles.

I think you located the problem.


> > One issue with the TASCAM DM24 (I hope I'm thinking of the right
> > product here) is that on early production units, the pots used for the
> > gain trims gave a large gain increase in the last few degrees of
> > rotation. They corrected this on later models and will update an older
> > one with new pots, but it isn't a free update. I think it's $400 or
> > so.
>
> I am aware of that. All it does it even out the gain pot to be more
> linear. And besides it isnt an option we enjoy this side of the world
> (India)

Actually the gain pot isn't linear at all nor should it be. In most mic amp
circuits it has to have a ( reverse actually ) log taper to give a log ( dB
) type control law.

The issue is finding the *best* reverse log taper to give a good control
'feel'. 'Standard' pots rarely fit the bill. You need to get a custom law
part made.


> I just want to know if other ppl. working on other consoles with mics
> like the 58 find it easy (or not so difficult) to get decent levels
> out of sources like voice ?

Only if the voice is quiet.

SM58s are hardly the best mics for voice recording btw. Durable for rock and
roll stage use but that's about it.


Graham

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

Scott Dorsey wrote:

> The 58 has plenty of output. The problem with it is that the top end is
> very muffled, so you might feel the need to boost a lot higher than you
> really should, in order to get good intelligibility.

Which in turn makes the signal sound hissier !


Graham

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

Pooh Bear <rabbitsfriendsandrelations@hotmail.com> wrote in message news:<412E7603.BB1DDBCD@hotmail.com>...
> Sidhu wrote:
>
> > > Well, what comes out of the mic (and into the console) is very much a
> > > function of what goes into the mic. The same mic used on a snare drum,
> > > a lounge singer, and a mountain dulcimer will require very different
> > > gain settings for the same nominal record level.
> >
> > Very true.. it just seems a lot weaker with the Tascam consoles...
> > Even with realtively loud soundsource and stuff like condensors on
> > voice, one need to really tweak the trim control all the way... Same
> > voice with same mic on a behringer UB is a lot better...
>
> Behringer's mic pres are likely to be rather more competent.

I.. errr... is there sarcasm out there.. ? my ears, nor the rooms I
work in, nor the gear i use, would allow for a comparison (not that
ive ever had the oppertunity to AB them) But are u saying that the
Behringer UB series mic pres might actually be better... that would be
cool.



> > > A microphone input needs to be able to work
> > > effectively over a potential dynamic range of greater than 50 dB, and
> > > that's a tough job.
> >
> > I agree... but is it possible that the Tascams just dont do the job
> > well enough ?
>
> Tascam is hardly known for its excellence in mixing consoles.
>
> I think you located the problem.

may be. but had a hard time with the mackies too. 32*8 and the D8b.
But not this bad

one problem i have foudn in all consoles so far is the sudden jump of
levels toward the last few degrees of turn.


> > > One issue with the TASCAM DM24 (I hope I'm thinking of the right
> > > product here) is that on early production units, the pots used for the
> > > gain trims gave a large gain increase in the last few degrees of
> > > rotation. They corrected this on later models and will update an older
> > > one with new pots, but it isn't a free update. I think it's $400 or
> > > so.
> >
> > I am aware of that. All it does it even out the gain pot to be more
> > linear. And besides it isnt an option we enjoy this side of the world
> > (India)
>
> Actually the gain pot isn't linear at all nor should it be. In most mic amp
> circuits it has to have a ( reverse actually ) log taper to give a log ( dB
> ) type control law.
>
> The issue is finding the *best* reverse log taper to give a good control
> 'feel'. 'Standard' pots rarely fit the bill. You need to get a custom law
> part made.
>
>
> > I just want to know if other ppl. working on other consoles with mics
> > like the 58 find it easy (or not so difficult) to get decent levels
> > out of sources like voice ?
>
> Only if the voice is quiet.
>
> SM58s are hardly the best mics for voice recording btw. Durable for rock and
> roll stage use but that's about it.


Agreed. But they work rather well if ure doing Radio Drama, where
quality is not
an issue.

Bout the problem of running out of gain. what happens if that i run
out of headroom. To get decent levels with spoken word of average
amplitude (not soft) i need to crank the trim pot all the way (very
carefully towards the end, with just that much to go) A degree less
will result in a drop of level that is huge.
but then if the actor was to suddenly speak loud, the mix pres clip.
(i read that the DM 24 had a lotta headroom, well suited for rok
music)

How many ppl. here have actually worked with tascam consoles ?

thanks
Sidhu

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

Sidhu wrote:

> Pooh Bear <rabbitsfriendsandrelations@hotmail.com> wrote in message news:<412E7603.BB1DDBCD@hotmail.com>...
>
> > Behringer's mic pres are likely to be rather more competent.
>
> I.. errr... is there sarcasm out there.. ?

No actually.

> my ears, nor the rooms I
> work in, nor the gear i use, would allow for a comparison (not that
> ive ever had the oppertunity to AB them) But are u saying that the
> Behringer UB series mic pres might actually be better... that would be
> cool.

I'm sure they will be, although it appears that getting enough gain is
your major problem.



> > Tascam is hardly known for its excellence in mixing consoles.
> >
> > I think you located the problem.
>
> may be. but had a hard time with the mackies too. 32*8 and the D8b.
> But not this bad
>
> one problem i have foudn in all consoles so far is the sudden jump of
> levels toward the last few degrees of turn.

This is often the case.

As I mentioned, the 'taper' - resistance versus rotation of the pot
makes a great difference here. All my
current designs use 'special' tapers that are made to order. There's
nothing stopping anyone else doing this.

Even so, the last 30 degrees or so of pot rotation usually correspond to
a large part of the gain range. This
can be fixed only by a 'super special' taper pot !




> > SM58s are hardly the best mics for voice recording btw. Durable for rock and
> > roll stage use but that's about it.
>
> Agreed. But they work rather well if ure doing Radio Drama, where
> quality is not an issue.

It's isn't an issue ? Why not ? you mean poor quality is OK ?


> Bout the problem of running out of gain. what happens if that i run
> out of headroom. To get decent levels with spoken word of average
> amplitude (not soft) i need to crank the trim pot all the way (very
> carefully towards the end, with just that much to go) A degree less
> will result in a drop of level that is huge.

Those mic trims really sound very 'touchy'.

Also the 'gain structure' of the Tascam may not allow for as much
headroom as some other designs.


> but then if the actor was to suddenly speak loud, the mix pres clip.
> (i read that the DM 24 had a lotta headroom, well suited for rok
> music)
>
> How many ppl. here have actually worked with tascam consoles ?

I haven't. I doubt that you'll find that many. Tascam is really a bottom
end - consumer rather than
semi-professional product IMHO. You appear to be experiencing many
limitations relating to this brand.


Graham

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

> > my ears, nor the rooms I
> > work in, nor the gear i use, would allow for a comparison (not that
> > ive ever had the oppertunity to AB them) But are u saying that the
> > Behringer UB series mic pres might actually be better... that would be
> > cool.
>
> I'm sure they will be, although it appears that getting enough gain is
> your major problem.



Gain is the main issue. Yes. but now that u mention, i have alwaz
liked what came out of my Beheringer more than what is off the Tascam.
just that at a subconsious level i felt that tascam was obviously
better than behringer.




> > may be. but had a hard time with the mackies too. 32*8 and the D8b.
> > But not this bad
> >
> > one problem i have foudn in all consoles so far is the sudden jump of
> > levels toward the last few degrees of turn.
>
> This is often the case.
>
> As I mentioned, the 'taper' - resistance versus rotation of the pot
> makes a great difference here. All my
> current designs use 'special' tapers that are made to order. There's
> nothing stopping anyone else doing this.


U design Consoles ??!!!! (sorry for any ignorance)






> > > SM58s are hardly the best mics for voice recording btw. Durable for rock and
> > > roll stage use but that's about it.
> >
> > Agreed. But they work rather well if ure doing Radio Drama, where
> > quality is not an issue.
>
> It's isn't an issue ? Why not ? you mean poor quality is OK ?



This no way means that what i record is poor. The end product sounds
very decent. What i mean that there is a lot less problems of pops and
spills, so the actors can do what they mostly want withought me having
to interfere very often.
Of course, its not the best of their voices being captured.

Also when i joined this studio (recently) all they had to work with
was 58's, so i stuk, and with a tascam, it's lead me to most of my
miseries. but in retrospect i agree that condensoers are not optimized
for such situations, though im sure they cudve gotten better dynamics
( such as..? ), but they dont like to spend money, and the 58 is
standard.





> > Bout the problem of running out of gain. what happens if that i run
> > out of headroom. To get decent levels with spoken word of average
> > amplitude (not soft) i need to crank the trim pot all the way (very
> > carefully towards the end, with just that much to go) A degree less
> > will result in a drop of level that is huge.
>
> Those mic trims really sound very 'touchy'.


very bad touchy!


>
> Also the 'gain structure' of the Tascam may not allow for as much
> headroom as some other designs.



I think that it's also possible that the huge jump in gain towards one
of the last degrees, and an absolute drop before that, leavs me in a
position where i either track louder than neccesary (hence leaving me
withought much headroom) or too soft.... i wouldve all along prefered
something in between.




> > but then if the actor was to suddenly speak loud, the mix pres clip.
> > (i read that the DM 24 had a lotta headroom, well suited for rok
> > music)
> >
> > How many ppl. here have actually worked with tascam consoles ?
>
> I haven't. I doubt that you'll find that many. Tascam is really a bottom
> end - consumer rather than
> semi-professional product IMHO. You appear to be experiencing many
> limitations relating to this brand.



i am surprised. especially since they get good reviews in most
places.. for example, the ones on soundonsound. And the FW1884 has got
nothing but praise.





Thank you so much for helping me out on this one...

Sidhu

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

"Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:41309180.11A4929A@hotmail.com...
> As I mentioned, the 'taper' - resistance versus rotation of the pot
> makes a great difference here. All my
> current designs use 'special' tapers that are made to order. There's
> nothing stopping anyone else doing this.
>
> Even so, the last 30 degrees or so of pot rotation usually correspond to
> a large part of the gain range. This
> can be fixed only by a 'super special' taper pot !

If you want a *linear* gain increase wrt pot rotation, you don't need a
special taper at all.

TonyP.

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

Paul Stamler wrote:

> "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> news:41309180.11A4929A@hotmail.com...
>
> > > How many ppl. here have actually worked with tascam consoles ?
> >
> > I haven't. I doubt that you'll find that many. Tascam is really a bottom
> > end - consumer rather than
> > semi-professional product IMHO. You appear to be experiencing many
> > limitations relating to this brand.
>
> Which is ironic, since in some ways Tascam *invented* the world of semi-pro
> recording, way back in the early 1970s.

Just shows how 'semi-pro' has improved over the years. Few brands still use the
-10dBV convention introduced IIRC by Tascam any more for example.

I guess 'semi-pro' would ber well represented today by Behringer et al. Not bad
performance at all.

Graham

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

David

I was wondering what the resistor values should be.

Bob

"David Satz" <DSatz@msn.com> wrote in message
news:e6a68193.0408301750.23bc0ad@posting.google.com...
> sodderboy wrote:
>
> > [ ... ] Sometimes standalone mic pre's or smaller consoles do not supply
> > enough P48 juice.
>
> Quite true, unfortunately.
>
>
> > It should be 48vDC between XLR 1 & 2 and 1 & 3, tested with the mic
> > connected.
>
> No, no, no! 48 Volts is the _open-circuit_ (unloaded) voltage. A board
> or preamp that supplies 48 Volts with a microphone connected could well
> damage that microphone severely, depending on the microphone of course.
>
> There is a 6.8 kOhm resistor in each of the modulation leads of a properly
> constructed 48 Volt phantom power supply. When a microphone that draws
> 2 mA is connected, each lead will carry 1 mA and the resistors will drop
> about 6.8 Volts; in that case the voltage with the mike connected would be
> a little above 41 Volts. That is the proper behavior of the circuit.
>
> For a microphone that draws 4 mA such as a Schoeps CMC 5-- or 6--, the
> voltage drop will be twice as great--ca. 35 Volts with the microphone
> connected. The Shure KSM series microphones draw about 5.5 mA apiece,
> some CAD Equiteks draw 8 mA, at which point more than half the original
> 48 Volts is being dropped across the phantom resistors!
>
> The winner and still champion is Earthworks at 10 mA apiece--which means
> 5 mA per 6.8 kOhm resistor for a drop of 34 Volts, leaving only 14 Volts
> for the microphone itself to work on. Wacky, wacky.

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

"Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
news:4132E71A.7CEB0F8D@hotmail.com...
> TonyP wrote:
>
> > "Pooh Bear" <rabbitsfriendsandrelations@hotmail.com> wrote in message
> > news:41309180.11A4929A@hotmail.com...
> > > As I mentioned, the 'taper' - resistance versus rotation of the pot
> > > makes a great difference here. All my
> > > current designs use 'special' tapers that are made to order. There's
> > > nothing stopping anyone else doing this.
> > >
> > > Even so, the last 30 degrees or so of pot rotation usually correspond
to
> > > a large part of the gain range. This
> > > can be fixed only by a 'super special' taper pot !
> >
> > If you want a *linear* gain increase wrt pot rotation, you don't need a
> > special taper at all.
>
> A linear adjustment of gain is no use whatever. Gain is usefully measured
in
> dB. A linear pot would cramp *all* the useful gain adjustment into a tiny
> section of the clockwise rotation.

Where did I say *I* wanted linear gain? Try reading before posting.

TonyP.

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

"David Satz"

> A board
> or preamp that supplies 48 Volts with a microphone connected could well
> damage that microphone severely, depending on the microphone of course.
>


** Some desks use a centre tapped input transformer to supply 48 volts
phantom to the mic.

No resistors in sight.

What mic do you say will be harmed by this ??



............... Phil

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

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:2piib2Flj32cU1@uni-berlin.de...
>
> "TonyP"

> > If you want a *linear* gain increase wrt pot rotation, you don't need a
> > special taper at all.

> ** In the case of most mic pres that is not so.
>
> The gain control is a variable resistance connected in such away that
the
> gain of the circuit in an inverse function of that resistance.

This is true, but not the only way to do it.

TonyP.

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

TonyP wrote:

> "Phil Allison" <philallison@tpg.com.au> wrote in message
> news:2piib2Flj32cU1@uni-berlin.de...
> >
> > "TonyP"
>
> > > If you want a *linear* gain increase wrt pot rotation, you don't need a
> > > special taper at all.
>
> > ** In the case of most mic pres that is not so.
> >
> > The gain control is a variable resistance connected in such away that
> the
> > gain of the circuit in an inverse function of that resistance.
>
> This is true, but not the only way to do it.

Do *please* say how you would do it. In a practical circuit giving regard to
noise figures.

Graham

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

"Phil Allison" <philallison@tpg.com.au> wrote in message
news:2pik4aFloh45U1@uni-berlin.de...
> > This is true, but not the only way to do it.

> ** Classic Tony the Prick zero information content reply.

Even when I agree with you I get abused. So you think there is NO other way
to do it?

TonyP.