Live audio - avoiding feedback

Jon Fairhurst · January 30th, 2008, 05:16 PM

Quote:

Originally Posted by Chris Hocking

You're going to be mixing the show so you HAVE to trust your ears! If you don't, well then there's really no point having you behind the desk!

Ha, ha! Good point!

Fortunately, I do trust my ears to a large degree. I can hear a resonance and have a reasonable first guess as to the frequency range.

One thing about an RTA is that I can train people in the IT department (they own the system) to use it. I don't know that I can train their ears. They're good with PCs though. I should be able to come up with a cheap RTA solution to run on a laptop for them.

Next step: get a 31-band EQ...

Jon Fairhurst · May 15th, 2008, 06:30 PM

We just completed another meeting in the same room with the same speakers, and it was a complete success.

I arrived earlier and set the speakers further forward. I got the president's microphone (Countryman E6) properly fitted. We got a snake and positioned the mixing board properly. I got a 31-band EQ and found the problem bands before the meeting started. The results were ideal.

Still, our president has a very gravelly voice, and he arrived late enough that I didn't get a sound check with him. As soon as he stepped away from me, he muted the wireless transmitter. The first I heard his voice on the system was live.

Still, I was able to ride the levels and keep it just shy of feeding back. It didn't take long to balance the lo/mid/hi EQ for his channel to get a more pleasing sound and a bit more volume.

One adjustment I need to make is to get a hotter signal into the EQ, so I can hit the detection LEDs. As it was any EQ adjustment was by ear only.

Others used a handheld mic. Unfortunately, I was only able to coach one person on where to hold it. Two of the speakers held the mic much too far away, but I was able to get enough level without feedback anyway.

FYI, the EQ we purchased is the Peavey QF131. It's not high end by any means, but killed the resonant frequencies and was very quiet, so it met all of my requirements.

http://peavey.com/products/browse.cf...h%20FLS(R).cfm

Thanks to everybody for your earlier feedback...

May 15th, 2008, 06:30 PM	#17
Jon Fairhurst Inner Circle Join Date: May 2006 Location: Camas, WA, USA Posts: 5,513	Success!!! We just completed another meeting in the same room with the same speakers, and it was a complete success. I arrived earlier and set the speakers further forward. I got the president's microphone (Countryman E6) properly fitted. We got a snake and positioned the mixing board properly. I got a 31-band EQ and found the problem bands before the meeting started. The results were ideal. Still, our president has a very gravelly voice, and he arrived late enough that I didn't get a sound check with him. As soon as he stepped away from me, he muted the wireless transmitter. The first I heard his voice on the system was live. Still, I was able to ride the levels and keep it just shy of feeding back. It didn't take long to balance the lo/mid/hi EQ for his channel to get a more pleasing sound and a bit more volume. One adjustment I need to make is to get a hotter signal into the EQ, so I can hit the detection LEDs. As it was any EQ adjustment was by ear only. Others used a handheld mic. Unfortunately, I was only able to coach one person on where to hold it. Two of the speakers held the mic much too far away, but I was able to get enough level without feedback anyway. FYI, the EQ we purchased is the Peavey QF131. It's not high end by any means, but killed the resonant frequencies and was very quiet, so it met all of my requirements. http://peavey.com/products/browse.cf...h%20FLS(R).cfm Thanks to everybody for your earlier feedback... __________________ Jon Fairhurst