Hi everybody,
After finishing building the kit, almost all is sounding very well except the hihat and cymball (but this is most noticeable on hihat). The sound is very different from original TR-808.
I've checked the components, readjusted TM1 and TM2 as indicated many times ( and Cowbell sounds good).
Do you have any advices?
Thank you!
Hihat and cymbal not sounding as they should [SOLVED]
It should be a tuning problem.
It had the same issue, Cymball and HiHats sounded lower in tuning than Yocto samples and original TR808 samples, even if adjustment of TM1 and TM2 looked ok on my scope.
I found this thread on the forum : viewtopic.php?f=16&t=202&p=1147#p1147 and directly readjusted values from TM1 (1,78ms instead of 1,85 ms) and TM2 (1,19ms instead of 1,25ms) than noticed that tuning was almost ok. then, I trimmed by ear until it sounded the same as samples. Cowbell sounded ok for me before readjustment, but was actually better after that.
Well, I could have probably fixed that by replacing components, but this method did the job for me.
Maybe just try this or if you think the problem is somewhere else, then you should upload a few samples.
Hope this help.
It had the same issue, Cymball and HiHats sounded lower in tuning than Yocto samples and original TR808 samples, even if adjustment of TM1 and TM2 looked ok on my scope.
I found this thread on the forum : viewtopic.php?f=16&t=202&p=1147#p1147 and directly readjusted values from TM1 (1,78ms instead of 1,85 ms) and TM2 (1,19ms instead of 1,25ms) than noticed that tuning was almost ok. then, I trimmed by ear until it sounded the same as samples. Cowbell sounded ok for me before readjustment, but was actually better after that.
Well, I could have probably fixed that by replacing components, but this method did the job for me.
Maybe just try this or if you think the problem is somewhere else, then you should upload a few samples.
Hope this help.
Thanks Deepvibes,
I've spent a lot of time adjusting TM1 and TM2, but I'll try with the period you indicated.
I'll also upload samples.
I'll let you know the results.
I've spent a lot of time adjusting TM1 and TM2, but I'll try with the period you indicated.
I'll also upload samples.
I'll let you know the results.
Hi,
I've checked the TM1 and TM2 adjustments, it was quite good and and I readjusted precisely to 1.78ms and 1.19ms as indicated by DeepVibes. I've also checked the parts values around the U3 BP filter, as indicated by Vincent, and it was all correct.
But the problem is still there, bad sounding cymbal and hihat...
What I've found is that the others Scmitt trigger oscillators (which have fixed frequencies) are quite different from the theoritical frequencies of such oscillators (almost 10%). I think it's caused by the poor tolerance of the résistors. Does anyone knows if it can be the cause of the problem (incorret frequency of Scmitt trigger oscillators)?
Thank you,
Pat
I've checked the TM1 and TM2 adjustments, it was quite good and and I readjusted precisely to 1.78ms and 1.19ms as indicated by DeepVibes. I've also checked the parts values around the U3 BP filter, as indicated by Vincent, and it was all correct.
But the problem is still there, bad sounding cymbal and hihat...
What I've found is that the others Scmitt trigger oscillators (which have fixed frequencies) are quite different from the theoritical frequencies of such oscillators (almost 10%). I think it's caused by the poor tolerance of the résistors. Does anyone knows if it can be the cause of the problem (incorret frequency of Scmitt trigger oscillators)?
Thank you,
Pat
Hi,
I've finally found the problem, AOP U3 was bad... That's incredible, 2 bad ICs in a brand new kit (I had the counterfeit 4011 also)... That's a pity to sell kits with crap parts like that. Very bad for music DIY projects.
I've finally found the problem, AOP U3 was bad... That's incredible, 2 bad ICs in a brand new kit (I had the counterfeit 4011 also)... That's a pity to sell kits with crap parts like that. Very bad for music DIY projects.