> Can anything be improved (sensitivity/intensity) by changing R2/R5? Not really. R2/R5 are doing very little by the time you have reduced R1/R4 to 10k. This is the simple circuit. The more complicated one with opamps adds gain so can be very sensitive but then is not so straightforward to build and needs a separate power supply. Keith.
Message
Re: dtxpander for 3zone pads?
2005-10-23 by Keith