e-licktronic Forum

Hi. I was going to split this into 2 posts but thought it would be best as there is a lot of relative findings and problems.

First of all I started with a 1.1 build from last year and wanted to update the accent with the mux boards. I also had extra mux boards to build for v1.2 (5 sets in total) I plan to build so thought to build all together and ensure they are good and working in my v1.1. straight away I had faults. The env3 fault discussed by klang was there on all mux boards, a fault at env2 of the snare, also faults with the digital parts and also the rim and clap (these are common at IC111). My first thought was that it was probably bad soldering technique and I had maybe killed an ic or 2 but then I found I had one set which was working well. its good to note for first time builders that using tap mode bypasses the crash and ride accent circuit so you can check that your circuits work.

This is how it sounds. bad follows good

next I started to take some measurements from the good working set and drawing up a schematic working out which ic and its pin outs are related to each instrument during this time I managed to kill my one good set so next was to order spares of all the parts and better tolerance caps. straight away I managed to get the good set up and running again by just swapping out ic3 .

My confidence grew from this and this is when I entered the mux rabbit hole......

I started changing out ic's and caps on another set which had a bad ride, rim and clap (all on ic111) first was ic's 3 and 4 and straight away there was a difference. Good ride and both the analogue parts were good, but the crash was now dead. to cut a long story short I've been going around in circles with various mux boards and it seems is almost impossible to get a good working ride AND crash (except for my one good pair). The analogue parts have no problems and even though the crash and ride sound bad you can hear the global accent working on the part.

After realising there is no way (I believe) of making the accent work with certain mux boards on the digital section I went to work on the main board concentrating on the envelope part of the crash and accent in. I was pulling resistors and fitting a pot and turning hoping to find a sweet spot sometimes this got close but was never correct, this also effected how the accent would work a lot of the time. Also changing the voltage of TM2 improved the sound and also raising the resistance value of R697 but still this was not correct.

regarding the snare fault I found there to be a pitch bend fault on env2. this was resolved by copying the env3 mod, I havent scoped anything yet but to my ear it sounds correct, this fault was audible on both the v1.1 and v1.2.

last but by no means least on my v1.2 build the master output is a bit crunchy at full volume and accented notes, I'm yet to start fault finding this one yet so it could be a parts placement/value issue.

what else can be tried im wherry to start moding the mainboard circuits and really wondering if there might be a mux board mod which might make thing work better.

Hi serum114,

Did you update with the last firmware ?
Did you rewrite pattern step cause on last firmware the accent value isn't the same ?

Did you manage to get your Navas working before the

Yes. All is correct, the recording is of my 1.2 just with different mux. All instruments work as expected in tap mode but there is something wrong with the mux board. I have managed to make 2 boards work (out of 10) at ic111 after hours of work. Seems strange how its only an effect on the 2 of the 3 digital parts and both are releted to just the global accent. Strange how sensitive they are. I can have a good working ride change ic4 to try fix the crash but then end up with either both not working or just the crash. Seems that some boards just wont work. Interference maybe? Strange that you can hear the accent working but have a bad digital part. How is this related?

I’ve noticed the same issue, I’ve built multiple MUX pcbs and always an issue with crash or ride.

Thanks druu.

So you haven't overcome this problem and its a case of building them until one works correctly at ic111?

Vincent.. Yesterday was again spent pulling ics and caps from mux boards and still I wasn't able to get another good working mux. I even pulled every component and replaced and still it sounds as before. Where is my fault?? Remember I do have 2 boards that work correctly at ic111.

serum114 wrote: So you haven't overcome this problem and its a case of building them until one works correctly at ic111?

I have mine mostly working but my cymbals (CH/OH, Ride, Crash) still don’t sound as good as running without the MUX populated, mostly the decay is affected.

I would gladly run without the MUX boards but then global accent doesn’t work and also the signal becomes too ‘hot’ and somewhat distorted. I may try removing the MUX and repopulating the missing caps from each section to see if that helps. All of the MUX pcbs I’ve built were assembled meticulously so I’m not sure what the issue is either. Maybe still firmware related?

With the current MUX I have installed, the sounds are perfect when using TRIG-1, only they sound different through the sequencer (cymbals only!).

I'm not sure it will help. I replaced the caps for the cymbals on my v1.1 and it still sounded bad with my dodgy mux boards.

serum114 wrote:I'm not sure it will help. I replaced the caps for the cymbals on my v1.1 and it still sounded bad with my dodgy mux boards.

Oh I meant revert to the circuit pre-MUX. So use 4051's in place on IC111 and IC114 and populate the caps in each voice (e.g. C89 BD cap, etc). Along with this maybe revert to v1.023 firmware.. If I get the sound I'm after with that then I won't bother with the MUX pcbs..

So you are on an earlier board than v1.2?

serum114 wrote:So you are on an earlier board than v1.2?

If you mean v1.02, I’m on that version. Adding the caps would be a mod for me as they were removed from this revision.