Nava V1.02 Build Issues - Missing 7 Drum Voices !

Hi, I’ve just finished building my first Nava (v1.02) and I’m looking for some troubleshooting advice.
I have sample playback on Ride, Crash and Hats but no other voices are working.
I've done the initialise EEPROM to start and adjusted to 5V on TM2 but haven't adjusted TM1 yet. Also on V1.024 firmware.

I can hear some output on the VCO’s - though the snare sounds very strange - and all ‘drum’ voices exhibit very long decay when listening to the VCO’s. Also no output at the Envelope, but I guess that’s to be expected. Also no output on the Handclap, and Rimshot is very quiet.

I’ve read some people have had issues with M5218L chips, which I’m really hoping I don’t have to replace them, as there are 36 of them on the board !

The codes on mine are mostly “ 1602 ” though some are “ 1Z18 “

Otherwise, the volume of the crash is ridiculously loud compared to the hi-hats - which I think are the only thing working ‘correctly’ at this point.
All triggers seem to be working, and I think accents are also fine.

There’s some ground noise and digital (sounds like CPU processing) noises at the main output, which change pitch or mute with various button combinations. I’m guessing this is due to broken voices.

Any advice on the above would be very helpful! Really hoping to get this up and running properly soon,
Thanks!

First things first, upgrade to 1.026, then troubleshoot.

viewtopic.php?f=25&t=864#p4853

You should try listening in on the mainbiard using a pair of headphones by touching the tip on the output connection (where the 4 pin molex connect) and grounding the the sleeve. This should determine if its the instrument circuit or an issue with either wiring or the master. I've built 4 1.2 boards with the same batches of ml218s and found only about 5 bad opamps. All my transistors have been good. If it seems to be a fault in the instrument circuit check your polirized parts orientation and for bad soldering. If your instruments seem ok check your wiring is good and your master output. Keep a clear head and be maticuless, work on one sound at a time, the rimshot is the simplest circuit and then the kick. If you have a scope check you are getting triggers to trig and accent.

Also out of 4 builds i found 3 bad an6912 in the clap circuit. It may be worth ordering one these worked well for me if you are in europe/uk Look at this on eBay http://www.ebay.co.uk/itm/162684890279

Upgraded to 1.026 firmware and found the source of the problem - a bad ground connection on the sequencer Molex connection.

All seems to be working pretty well, but the clap with has no attack, just the tail of the sound. Is this likely due to the AN6912 IC?

All seems to be working pretty well, but the clap with has no attack, just the tail of the sound. Is this likely due to the AN6912 IC?

Yes. You could email Vincent to get you a replacement but depending on where you are it'll most likely be quicker to order something more local.