Peavey Stereo Chorus 400 - No Vibrato

[Jazz P Bass]

I have a Stereo Chorus 400 & the vibrato & tremelo are 2 distinct sounds.
Both can sound good at low settings but get really warbly at higher settings.

[lowell]

Thanks JPB. So it seems both effects are working as twiddling with the controls for tremolo works, and same for chorus. However, and please let me know if this is how it’s SUPPOSED TO work: when I click the foot switch, I either have no effects, or both. I can turn the chorus to zero and use the tremolo and vice versa… that’s fine… but I thought it odd that the foot switch doesn’t switch BETWEEN the 2 effects. It either turns both off or both on.

normal?

[Enzo]

What are you expecting from a single switch? Cycling off/chorus/trem/both/off etc?

Look at your schematic. Upper right. U16d,b are the chorus clock with depth control. U17 is the vibrato clock, with depth control. NOte they come together and drive the SAME control path through U61a,U15, U14. All that clocks the bucket brigade IC, U13. U13 is the only audio path through ALL of that stuff. There is no switching for trem versus chorus.

Next the chorus/trem output from U13 feeds through Q11, Q12, and compander U8a, U11b. From there, your effects signal is fed to JFET Q10, which switches it in or out of the preamp channel 2 output. That is the only effects switching in there. SO yes, it is normal: both or neither.

[lowell]

Yeah I shoulda looked at the circuit, that’d make sense. My bad. Thanks for the detailed reply!

[Enzo]

It is a complicated circuit, and until I had to explain it, I never gave it much thought.