HPF for 1176

What would be the way to add a HPF to a 1176 ? I tried to insert this circuit before r56 but i get
main signal HPFed. It sort of works after c 17 but a bit weak and distorted. Any ideas greatly appreciated.
Thank you.

Reduce the value of C17... that's a simple High-pass in itself...

That GSSL circuit has the wrong front end.... Int he 1176, you've got the threshold shifting with ratio by switching in a BUNCH of resistance before C17, and that GSSL circuit is an inverting op-amp with -6dB at 20kΩ input impedance... it's all going to be wrong, I tell ya, so far as the threshold changing with ratio.

You'd need (at the very least) to apply the input at the noninverting input, and provide a 1MΩ DC reference to mid-rail... -exactly HOW were you powering/referring the circuit before?

Keith

[quote author="SSLtech"]Reduce the value of C17... that's a simple High-pass in itself...
Keith[/quote]

thanks, that is exactly what I've done (a few minutes ago) and it works quiet O.K. so I'll stick to it. as for the “unhappy hijacking gssl hpf attempt” i was powering it by the +/-18vdc rails... :thumb: