Re: PA Powered Amp Gain Settings Question

Professional audio recording and studio engineering, post #46,567
Author:
Date:
Subject:
 Laurence Payne
 2008-07-18 14:54:16
 Re: PA Powered Amp Gain Settings Question
On Fri, 18 Jul 2008 06:17:41 -0700 (PDT), [email protected] wrote:

>Thanks for the replies and info,
>
>I'll checkout that handbook to see more about eliminating the
>feedback. Currently it's a very basic setup and it's worked for years
>but I recently started wondering if it would be possible to get more
>sound and better quality with less feedback.
>
>We are practicing in a converted garage so it's a fairly small space
>which makes 'placing the mics' and all such things rather difficult.
>Currently the mics are in the center of the room because that's where
>we have space and because besides myself the two guitar players and
>singing backup.
>
>There is currently no EQ, compressor's, limiters, etc on the system
>just a mixer, power amp and two loudspeakers. I've been thinking about
>getting an EQ or compressor but money is limited so I'm trying to
>maximaze what I can before buying more gear.

OK. Well, you're talking PA - there's no-one out front to hear it!
You just need monitors. You need the speakers to be pointing at the
performers, as close to their ears as possible while still keeping all
microphones pointing AWAY from the speakers. The classic position to
achieve this is placing them on the floor in front of the mic stands,
angled up. If the drummer complains he can't hear give him one of the
speakers all to himself, aimed straight at his face.

If you have trouble getting guitars etc. to turn down to a realistic
level make sure THEIR personal amps are aimed straight into their
faces. It's only the guitarist who wants to hear himself THAT loud
:-)
Author:
Date:
Subject:
 Scott Dorsey
 2008-07-18 10:16:08
 Re: PA Powered Amp Gain Settings Question
<[email protected]> wrote:
>
>I'll checkout that handbook to see more about eliminating the
>feedback. Currently it's a very basic setup and it's worked for years
>but I recently started wondering if it would be possible to get more
>sound and better quality with less feedback.

Feedback is caused by sound from the speakers going into the microphones.
It can be reduced by using more directional speakers and microphones, by
careful placement of speakers (and that includes monitors) and microphones,
and by avoiding reflective surfaces around the stage area (like big cement
walls behind the band that take the sound from the monitors and reflect
it right into the mikes).

>We are practicing in a converted garage so it's a fairly small space
>which makes 'placing the mics' and all such things rather difficult.
>Currently the mics are in the center of the room because that's where
>we have space and because besides myself the two guitar players and
>singing backup.

Your goal, then, becomes to keep the backline levels down, so the PA
doesn't need to be up very high.

>There is currently no EQ, compressor's, limiters, etc on the system
>just a mixer, power amp and two loudspeakers. I've been thinking about
>getting an EQ or compressor but money is limited so I'm trying to
>maximaze what I can before buying more gear.

If your problem is feedback, an EQ with real notch filters (not a cheap
graphic) will help you a lot. There are a bunch of automatic feedback
eliminator boxes out there that are basically just automated notch filters...
they find the frequency where the feedback takes place and drop a notch
there. As long as you don't move anything around, the feedback frequencies
stay in the same place, but move a mike a foot and they can change. So
the equalization is something you want to use only AFTER you have done
everything else to reduce feedback.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."