Hi guys

I see this chip in intercom design, I can understand every single word in the description, but I still don't know why this chip is needed.

http://www.analog.com/en/audiovideo-products/audio-amplifiers/ssm2166/products/product.html

PS: I don't know much about audio stuff.

Thanks guys!

 

it is used to compress the signal from the microphone (compression changed the peak to average signal level) , this gives more aparent output, but also distorts the signal a bit. it also has an automatic gain control circuit that tries to hold the output signal level constant.

 

As stated in that 'understood' description... to improve vocal clarity & to provide adjustable compression characteristic. Also to provide preamplification &/or buffering of microphone plus automatic limiting all in a single IC.

And it is not really needed. You could do all that with several 12AX7s.