Dumitru Stama wrote: > I just realised something. If i use three op-amps in succession i will > get an inverted signal a the end. Same with only one op-amp. > On the other hand i saw on Jinx's schematic that he was using only one > transistor wired as common emitter which inverts a signal. > Am i going crazy here or the electret really spits out an inverted > signal of what it picks up ? It doesn't matter if you only have a signle audio channel. A inverted audio signal sounds exactly like the non-inverted orignal. The inversion phase only matters if you have multiple channels, as in a stereo system for example. Even then the total inversion doesn't matter, only that all channels be inverted or not inverted the same way. ****************************************************************** Embed Inc, Littleton Massachusetts, (978) 742-9014. #1 PIC consultant in 2004 program year. http://www.embedinc.com/products -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist