Zero Point SDX, help needed: Why the delay distorts when strumming loud?

[Teddy]

I checked resistor values R8-R20, they are correct

what's next?

And thanks for replies, it's great to have support.

Thanks,
- Teddy

[Teddy]

I checked resistor values R8-R20

they are correct

what's next?

Thanks for your replies, i really am thankful to get tech support.
- Teddy

[kothoma]

1) You are sure your guitar signal is not simply too hot?

2) Take a magnifying glass and closely inspect your soldering. There may be unwanted bridges or cold joints. Take a continuity meter and check suspect points.

3) Try to listen to the delayed signal at different points (between C16/R14, after C31/before the mode switch for a start) to find where the signal starts to degenerate.

[Teddy]

I will do the following, thank you.

I'll let you know, when i'm done

Thanks,
- Teddy

[kothoma]

Path switch on / off... works a bit akward. It makes the first repeat louder.

Yes, at least it could appear like that, because then the first repeat is unfiltered and has more highs.

Just to make sure, this louder first repeat is the most distorted one?

[kothoma]

One more idea. This distortion can be heard at all mix levels where you still hear delays?
(If not: check R40).

[Teddy]

Yes, the first repeat is the most distorted one.

Also, i think, the feedback pot is way too sensitive.
It oscillates before 12 o clock

-Teddy

[kothoma]

I will do the following, thank you.

I'll let you know, when i'm done

Glad to be of help. Good luck!

[Teddy]

Hello....

Just asking, how sensitive the feedback pot is supposed to be?

I think it's oscillating before 12'o clock

Thanks,
-Teddy

[kothoma]

Yes, the first repeat is the most distorted one.

Also, i think, the feedback pot is way too sensitive.
It oscillates before 12 o clock

Everything looks like your delayed signal level is way too high. Continue as proposed.

[midwayfair]

It's distorting either because of the diode clamp across the feedback pot or simply because PT2399s will distort with a signal larger than 2.5v. It's more likely to be from the feedback diodes since it doesn't distort as much when you flip the path switch (which redirects the first and thus loudest signal) and even the bare signal from a guitar is large enough to clip them(never mind one that's amplified by U1).

[Teddy]

Ok... i tried the ZP SDX with a drum machine, output level @ max
i hear no distortion ! crazy...

Then with a guitar, distorts badly.

I really don't know what to do..

I built myself a simple audio probe, to listen to the signal.

But i don't know really, what to do.

Thanks,
-Teddy

[Teddy]

Hello!

Thanks for giving me info on how to fix the SDX pedal.

I'm just thinking, that should i post a sound sample?

Off topic:

How to attach a sound file to the forum?

Thanks,
-Teddy

[Teddy]

fast_delay.zip

[Teddy]

Here's a second sample,

a slower delay setting

-Teddy