You must have a wrongly placed component if you need to run the crash through a mixer to get a decent level. I normally have the volume at around 50% maybe less. With a scope it'll be quite easy to find fault as the ride and cymbal are identical circuits.

Do you know how can i do to detect the wrong component? i've already checked a lot of time the value of the resistors (by color), i've changed one transistor, i've reversed the ride and crash chip, and i have still a low volume on the crash circuit (on the board so it's not the chip).
I have a scope if it can help...
How to do comparison test with both circuit and a scope please?
Thanks

The best way I find for check part location is by writing down the part locator numbers (R466, R467, C50 etc) and visually checking and using a resistor calculator (https://www.digikey.co.uk/en/resources/ ... ode-5-band) to determine the value, writing this down and once I've collected all the parts values I check against the BOM - sounds like you have already down something similar already.

For determining where the fault lies using a scope, using the schematic I would start tracing the signal from its source - in your case IC62, the eprom - against the ride and looking for where the signal drops suddenly lower. At first you will not need to check each component but would be best to direct your time at measuring at the transistors to determine a general area.

I had an issue the other week with a build where the hihat dropped in considerable volume - completely unusable - this turned out to be a bad 798, the matched transistor. Once I found the fault to confirm it was that part I checked continuity with a DMM which showed up a fault on one side. It may be worth a quick check there before you get the scope out. The 798 is part of the envelope and VCA (anti log) circuits which in turn boost the volume.

Hope this helps

Thanks a lot, i will check it soon when i have a moment...

Output at Q78 and Q76 is the same, so the problem is after.
Output at IC64A is low whereas output at IC65A is ok.

So the problem is between, it should be the M5218... but i already replaced it!

Do you know how to test the M5218? Could it come from the pot?

Thanks

Another solution is to change the resitors R525 and R526 on the IO-Board near the Crash Jackconnector.

- R525 change to 5K8
- R526 change to 4K7

The volume will be better and it's still to low you can make lower the resistors until 1K0.
I had done the same also with another instruments when the volume is to low.

Cheers Jos

Take a look at the resistor before to confirm.

Hi,
I've tried changing the M5218 but it doesn't work better...

I've tried lowered the output resistors, and it doesn't do much...

Any idea?

Output at R445 and 5446 is the same. Output at IC 65 is not good, so the problem is the M5218 i just replaced. So i thought it is the pot but i tried shunt it with another one but the result is the same.
So the only way is a cutted trace or something like that...
I'm totally confused now...
If you have any idea
Thanks