Total recall help please

[atodovax]

Hello everyone. I built a total recall and it sounds pretty good but it has too much distortion. Im having distortion signal on ic6s input. Is that normal or should i have clean sigal there? Thank you very much!!

[thomasha]

I would guess clean, and lower amplitude, so that the MN won't distort.

If you have an audio probe check where the signal distorts. Could be a wrong resistor or a cold solder.

At which voltage is the MN biased?

[madbean]

The signal should be very loud and slightly distorted at pin6. That is due to the compander boosting the signal before the pre-empahsis filter and BBD input. However, the signal should be cleaned up significantly after the "expander" section (pins 10 and 11 of the NE570). If you still have significant distortion at that point, you need to start looking closely at your resistor values and make sure they are all correct, compare you voltages with the reference ones and also make sure you do not have GAIN1 and GAIN2 trimmers set too high (and obviously the Level control will generate distortion when it is cranked up).

[atodovax]

Thanks everyone, im going to check everything later and report again

[thomasha]

Uhm, so that's how the compander expander pair works... should have checked that before.

I was trying to build a minimal bbd delay, but it's really hard. Chorus or flanger circuits work without the compander, but delays won't, they are just too noisy.