[sdiy] Module Placement - Dist > Filter or vice versa

[Roy J. Tellason]

On Thursday 18 November 2004 03:43 pm, Scott Gravenhorst wrote:

> >For the signal?  And what kind of signal levels are feeding that?

> +/- 5 volts.  Then through the attenuator down to +/- 50 mv.

The 10VP-P I was thinking of...

> OTAs can't handle any more than that either, I just looked at the LM13700
> data sheet, VCAs and VCFs use heavy attenuation of the input signal to
> avoid distortion.  A simple single stage VCF example used a 100K and 200
> ohm.

Good thing I have LOTS of resistors on hand!

> >> I'm looking at a +/- 50 millivolt AC input signal after the attenuator.
> >> This level satisfies the H11F1 distortion requirements.

> >I've not done terribly much with this stuff,  and am too used to thinking
> > of the sorts of amplitudes one finds running around in synths,  10VP-P or
> > something.  The rest of it is hi-fi stuff at "line level",  which is
> > what, several hundred mV?  And I've worked with pro sound stuff,  but not
> > in a lot of years,  most of that was not too far from there and with lots
> > of headroom.
> >
> >I'm just a little concerned about things getting buried in the noise,  or
> >similar.

> Me too, but it works with OTAs.

Maybe they're dealing with currents instead of voltages or something?  I've 
never really looked at the way those things work...