#413

just completed the build and i’m seeing that moving the fader for 1-4 will send midi for both 1-5, 2-6, 3-7, 4-8 and the fader for 13-16 will send for two faders in the same manner (but reversed so 9-13 at the same time). any thoughts on what to reflow? i’m thinking maybe i messed up some of the diodes? happy to take pics if that helps.

#414

Does anyone know if there’s a newer build guide for the sweet sixteen Mk ii? I have a suspicion that this one is actually for the mk i.

https://www.tesseractmodular.com/manuals/sweet-sixteen-manual#h.p_fvRYt1YCD0pW

#415

reflowing the resistor clusters helped! need to sort out one of the faders jumping values.

#416

aaaaand reflowing the mux and one of the other op amps got it working!

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#417

After a few corrections my build seemed functional, but next day fader 16 showed an issue I have been unable to fix so far, on the USB MIDI part: it goes the whole way but instead of running from 0 to 127 now runs from 78 to 127… where should I look?

Update: it was on the fader itself. All good now, thanks again for everything!

#418

Well in all cases it won’t be 14 bit definition as the faders go from 0 to 8192, so 13 bit max, 12 most likely as the whole range can hardly be exploited. Still would be interesting to try and see how that would work.

#419
Summary

I just got my 16n on my i2c bus and I’m seeing some oddities with the fader readings. Is this a calibration issue?

Updated to v2. In the tester I saw some noise occurring. It appears an old quirk of my build is back. :man_facepalming:t2:

Okay, so, I have continued to experience a ton of oddities with specifically one fader. I have tried basically everything to fix this: Swapping resistors, reflowing the chip and more. I cannot seem to figure this out…

Basically, when Fader 4 is at zero, it will occasionally show a midi value of 76. If I move Fader 1 or 2, that value can fluctuate wildly. But, if I put my finger down and put pressure on chip U1, that value can drop to zero…

If the fader is in the bottom minimum position and I wiggle it a litte, the value will jump all over, leading me to believe this is a fader issue, not a soldering issue…

If I move the slider, it will appear to function correctly. It is odd. I have all of these basic issues with it where I begin to think that maybe it is the fader itself. Are there any troubleshooting tips some might suggest?

EDIT: Worth putting here, my issue with fader 4 was a cold solder. My issue with the TT readings was not having done the fader calibration.

#420

I‘m about to order the components and was wondering if there‘s a reason not to take these cheaper jacks:

https://www.mouser.de/ProductDetail/CUI-Devices/MJ-3536N?qs=WyjlAZoYn51vdgS3Tq1ykQ%3D%3D

Instead of these:

https://www.mouser.de/ProductDetail/CUI-Devices/MJ-3536?qs=WyjlAZoYn51x8ZESutVK6g%3D%3D

Only difference I can see is that the cheaper ones don‘t have a thread which won’t be needed for the faderbank build.

16n is a bank of faders [release thread]
#421

Order from thonk and they’re cheaper yet

PJ302M

These may fit better than the CUI ones

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#422

I‘m ordering from mouser anyway. So I won‘t be cheaper if I have to pay the extra shipping costs for a thonk order…(don‘t need anything else from thonk)

Edit: oh better fitting is an argument

1 Like
#423

I think the lack of threads might be the key difference given the product numbers.

I think the PJ302M is a clone of the CUI jack, so the fit should be similar, but can’t remember for sure.

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#424

Tayda have them too. Listed as PJ-302M 3.5mm Mono Phone Jack.

I used them for my 16n. Also used in Cha/v video synth and Mystic circuits 0hp builds.

https://www.taydaelectronics.com/catalogsearch/result/?q=PJ-302M+3.5mm+Mono+Phone+Jack

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#425

So I’m having some similar issues with the reading of some of the connections. Most of the channels range from 0-110 (and seem normal), channel 5 only goes to 78, and channels 8,9 and 12 don’t register at all.

Based on my lack of SMD soldering skills I would think that I need to reflow some of the resistors and probably the capacitors, but I want to trace down the path.

How can I view the circuit diagram to see what connections to check for each of the fader channels? Like which of the resistors is related to each of the channels?

Edit: it looks like encoder 9 is actually W8 on the schematic is this right?

image

Thanks!

#426

Hi everyone - apologies if this has been requested/discussed above, but wondering whether it’s possible to configure/scale CV outputs arbitrarily? I’m imagining something like the lovely midi scaling feature in ableton live.

This would make it possible to keep modulation within the needed parameter, and also give you the full fader throw.

#427

I believe the cv ports are hardwired. There is no software control.

1 Like
#428

This is correct, the cv outs are direct voltage divisions coming from the fader circuit.

#429

I just populated a board and I think there is maybe a short somewhere, but I’m not sure how to troubleshoot it. I can connect via the web interface and adjust the Fader Minimum/Maximum calibration settings to get it from 127 down to 0, but zero happens at about 40% up, and if I bring the slider down lower than that it jumps back up to 127. If one is at 0, and I bring another one down, then 0 jumps up to 96. Not sure where to start trying to figure it out soldering wise or if it is just something to fix in code? Any help would be appreciated.

16n is a bank of faders [release thread]
#430

The troubleshooting guide in the 16n github has you covered for these kind of issues. Take a look. It’s likely that you just need to reflow a few joints.

Specifically this

Move each fader up and down for its full travel on its own. You should see a bar smoothly rise above the number of that channel for the full ‘height’ of the box (you’ll see). Hopefully, this will all work correctly. If it doesn’t, here are some possible catches:

nothing moves: check the fader pins; check carefully that the opamps are all the right way around and every pin is connected to its pad (and only its pad). Check carefully that the mux is the right way around and every pin on the mux are connected.
a bar doesn't move nearly far enough; this means the voltage is being divided too much. Check the resistors at the op-amp for that channel (each op-amp handles two channels, left-to-right); one might not be connected or soldered correctly.
beyond a certain point of travel, all the bars move up; this means that too much voltage is flooding into the mux. Again, check the resistors on the op-amp related to that channel - for instance, if channel 14 is causing this problem, check the resistors on the right of the seventh op-amp (U8)

From here https://github.com/16n-faderbank/16n/wiki/Build-guide

2 Likes
#431

Yep. This is the voltage divider resistors for the opamp channels in question, as mentioned in the build guide, and in many occasions in this thread.:point_up:

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#432

It is all the channels though, so I guess it is the multiplexer?

I reflowed everything and looked at everything with my magnifiers, and can’t see anything that is off.

It was a board of pre-populated surface mount components, from Emitum, so I guess I’ll check with them.