How do I avoid feedback when I am white noising a guitar amp. Tried this technique after your video on guitar recording but got an unpleasant feedback with logic.

Hi Peter This comes down to your audio interface - how many outputs can it handle? If its only two (L+R), you're going to get feedback. This is because: 1. The white noise (generated in Logic) comes out of the stereo outputs (1+2) 2. This signal is sent through the amp and picked up by the mic 3. The mic signal goes back in to Logic 4. In order for you to hear the mic signal through headphones, the output of the mic signal has to come out through the stereo outputs (1+2) - but outputs1+2 are going back into the amp, through the mic again, and back into Logic! Instant feedback. There's two solutions I can think of (there may be more - Rounik and Ski might chip in) Solution 1: Use an audio interface with multiple outputs. Solution 2: Record 20 minutes of white noise onto a track in Logic. Bounce the track as a Wav file then burn it onto CD. Cable a CD player into the amp and play the white noise that way. This gets rid of the loop - the signal path now goes 1. CD player plays white noise into amp 2. output of amp goes into mic 3. mic goes into Logic 4. mic signal comes out of Logic output 1+2 into your headphones. It doesn't need to be a cd player - you can bounce an MP3 and use your ipod instead - whatever, as long as the source of the white noise isn't Logic. Hope that helps! Cheers Hamish

Thanks for inviting my input, but I'm not familiar with this technique. -Ski-

Thank you Hamish H. I will try the recorded white noise since I only have an Apogee Duet with two outputs. But here comes next question. I can rout my output signal from my Duet to only left or only right channel. Can I then send white noise to a guitar amp trough my left channel and the mic in to Logic and then out to the right channel to my headphones?

Hi Peter I'm not too familiar with the Duet, but I think that even though you can split the main output into two channels, the actual headphone output will always be in stereo. I guess you could listen to just one of the headphones in a DJ style, but in this case you really want to be listening to the headphones without any distraction from the amp. Hope that helps for now, I'll see if I can find out some more about the Duet. Hamish