Preamp Usage - Clipping at Mixer

  • Thread starter Thread starter David Katauskas
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David Katauskas

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Mabye my signal chain is just stupid and there is just something fundamental that I'm missing.

I just got a new preamp (m-audio tampa). When putting it in my chain (SDC -> tampa -> mixer -> soundcard), it is too easy to peak the signal at the mixer...even when using some slight compression for limiting. If the gain is pushed slightly on the preamp, the mixer peak light goes on with conversation level speaking. The VU meter on the preamp barely moves.

The only reason that I still have the mixer is to convert the balanced line from the preamp into a stereo line for the soundcard.

What am I doing wrong...or is this normal?
 
There's a couple of things there I'm confused by. What do you mean to convert balanced into stereo? Do you mean you have like an onboard soundcard with a minijack line in? Just take an unbalanced mono guitar lead from your Tampa into the soundcard (with a little adaptor of course).

What are you plugging into on your mixer? Mic or line? Does your mixer have a pad on the inputs? If you're using quiet sources and not doing anything silly on the Tampa, you shouldn't have a major problem with your mixer as long as you plug into the line input (which usually just constitutes a 20dB pad and then goes back into the mic preamp). Only problem with this is that you negate the coolness of your Tampa pre by running back through your mixer one afterwards.

This is a really good article on gain staging that you might find useful:
http://www.soundonsound.com/sos/oct00/articles/soundcard.htm

Does that help at all?

Nik
 
noisedude:
First, thanks for the reply and link.

Yes, I'm using the mixer simply to convert the XLR output form the preamp into an 1/8" Left/Right signal to the soundcard. I'm bypassing the onboard mixer preamps and only using the faders.

The thing that is confusing me is, when trying to set the gain on the preamp to near clipping levels (nearing 0db on the preamp VU output meter), that output from the preamp is then way too hot for the mixer (according to the peak light on the mixer). Maybe I should just ignore this light...as it's expecting a mic level input? Now that I'm thinking about it, I could also try the 1/4" balanced input on the mixer to see if the same thing occurs.

btw - the 20db gain pad on the preamp is off
 
My guess is that you are right about using the 1/4" line level input. The output of your preamps may very well be too hot for your MIC level input. If you have inserts on your mixer channels you could also try sending the signal there which should bypass your mixer preamps. Just a few suggestions.

-Jamie
 
Get an XLR-F to 1/8" cable, bypass the mixer, and record to a mono track in your software. Running through the mixer is just degrading your sound further. And, there is no need to record a mono source in "stereo." It just wastes disk space.
 
Thanks for the replies...I'll do that tonight when I get home.
 
is your mixer -10 or +4? The Tampa kicks out a +4 signal

Also.... if all your soundcard has is a stereo line in I suggest you upgrade as soon as possible, it's bound to be degrading your signal and definately won't be able to accept +4 levels
 
It seems like all the usual suspects have gotten well covered so far in this thread. As has been discussed, the most likely causes are running a line level signal (the output of your preamp) into an input on your mixer which is expecting a mic level signal. You are almost certainly doing this because you are taking the XLR out of the preamp into XLR inputs on your mixer, which is most likely a mic input. You will indeed solve this problem by putting the preamp output into a line level input on your mixer (which will probably be a 1/4" input).

Second, the suggestion about getting a soundcard with 1/4" inputs is *really* good. Those 1/8" mini plugs are just awful, and you'll be a lot better off if you can record directly from the output of your preamp to a soundcard.

What mixer are you using, by the way?
 
Yeah, my Christmas list consists of GC gift cards exclusively. So, I'll have to wait a bit. But with that I'll be purchasing a real sound card, acoustic treatment and an SM7b. :D
 
Big Kenny said:
And what are you getting all your friends at HR, hmmmmmmmmmmm?
Click to expand...
Kenny I want you to buy me an 'In His Name' t-shirt. And I want some kinda sarcastic slogan one from Cressrock.
 
scrubs said:
Get an XLR-F to 1/8" cable, bypass the mixer, and record to a mono track in your software. Running through the mixer is just degrading your sound further. And, there is no need to record a mono source in "stereo." It just wastes disk space.
Click to expand...


I second this.




Hear, Hear!
 
One important thing you might have overlooked in the manual is that the tampa registers 0 VU at +26dBu

My guess is, this is where your problem is. So your output dial should hardly be moving off the bottom pin at all.

Hope that helps
 
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