SRE330 debugging help needed

[opsaxell]

Hi !

Just got my SRE330 completed. The calibration went ok, except for the SLOW part. I was able to get only about 4V.
And then the sound, its somehow not as rich as I was expecting based on the sound examples.
So I suspect there is something not working.
Could you point me to some measurements that I could make to check it?

Here is a quick video I made of some measurements/tests:
Its a square wave input, measured from the right output channel.
All rate/depth are at 0 in the beginning.
Mode is multi, stereo.
Balance at dry.
Then I start turning the balance towards wet (I guess I left it at somewhere midway)
Then flick the multi mode to dual and then to quad.
Then turn in some tri/chorus depth, then some tri/chorus rate.
And then flick the multi mode to dual and then back to stereo.

Thanks in advance,
o-p

[Synthbuilder]

The calibration went ok, except for the SLOW part. I was able to get only about 4V.

When calibrating the SRE330 make sure your scope is set to DC input and not AC input. This has happened for at least two folk who couldn't get a high enough signal for the slow calibration.

The way to tell if the slow calibration has worked is to look at the three outputs on pin 7 U14, pin 1 U14 and pin 1 U15. All three outputs should have the same amplitude at around 10V peak to peak and be sine wave like. If they don't all match in size and shape you have a problem somewhere. The frequency should be around 0.6Hz

Could you point me to some measurements that I could make to check it?

When you monitor a single output of the SRE330 in dual and stereo modes you should see only one delayed signal mixing with the input. In quad mode you should see two delayed signals mixing with the input. The video seems to show that but it's a bit hard to tell for sure as it's only one frequency and the modes are switched quite quickly.

If you use a lower input frequency, 40Hz is a good one to use, you should see more easily the delayed signals against the input.

It's worth nothing that if you are listening to one output, and not in stereo, the chorus effect will be much less pronounced. This is especially true in three phase mode. If listening to one side only the dual and stereo modes will sound pretty much the same as each other, and will behave much like a Boss CE-2 chorus stomp box when used with triangle modulation.

[opsaxell]

ah thank you! it was on AC, now it worked! and the sound is amazing!
I think this is a really really high quality design. which in turn makes it as easy build as it can be.
now a bit of a break from building to actually playing.
then I think I'll dive in to modular via Oakley eurorack modules, this gave me such a good impression of the quality


// o-p