My build log - MidTom not working, and more..

Hello,

I have encountered some problems with my Nava.

Ive finished my build a few days ago, the kit are from the last batch, and with parts from the latest mouser bom.

From the beginning, almost everything worked properly except:

1. MIDTOM sometimes it sounds metallic almost like a HI-HAT, or as a very high pitched TOM, this problem varies between the two 'errors', depending on if I press down on the vr14. …wrong pot, or defective?? edit. pot is ok

2. CLAP, works but it has too high volume out. ...wrong pot, or defective?

Now, after a few hours of testing, a couple of other parts is not working properly: (but they did from start..)

* LCD, it's lit but shows no letters, sometimes I see 'blocks' on the top line but still no letters visible. (TM2 has stable 5V)

* HI-HAT, Sounds like it does not have the correct sample rate, it sounds chopped up...

* MASTER VOLUME, Worked well from the start but now almost nothing happens when you turn it up / down. (IIRC from the beginning the sound from main out got distorted when it was pushed over 50/60% volume but now its not.)...wrong pot, or defective?

Has anyone experienced any of these problems? Grateful for all the help I can get.

Cheers!!

the hi-hat issue, a faulty "blue" chip..

Itchy wrote: 1. MIDTOM sometimes it sounds metallic almost like a HI-HAT, or as a very high pitched TOM, this problem varies between the two 'errors', depending on if I press down on the vr14. …wrong pot, or defective?? edit. pot is ok

I had problems with mid tom and VR14, too.
mayber this helps:
viewtopic.php?f=24&t=832&start=40#p4781

check if the metal standof off the pot is touching the via (tiny hole in the PCB) right below it.

regarding clap - have you followed the calibration of the clap with the trim pot?

comboy wrote:
Itchy wrote: 1. MIDTOM sometimes it sounds metallic almost like a HI-HAT, or as a very high pitched TOM, this problem varies between the two 'errors', depending on if I press down on the vr14. …wrong pot, or defective?? edit. pot is ok
I had problems with mid tom and VR14, too.
mayber this helps:
viewtopic.php?f=24&t=832&start=40#p4781

check if the metal standof off the pot is touching the via (tiny hole in the PCB) right below it.

regarding clap - have you followed the calibration of the clap with the trim pot?

I desoldered vr14, and now when its back in place again it no longer has the shorting problem.. however the metallic sound is still there, tune and decay works but the sound is wrong.

CLAP... no I haven't done that properly yet so ill just leave that for now. there are still some other problems to be solved. But I'm pretty sure that it has to do with the calibration as you pointed out. thanks!

Your clap is ok, if you want less just lower the volume knob on the front panel ... In addition to a TR909 can not lower the accent directly for the clap, there is only one pad, on the keyboard for the clap and that is accent is highter.(I have not started to build my Nava, but i guess it's like on a TR909) The trimmer has nothing to do with the volume, it's for noise clap.
Your tom, i had this problem in the past on my 9090. Strange metalic sound..

It was just a dry weld.

Dr.Knob wrote:Your clap is ok, if you want less just lower the volume knob on the front panel ... In addition to a TR909 can not lower the accent directly for the clap, there is only one pad, on the keyboard for the clap and that is accent is highter.(I have not started to build my Nava, but i guess it's like on a TR909) The trimmer has nothing to do with the volume, it's for noise clap.
Your tom, i had this problem in the past on my 9090. Strange metalic sound.. It was just a dry weld.

Yes, clap is ok.

MidTom, checked all solder points but no obvious fault, transistors all seems to be ok, replaced ic22 but I think I overheated the pcb because it looks like at least one of the solder points has come off for IC22..and now its no sound at all.. :/ so I went on and bought a desolder gun..I will now try to rebuild the whole section.and repair pcb :/

Itchy wrote:
Dr.Knob wrote:Your clap is ok, if you want less just lower the volume knob on the front panel ... In addition to a TR909 can not lower the accent directly for the clap, there is only one pad, on the keyboard for the clap and that is accent is highter.(I have not started to build my Nava, but i guess it's like on a TR909) The trimmer has nothing to do with the volume, it's for noise clap.
Your tom, i had this problem in the past on my 9090. Strange metalic sound.. It was just a dry weld.

Yes, clap is ok.

MidTom, checked all solder points but no obvious fault, transistors all seems to be ok, replaced ic22 but I think I overheated the pcb because it looks like at least one of the solder points has come off for IC22..and now its no sound at all.. :/ so I went on and bought a desolder gun..I will now try to rebuild the whole section.and repair pcb :/

before you do any reworking check the continuity of the pcb with the schematic as if as suggested Dr.Knob had this problem with dry solder and you reflowed all then it may be a broken trace. It would then probably make sense at least to test for this before digging into rebuilding

dinsync wrote:
Itchy wrote:
Dr.Knob wrote:Your clap is ok, if you want less just lower the volume knob on the front panel ... In addition to a TR909 can not lower the accent directly for the clap, there is only one pad, on the keyboard for the clap and that is accent is highter.(I have not started to build my Nava, but i guess it's like on a TR909) The trimmer has nothing to do with the volume, it's for noise clap.
Your tom, i had this problem in the past on my 9090. Strange metalic sound.. It was just a dry weld.

Yes, clap is ok.

MidTom, checked all solder points but no obvious fault, transistors all seems to be ok, replaced ic22 but I think I overheated the pcb because it looks like at least one of the solder points has come off for IC22..and now its no sound at all.. :/ so I went on and bought a desolder gun..I will now try to rebuild the whole section.and repair pcb :/
before you do any reworking check the continuity of the pcb with the schematic as if as suggested Dr.Knob had this problem with dry solder and you reflowed all then it may be a broken trace. It would then probably make sense at least to test for this before digging into rebuilding

thank you dr.knob and dinsync! =)

Have gone over all points and re-heated them.. Well now it's probably time to check the continuity of the pcb..

The next challenge is to get life back in HiHat section, it's working but sounds terrible, something wrong with the sample rate?. Probably the is error in EEPROM, thing is that it worked from the beginning, before the I did the "Init EEPROM mode".

Itchy wrote:
comboy wrote:
Itchy wrote: 1. MIDTOM sometimes it sounds metallic almost like a HI-HAT, or as a very high pitched TOM, this problem varies between the two 'errors', depending on if I press down on the vr14. …wrong pot, or defective?? edit. pot is ok
I had problems with mid tom and VR14, too.
mayber this helps:
viewtopic.php?f=24&t=832&start=40#p4781

check if the metal standof off the pot is touching the via (tiny hole in the PCB) right below it.

regarding clap - have you followed the calibration of the clap with the trim pot?

I desoldered vr14, and now when its back in place again it no longer has the shorting problem.. however the metallic sound is still there, tune and decay works but the sound is wrong.

CLAP... no I haven't done that properly yet so ill just leave that for now. there are still some other problems to be solved. But I'm pretty sure that it has to do with the calibration as you pointed out. thanks!

I'm having the same problem on the new PCB...

OR?