Need help on this Caline CP-58

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Magikarpet
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Post by Magikarpet »

So i bought this pedal (which is based on a Tech 21 British), and has this cab sim that i personally dislike. Is there any schematic or layout for this pedal so i can bypass the cab sim?
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stolen
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Post by stolen »

Hello!

There doesn't appear to be a trace yet - but this here might be useful, apparently many of the series use the same layout with different component values? However we did not read much of the thread, might've understood that wrong. If we strip away all the strippable bits, we arrive at a 8 OPA schematic, including cab sim - we can only see 6 on your pictures though and no transistors, so it might be different. But then again we can't quite make out what's under all these pots.

Be this as it may, you could use a signal probe to listen to all the OPA outputs, it is pretty certain that they used a industry standard speaker sim topology, so that the speaker sim receives signal from a buffered output and returns it from a buffered output as well. If you can locate which actives are introducing the filter, you can locally trace that bit and in the simplest case just rip out a few capacitors. We're afraid we can't help with the tracy bits remotely, but if you have confidently located the speaker sim and beeped through adjacent components we can advise on how to progress. Of course, cutting the speaker sim output trace and make it switchable is an option too.

Since the amount of actives is low, we suspected for a moment that they might have cheaped out and added a purely passive 1st or 2nd order high cut, but then again this direct demo suggests otherwise.

All the best,
stolen

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Magikarpet
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Post by Magikarpet »

UPDATE:
I went to do a little bit of research and i found this:
JOYO JF-13/14/15/16

The circuit looks to be the same but the layout is diferent.

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Post by Magikarpet »

stolen wrote: 21 Sep 2021, 09:47 Hello!

There doesn't appear to be a trace yet - but this here might be useful, apparently many of the series use the same layout with different component values? However we did not read much of the thread, might've understood that wrong. If we strip away all the strippable bits, we arrive at a 8 OPA schematic, including cab sim - we can only see 6 on your pictures though and no transistors, so it might be different. But then again we can't quite make out what's under all these pots.

Be this as it may, you could use a signal probe to listen to all the OPA outputs, it is pretty certain that they used a industry standard speaker sim topology, so that the speaker sim receives signal from a buffered output and returns it from a buffered output as well. If you can locate which actives are introducing the filter, you can locally trace that bit and in the simplest case just rip out a few capacitors. We're afraid we can't help with the tracy bits remotely, but if you have confidently located the speaker sim and beeped through adjacent components we can advise on how to progress. Of course, cutting the speaker sim output trace and make it switchable is an option too.

Since the amount of actives is low, we suspected for a moment that they might have cheaped out and added a purely passive 1st or 2nd order high cut, but then again this direct demo suggests otherwise.

All the best,
stolen
UPDATE:
So i just followed the image and soldered one coble from pin 3 of the volume pot to R24, IT WORKED.
Thanks for the help anyways.

Ps:. and removed R28

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