Narrow band audio noise reduction with the SSM2000

[hfmobile]

Is there anyone who has experience with narrow band audio noise reduction with the SSM2000? This IC was designed for noise reduction of HiFi-audio but my application is noise reduction in the range of 300Hz - 3000Hz. Is there, beside DSPs, an analog alternative for the SSM2000 or an alternative analog noise reduction circuit? Of course there IS a reason why I do NOT want to have a DSP in this circuit...

 

[VEBill]

You might want to look at the ARRL Handbooks from the pre-DSP days (1970s-1980s). You'll see various analog noise reduction circuits using garden-variety components.

Somewhere back in the day, there was a design that used the Vf drop of diodes to gate-off the low level hiss noise while allowing the voice through. Personally, I find the on-off gating more annoying than the hiss.

Also, you could research 'compander' circuits which similarly COMpress and exPAND the dynamic range of audio signals.