DIY Mutable Unsuccessful Builds

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DrenselQuad
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Re:

Post by DrenselQuad » Wed Mar 18, 2020 2:53 pm

JakoGreyshire wrote:
Sun Jun 09, 2019 7:01 pm
Altitude909 wrote:
JakoGreyshire wrote:I'm not having any luck loading Parasites into Twists... I will try to use different levels and computers etc... But Twists should be able to take parasites, right?




HybrisBehemoth yeah, your buttons are backwards.... see the little white dot on the eagle file? Underneath were it says SW4, and SW6... That is where the green dots line up with on the switch...


:tu:
Yes, I've verified that. Try a cell phone/tablet. Plancks is the only one that it doesnt work (for some unknown reason)
Okay, Yeah I tried Plancks after Twists... I bricked Planks and had to re-flash it with the command Terminal... Plancks is up and back to normal.. I was using my cell phone for Twists and Plancks but I got no indication from the Algo knobs... I even tried boosting the signal with Mutable Ears... No signal indication at all... Bummer that Plancks wont do it... I was looking forward to the euclidian mode on that... oh well....

Thanks Altitude909!!


It would maybe be nice if I could upload parasites as a Hex inside Vagrant instead of a .wav file...

I do you have any advice for me. I found myself in the same situation and am not sure how to reinstall the Stock firmware when the DAC/Receiver(?) keeps messing the install. Thanks.

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Faye
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Re: DIY Mutable Unsuccessful Builds

Post by Faye » Wed Mar 18, 2020 5:05 pm

cnicht wrote:
Wed Mar 18, 2020 4:31 am
One of the pads of C16 is GND so if you're measuring resistance to GND it will be zero, the other pad's measurement seems very low indicating a short or faulty component.

If no short is obvious you may need to start removing some of the active components until you find the fault.

It's a good idea to place the power supply components first and test for the power rails on the board. Then start placing the active components and measure as you go. There's a good guide here https://westlicht.github.io/performer/build/
Thanks a lot for your feedback. It seems that I'll have to learn this lesson the hard way. I will make sure to follow the guide that you posted on any future modules. Wish I had found such a guide earlier... :/

Meanwhile I spent countless hours trying to localize the problem.

I reflowed the pins on all active parts, but with no success.

@cnicht: you suggested removing one active part after another. how can I do the testing with this approach? this may be a dumb question, but is it save to power the module when a.e. some of the ICs or capacitors are removed?

Currently the following components are desoldered from the PCB for testing them:
- ceramic capacitors: C1, 2, 3, 55
- all electrolytic capacitors: C3, 4, 5, 7, 16, 22, 30

I also removed the following active parts:
- ICs: IC3, 5, 6

Previously I had mentioned that I measured almost zero resistance between the two pads of C16. This problem got solved when I removed IC5. Does this imply a fault with the IC5?

I also detected a cold solder joint on C21 which I fixed now. But I doubt that this was the source of my problems.

Also, I measured resistance on many of the capacitors on the PCB. Mainly on those in the STM32 and audio jack section of the schematics. I get a high resistance on almost all of them. The only exception are the following 3 capacitors, which are all connected to the tip signal of the jacks in the schematics. All of them show almost zero resistance when tested with the multimeter on the PCB:
(please note that IC 6 is not on the board at this moment.)

- C55 (connected to J1 tip signal)
- C58 (connected to J5 tip signal)
- C60 (connected to J8 tip signal)

I suppose that is not normal?
How do J1, J5 and J8 differ from the remaining jacks?

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Wed Mar 18, 2020 6:35 pm

If you replace IC3 are you getting the correct voltages across C3 and C22?

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Faye
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Re: DIY Mutable Unsuccessful Builds

Post by Faye » Thu Mar 19, 2020 6:06 pm

cnicht wrote:
Wed Mar 18, 2020 6:35 pm
If you replace IC3 are you getting the correct voltages across C3 and C22?
Ok, I think that I'm slowly getting the hang out of this.

As you suggested, I put IC3, C22 and C13 back on.

Here are the new findings:
- Now the LEDs are glowing. So I assume that at least with IC1 and IC2 everything is ok, right?

- And when I powered on the module the first time after putting IC3 back on, I measured 3.3V between pin1 and pin2, yay! Then I decided to replace some of the other capacitors that I had removed. I powered the module again and only measured 120mV between pin1 and pin2 of IC3. I removed those additional capacitors. So back to the state everything was when I had measured 3.3V. Strangely, I still measure 120mV. wtf?
Also, C13 gets quite hot. But somehow the buzzing noise is not present anymore. I suppose that is because most of the electrolytic capacitors are not on the PCB atm.

- I think I may have found the cause: I measure almost 0 ohm on the leads of the following capacitors: C19, C20, C22, C23, C24, C27, C28, C30, C36, C44 => all of these are connected to +3v3_A!!

- In addition, C23 + C24 are not only connected to +3v3_A, but also to the pins 24+25 of STM32. Those pins lie next to pin 23, which is the GND!! I tried to reflow the pins, and also had a close look under a microscope, but can't find any sign of shortage at all. I'm really reluctant to remove the STM32 (especially because I don't have any spare ones at hand), unless that would be really the next logical step. Is there anything else to check out, before I remove the STM32 maybe?

- Also, currently I removed the IC3 again, which provides the +3v3_A. Still, I measure 0ohm resistance between the pads for GND (pin2) and VO (pin1) on the PCB. Thus I conclude that the problem is not with IC3.

- C55, C58, C60: 0ohm resistance on these as well, but I don't see any connection to +3v3_A on these. Also, I don't see any other common signal for these three capacitors on the schematics...

A closeup pic of STM32. pins 23, 24, 25 are in the bottom right corner:
IMG_20200319_234501.jpg
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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Mar 20, 2020 3:27 am

There’s no reason why C13 should get hot unless it’s damaged.

The state of the LEDs will probably be random until the microcontroller is programmed.

There is probably as short(s) somewhere still on the board.

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Faye
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Re: DIY Mutable Unsuccessful Builds

Post by Faye » Fri Mar 20, 2020 9:23 am

Ok, good news! I was able to locate and solve the problem for the following capacitors: C19, C20, C22, C23, C24, C27, C28, C30, C36, C44.
It was a short on C22!
I'm happy that I didn't desolder the STM32.
I'm having a really hard time to solder these SMD electrolytic capacitors. Still havent found a good method with a normal soldering iron. The first pad is easy, but I can barely reach the second pad with the tip of the soldering iron once the first lead is soldered. And when I change to a finer tip, I can't conduct enough heat to the pad. I experience the same problem when soldering crystals btw. Would appreciate any advice for future projects.

Anyway, there is only one problem left at this time: 0ohm resistance on the capacitors C55, C58, C60 in the audio jack area. I unsoldered all of them and measured continuity on the pads directly. They still show 0ohm. I looked at the schematics, but I can't find any signal that these 3 capacitors have in common.

- C55 is connected to tip3 of J1
- C58 is connected to tip3 of J5
- C60 is connected to tip3 of J8
when I plug a cable into these jacks, the resistance of the corresponding capacitor changes from 0ohm to a very high resistance

Is this maybe intended by design and not a problem at all??

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Mar 20, 2020 11:01 am

The trick to desoldering the capacitors is to put more solder on their contacts so it forms a bulge.

Then apply the soldering iron at the side of the capacitor so that it heats both bulges simultaneously but not the body of the capacitor.

Push the capacitor to one side away from both pads whilst the solder is molten.

A hot air gun is a better solution.

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Mar 20, 2020 11:05 am

Some of the jack sockets are normalled to the normalisation probe so plugging in cables will change the measured resistance.

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Faye
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Re: DIY Mutable Unsuccessful Builds

Post by Faye » Fri Mar 20, 2020 5:16 pm

@cnicht ok, I finally got it working! thanks to your help!! :hail: :hail:
flashing the module was a piece of cake.

I think I've still got a long way to go though....before flashing, all LEDs were lit equally. now only the top green is lit strong enough. all other LEDs (including top one in red) are lit faintly (the bottom three are lit slightly better than the middle ones though). does this have to do with the LED driver IC2? Why did this issue pop up only after flashing?

Also, some of the sound modes sound kinda noisy/distorted, unlike the demo videos that I've watched on youtube. this mainly concerns the "red LED" sounds. does this have to do with the STM32? if the microcontroller has problems, why did I get a success message in the flashing software then?

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Mar 20, 2020 6:31 pm

Check you have the correct value components in place especially round the op amps

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Faye
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Re: DIY Mutable Unsuccessful Builds

Post by Faye » Sat Mar 21, 2020 7:44 am

Ok, I think further troubleshooting is pointless at the moment.

I resoldered IC5 and switched out C13 (the one that got hot as I had earlier reported), C1 and C2.
I switched the module on, but everything still the same: low LED light and distorted sound on some of the modes.
After a few minutes of wiggling around with the pots, now the output is dead too...lol

I decided to invest in a smart tweezer for further troubleshooting. Will hopefully report back in a few days when it arrives.

Thanks a lot for your help!

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extralifedisco
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Re: DIY Mutable Unsuccessful Builds

Post by extralifedisco » Sat Mar 21, 2020 6:08 pm

hndmrsh wrote:
Wed Mar 18, 2020 2:20 am
Sooo I guess I jumped the gun a little bit... it's basically perfectly working, other than the fact it still shuts down randomly after being on for some time :bang:. I'm not sure if it would be heat-related, because if I turn my system off and then immediately back on again, it runs for a while again before shutting down. Seems to last about 10 or 15 minutes each time... although maybe if I turn the system off and and on, it doesn't last quite as long the next time? Hard to say for sure, I haven't timed it. Does anyone have any ideas what might be causing this? I'll probably just try to reflow a bunch of components again until it (hopefully) works permanently, but if anyone has any ideas about what the root cause could be, that would be very useful!
That's pretty mystifying. It could be a leaky electrolytic capacitor - they should have basically infinite resistance, but if they're old or they've been overheated sometimes they don't. This can cause higher current draw than expected, overheat resistors, lower expected voltages. Have you measured the current draw on both rails and compared to spec?

If you want a quick and dirty test, power it up and wait until it shuts down. Then connect a lead to the PCB ground (alligator clip works nicely), and touch the other end to each capacitor's pads. If grounding one of them causes it to reset and turn back on, that cap is probably bad.

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aseaman
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Re: DIY Mutable Unsuccessful Builds

Post by aseaman » Sat Mar 21, 2020 6:16 pm

I was finally able to loop back up on troubleshooting my Plaits module.

Since last time, I inspected the various components around the DAC and noticed that the capacitors for C29 and C31 were actually oriented incorrectly -- they were vertical rather than horizontal. I've since placed them correctly and reflowed the pins of the DAC as well as all of the other components in that vicinity. Below are the various voltage readings I'm getting for the DAC -- it looks like the charge pump is still not working correctly based on the values for pins 2, 4, and 5.

Code: Select all

Pin 1 - 3.293			Pin 11 - 3.302
Pin 2 - 0.3mV			Pin 12 - GND
Pin 3 - GND			Pin 13 - 1.601
Pin 4 - 195.2mV			Pin 14 - 1.630
Pin 5 - 0.50			Pin 15 - 0.787
Pin 6 - 3.4mV			Pin 16 - GND
Pin 7 - 3.5mV			Pin 17 - 3.302
Pin 8 - 3.293			Pin 18 - 1.887
Pin 9 - GND			Pin 19 - GND
Pin 10 - GND			Pin 20 - 3.293

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HybrisBehemoth
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Re: DIY Mutable Unsuccessful Builds

Post by HybrisBehemoth » Sun Mar 22, 2020 2:14 am

I have been troubleshooting a Branches module for a while now. The lower Bernoulli Gate works fine. But the upper one doesn't give any output and the LED is constantly on (green) regardless of there being an input or not.
The input signal seems to stop at transistor Q1 (MMBT3904). Q1 is correctly connected to ground and gets input when I send a gate (0.55v, which is a bit lower that the corresponding transistor in the working circuit, Q2, which gets 0.6v). Q1, however gives no output (which Q2 does). So I desoldered and switched out Q1... twice. But I still get the same result.

So; third time's the charm? Or am I missing something?

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Sun Mar 22, 2020 7:31 am

@aseaman

Are these AC or DC measurements?

Do you have an oscilloscope to measure signals with?

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aseaman
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Re: DIY Mutable Unsuccessful Builds

Post by aseaman » Sun Mar 22, 2020 11:31 am

The measurements were all DC and I just recently got a scope however I'm still learning the ins and outs of it.

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hndmrsh
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Re: DIY Mutable Unsuccessful Builds

Post by hndmrsh » Tue Mar 24, 2020 2:35 am

extralifedisco wrote:
Sat Mar 21, 2020 6:08 pm
hndmrsh wrote:
Wed Mar 18, 2020 2:20 am
Sooo I guess I jumped the gun a little bit... it's basically perfectly working, other than the fact it still shuts down randomly after being on for some time :bang:. I'm not sure if it would be heat-related, because if I turn my system off and then immediately back on again, it runs for a while again before shutting down. Seems to last about 10 or 15 minutes each time... although maybe if I turn the system off and and on, it doesn't last quite as long the next time? Hard to say for sure, I haven't timed it. Does anyone have any ideas what might be causing this? I'll probably just try to reflow a bunch of components again until it (hopefully) works permanently, but if anyone has any ideas about what the root cause could be, that would be very useful!
That's pretty mystifying. It could be a leaky electrolytic capacitor - they should have basically infinite resistance, but if they're old or they've been overheated sometimes they don't. This can cause higher current draw than expected, overheat resistors, lower expected voltages. Have you measured the current draw on both rails and compared to spec?

If you want a quick and dirty test, power it up and wait until it shuts down. Then connect a lead to the PCB ground (alligator clip works nicely), and touch the other end to each capacitor's pads. If grounding one of them causes it to reset and turn back on, that cap is probably bad.
Thanks for these suggestions, I'll definitely do some of these tests soon! I was going to buy a new multimeter, but my country's now gone into full lockdown for the next 4 weeks, so that might take a little while longer now!

Interestingly, I was just building a patch (which didn't use the Rings), and noticed after 45 minutes the Rings still hadn't shut down. I was curious to see what would happen if I tried to use it, so I plugged a square pulse into the strum input, and as soon as the pulse went high... sure enough, it shut down immediately! Not sure if that gives you any more clues as to what the cause could be... :hmm:

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gamblid
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Re: DIY Mutable Unsuccessful Builds

Post by gamblid » Tue Mar 24, 2020 11:40 pm

Don't know if anyone could help me with this. I've been trying to fix my clouds for quite a while now... So recently i was reading and somebody mentioned that if you programmed clouds with a 5v ftdi it could kill your processor. I went and replaced mine with a new one because the ftdi i had was 5v. So today i programmed the new processor but my clouds still sounds like shit.

Symptoms: Knobs barely modify anything in the sound, it lags like hell (takes like 3 seconds to modify the dry signal), pitch knob barely does anything after you've turned it 10% (just goes intantly up pitch or low, theres no middle ground), and in general it sound like shit.

The only thing i know is: MCP6002 and MCP6004 is giving 3.3V on VDD an 0V on VSS, TL072's are giving -12 and +12 on their V- and V+.
wm8731s is giving 3.3v on its VDD. Im suspicious of the WM chip, but i was suspicious of everything else so i don't know anymore.

Another thing to note is that my FTDI voltage was 3.38v. Don't know if that could affect anything? I have tried running it through jtag but no dice either, it just doesn't want program with it.

demo of the bad sound


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gamblid
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Re: DIY Mutable Unsuccessful Builds

Post by gamblid » Wed Mar 25, 2020 12:33 pm

Making another small post. I noticed something, can programming the clouds with a 5V ftdi kill the wm8731s audio codec chip?

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akashic53
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Re: DIY Mutable Unsuccessful Builds

Post by akashic53 » Wed Mar 25, 2020 1:31 pm

bonzai wrote:
Tue Mar 17, 2020 3:27 pm

But when I power off my case and power it on again, the "Steps" pot seems to have no function at all anymore, i only get octave jumps as it sounds, regardless of the Steps position. Checked all solder joints, re-flowed almost everything around the Steps pot, but no luck.
Now I've just found out that when I then redo calibration step 3, it works again until the next power cycle.

Any ideas? Did I brick my STM or is it something more trivial?

Cheers,
bonzai
I have just been troubleshooting a similar problem on Cara where the STEPS pot did not function and the module only produced octaves. The cause was incorrect voltage at pin7 of ic6, which is part of the STEPS CV input, due to a cold solder joint. Try reflowing ic6.
If you suspect an MCU internal issue, you could dump the calibration data at 0x08004000 - 0x08008000. The calibration data is actually in the first 64 bytes of that, followed by the quantization data. Use a hex editor to decode the floating point numbers and verify.

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Re: DIY Mutable Unsuccessful Builds

Post by auditorycanvas » Fri Mar 27, 2020 3:45 am

Hi everyone, I'm looking for a bit of help/advice.

I recently bought an assembled Blinds clone module. It seemed to work great for CV, but when I used it for Audio, I noticed the the sound was distorted/clipping. This seems to happen before the attenuator/knob stage, as even a fraction past 12, and the sound is distorted. Turning it up doesn't increase the distortion/clipping, it just amplifies the distorted/clipped sound.

It's the same across all 4 inputs and outputs, and any combination of them. This is with one channel (any channel), and all other channels and knobs set at 12 (or close to it where the level is actually zero. I've tried with the output of a Rings module, a 1010 Bitbox, and any other input fed into it, same result.

I've tried different cables, power strip, different case and power supply, all to try and rule things out, but so far no dice. the issue persists. It basically sounds like you'd expect when something doesn't have enough headroom and starts to distort/clip. All modules I tried running into it don't clip/distort when bypassing Blinds and going straight into a mixer or other device, so it's not that whatever I'm feeding it is too hot.

The seller isn't being very helpful so far, so if it comes to the worst, I'm looking at either repairing it, or writing it off as a bad experience.

If anyone has an idea what might be causing this, and where I might start trying to fault find, I'd greatly appreciate it. I'm not terrible with a soldering iron, also have a hot air station (relatively cheap one), but my electronics knowledge is quite minimal, i.e. basic repairs of obvious/visible faults, or with guidance, and a number of kit builds, including eurorack modules (Rings, Elements, and a few Snythro kits).

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akashic53
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Re: DIY Mutable Unsuccessful Builds

Post by akashic53 » Fri Mar 27, 2020 12:59 pm

Blinds is not too complicated - just a bunch of opamps. Since it is a global problem, I would check the +/- supply voltages at the opamp supply pins. Take a look at the board for obvious faults. See if there are any hot components.

bonzai
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Re: DIY Mutable Unsuccessful Builds

Post by bonzai » Fri Mar 27, 2020 1:37 pm

Hi again,

Still no luck here, I don't get Cara to keep its calibration data. I just swapped out the STM32 for a brand new one, and even did the whole re-calibration procedure from scratch, but no luck. Same effect as before: right after feeding the 1V/3V in step 3, everything works, but after a power cycle or chip reset, it stops working and I need to do step 3 over and over again. :bang:

What could be the issue here? I am completely lost now...

Cheers,
bonzai
bonzai wrote:
Tue Mar 17, 2020 3:27 pm
Hey guys,

I could need some help: a while ago, I've built an Antumbra Cara (Marbles clone). So far, it works somewhat correctly, but every time I power cycle the module, it seems to lose its calibration data.
I've followed all three calibration steps from the usual pdf: measured voltages, patched settings.cc, re-compiled and re-uploaded the patched firmware (marbles_bootloader_combo.hex, I am using the Segger J-Link mini via JTAG connector btw) and calibrated the rate/steps with 1 and 3 V from my BSP.
Right after this, the module works just fine, when turning the "Steps" pot, I am getting a quantized sequence. Brilliant.
But when I power off my case and power it on again, the "Steps" pot seems to have no function at all anymore, i only get octave jumps as it sounds, regardless of the Steps position. Checked all solder joints, re-flowed almost everything around the Steps pot, but no luck.
Now I've just found out that when I then redo calibration step 3, it works again until the next power cycle.

Any ideas? Did I brick my STM or is it something more trivial?

Cheers,
bonzai

bonzai
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Re: DIY Mutable Unsuccessful Builds

Post by bonzai » Sat Mar 28, 2020 11:15 am

Hi akashic53! (sorry, did not see your last post yesterday)

I'ts alive!!! :yay:
Didn't touch the solder joints (I did that yesterday once again without any luck), but what I did different now was I put all pots at 12h position, all modes to green (mainly to get just the cal difference in the dump and not any other stuff like button status or so), calibrated, did a "good" memdump, reset the chip (that's were things went wrong last time), did another memdump and guess what! Now it suddenly works! No difference in the dumps either. Very strange... :eek: :hmm:

Thanks for the hint! :)

Cheers,
bonzai

Edit: oops, too early - went bonkers again after some hours of noodling. Seems you were right with the solder joints...
akashic53 wrote:
Wed Mar 25, 2020 1:31 pm
bonzai wrote:
Tue Mar 17, 2020 3:27 pm

But when I power off my case and power it on again, the "Steps" pot seems to have no function at all anymore, i only get octave jumps as it sounds, regardless of the Steps position. Checked all solder joints, re-flowed almost everything around the Steps pot, but no luck.
Now I've just found out that when I then redo calibration step 3, it works again until the next power cycle.

Any ideas? Did I brick my STM or is it something more trivial?

Cheers,
bonzai
I have just been troubleshooting a similar problem on Cara where the STEPS pot did not function and the module only produced octaves. The cause was incorrect voltage at pin7 of ic6, which is part of the STEPS CV input, due to a cold solder joint. Try reflowing ic6.
If you suspect an MCU internal issue, you could dump the calibration data at 0x08004000 - 0x08008000. The calibration data is actually in the first 64 bytes of that, followed by the quantization data. Use a hex editor to decode the floating point numbers and verify.
Last edited by bonzai on Sun Mar 29, 2020 7:42 am, edited 1 time in total.

bman
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Re: DIY Mutable Unsuccessful Builds

Post by bman » Sat Mar 28, 2020 6:43 pm

I'm troubleshooting an Antumbra Knit (Plaits clone) that's been puzzling me for a while.

Everything works but the output volume on both outs is too low. As long as I run it through a VCA to bump up the level, everything sounds great. But if I don't it's super quiet compared to my Elements or Braids. Also the level also seems to rise a little in the first ~10-15 seconds I've got it powered on. So it starts almost silent, then rises up to a level that's audible but nowhere near the level of my other modules.

My initial thought is that since it's a problem with BOTH outputs, it's got to be something to do with the TL072. I replaced the TL072 as well as all of the resistors and capacitors immediately connected to it. Based on the Eagle file, I checked continuity from each pin on the TL072 to each point it should be connected to and that seems fine. Also made sure none of the pins are connected (except the two that are connected to ground). Made sure the TL072 is getting +12V and -12V.

Any ideas of what else might be causing both outputs to be low volume?

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