AW: [sdiy] OTA's and phaser question

[Nils Pipenbrinck]

Peter Blackett wrote:
> I just finished repairing an electro Harmonix small stone phaser , and
> when its working its sounds nice and warm,due I guess to it adding in a
> small amount of distorsion.
> previously I had thought of making a stereo version
>  ( more for studio use ) maybe like the moog stage phaser ? but I found
> that the ca3094 ic's aren't made anymore.
> but the Lm13700 ic's seem to be available still.

Hi Peter,

I cloned the small stone myself, and I just used the cheap CA3080 with a
MPSA-13 tranny as darlington buffer. Since I still own a hand full of CA3094
chips I was able to do a comparision of the original against the
replacement.

They sound exactly the same.

imho the CA3080 + external tranny works just fine in this circuit, and it's
a lot cheaper than the LM13700. Also you don't need to recalculate the
phase-shift stages :)

Nils