e-licktronic Forum

Hoping someone can guide me in the right direction here since I can't find anything wrong visually. My Yocto is complete and working awesome everywhere aside from the handclap. There are a couple issues with the clap channel, one is that when the clap volume is turned up there is a constant white noise almost like tv static. All of the other voices are dead silent, but the clap voice is quite noisy. Secondly, the clap sound barely works, it does trigger a quiet, pathetic fuzzy sound, but it's not the clap. The maraca sound does work like normal, or a lot more normal than the clap at least, but the clap is basically nonexistent.

To sum it up, the clap/maraca channel is noisy when the volume is turned up, the clap barely triggers any sound at all, and the maraca works as normal. I have reflowed everything in the clap section and don't see any bridges, the rest of the Yocto works perfectly.

Ideas?

Thanks!

Have you tried adjusting TM3?

Yes, TM3 has no effect an anything. The slight fizz sound that happens when the clap is triggered is not changed by the trimmer.

Update: I've spent some more time going through everything and it turns out that the rimshot is also very quiet. Not sure if that could be related, but the claves are normal volume and tone while the rimshot is barely audible, but the tone is correct.

I will keep this thread updated as I figure out what the problems are, but if anyone has any advice on where to begin aside from just brute force rechecking every component in the affected sections I'd appreciate it

Thanks!

So after realizing that the rimshot was quiet as well I assumed that there might be a shared component between the two so I went through the rimshot section more carefully, and much to my embarrassment I found a solder bridge between r363 and c128. I fixed that, and now the fizing sound that was the clap before is louder and a lot more claplike, but it's still wrong, and the clap channel is still really noisy. The rimshot is also still extremely quiet. TM3 still has no effect on sound. Also, the strangest part, after being powered on the clap produces no sound at all for several seconds, then slowly "charges up" and starts making sound... strange.

My assumption is that that bridge fried a transistor or IC. Next step is to look through the schematic for the likely victims.

As always, if anyone knows off the top of their head what components are involved in those two pathways that are likely to cause this problem I'd love to hear

This is what I get for using my gigantic blunt tipped 40 watt iron to assemble a tiny board I guess. I recently moved and can't find most of my soldering stuff... got a bit impatient... I'm probably lucky that there weren't more bridges honestly haha

UPDATE: I was unable to solve anything further by reflowing/checking for bridges so I ordered another ba6110 for the clap section and lo and behold my clap works now. That bridged solder connection either fried the clap's amp or I just got a bad IC, but either way it's fixed. Unfortunately this did not also fix the rimshot volume problem, it is still super quiet, and I'm not sure where to go from here to address that problem. I replaced all three of the op amps in that section with TL072's and there is no change, it is still super quiet.

Open to suggestions. As always, I'll update as I make progress.

Have you read this topic regarding the rimshot?

viewtopic.php?f=16&t=161&p=437&hilit=rimshot#p437

No I had not seen that, will try it out when I get home, thanks for the lead!

I also had the clap not hearable one time. It was a solder too close of the CP level pot.

About the RS, it could be related to what define its volume, so something around the level pot or amp.