DEAD Cocoquantus BUFFERS

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samule.edmoon
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DEAD Cocoquantus BUFFERS

Post by samule.edmoon » Sun Jun 14, 2020 8:56 pm

Hey everyone, I realize there’s a lot of threads out there regarding issues with the Cocoquantus but I’m looking for some help.

I’ve had my Cocoquantus 2 for 7-8 months now (bought new from Peter) and I think my buffers may have died. It worked fine when I first got it.

I picked up a Sidrax & a Plumbutter 2 shortly after (also bought new from Peter) and whenever I run them into the 1/8” stereo in on the front of the Coco, the delay buffers become super distorted no matter how I set the gain. It almost sounds like how they sound when you have the speed near it’s lowest setting, except it sounds like this with speed even at the highest setting. I’m aware that you need to clear the buffers first and all that but this almost sounds like they’re picking up noise no matter what, even after I clear them!

For the longest time, this was only happening with the other CL stuff, strangely enough. If I ran other synths in my studio or my phone into those inputs, I didn’t have any problems.

My studio does have pretty bad power thanks to an old house but I’ve tried running the Coco (& or all the other CL stuff) off 9v batteries and the problem still persists. I’ve checked with a handful of other users and they said they’re not having any issues when running Sid, Tet or Plum in. I also tried running them in via the banana out in mono and the issue is still there....

Today I ran my shared system into the 1/8” stereo in and got the same distorted noisy results from it. I’m kind of tired of powering it up and hoping it works, just to be continuously let down. Like I said, it worked fine when I first got it so I know how it should and can sound and this definately isn’t it (or anywhere near).

I emailed Peter a week ago but still haven’t got a response. I’ve also emailed him twice in the past and have never heard back from those either.

Does anyone have any recommendations on what I should do next? I love the Coco so much I’m considering buying another new one just to tie me over until the issue with this one gets resolved :doh:

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dogoftears
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Re: DEAD Cocoquantus BUFFERS

Post by dogoftears » Sun Jun 14, 2020 9:24 pm

stupid dumb question just in case, apologies ahead if this is so obvious as to be not worth mentioning:
did u unfreeze the buffers on power up? theyre always automatically on (indicated by the red led on each side) when you turn coco on, and produce a horrible noise. the two black buttons unfreeze them.
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Re: DEAD Cocoquantus BUFFERS

Post by samule.edmoon » Sun Jun 14, 2020 10:39 pm

dogoftears wrote:
Sun Jun 14, 2020 9:24 pm
stupid dumb question just in case, apologies ahead if this is so obvious as to be not worth mentioning:
did u unfreeze the buffers on power up? theyre always automatically on (indicated by the red led on each side) when you turn coco on, and produce a horrible noise. the two black buttons unfreeze them.
Oh yes, like I said I’ve had it awhile and it used to work fine!

That may have been an issue the very first time I tried it but it’s been a normal part of using it every since.
I do appreciate any input at all at this point though, so thank you regardless.

I can unfreeze the buffers, turn speed all the way up and feedback all the way down. I can even mute them and wait a few minutes. But as soon as there’s signal and I start to bring the feedback up, the noisy, distorted, ring moddy mess is always present :despair:

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Re: DEAD Cocoquantus BUFFERS

Post by k_bntzn » Mon Jun 15, 2020 2:52 am

Have you seen this thread? viewtopic.php?f=65&t=202455

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Re: DEAD Cocoquantus BUFFERS

Post by k_bntzn » Mon Jun 15, 2020 3:03 am

Why does not ciat lonbarde offer any guarantee on their products? How about patchpoint, do they offer any??

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Re: DEAD Cocoquantus BUFFERS

Post by samule.edmoon » Mon Jun 15, 2020 9:54 am

sungja wrote:
Mon Jun 15, 2020 2:52 am
Have you seen this thread? viewtopic.php?f=65&t=202455
I have! There’s at least one idea in there to try but I’ve tried almost everything and am pretty certain it’s done for!

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Re: DEAD Cocoquantus BUFFERS

Post by jimmie » Mon Jun 15, 2020 11:12 am

Is it noisy in 'delay mode' as well? Then definitely something's wrong I think. Try contacting Peter, he's usually responsive; maybe busy or something at the moment.

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Re: DEAD Cocoquantus BUFFERS

Post by trax » Mon Jun 15, 2020 11:18 am

Can you post a video of this? I would like to hear and see this on your COCO. Something is definitely going on with these coco's .....seems very similar to the issue I was having.

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Re: DEAD Cocoquantus BUFFERS

Post by samule.edmoon » Mon Jun 15, 2020 12:04 pm

trax wrote:
Mon Jun 15, 2020 11:18 am
Can you post a video of this? I would like to hear and see this on your COCO. Something is definitely going on with these coco's .....seems very similar to the issue I was having.
It is noisy in delay mode as well, maybe even worse :doh:

I’ll try and get a video in the next couple days! I’m super busy today but will def try if I can find the time.

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Re: DEAD Cocoquantus BUFFERS

Post by mrhoudis » Tue Jun 16, 2020 10:15 pm

You're sure there's enough gain on the signal? You're SURE? Like, gain before it hits the coco. Not gain from the buffer input knob.

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Re: DEAD Cocoquantus BUFFERS

Post by samule.edmoon » Wed Jun 17, 2020 12:28 am

mrhoudis wrote:
Tue Jun 16, 2020 10:15 pm
You're sure there's enough gain on the signal? You're SURE? Like, gain before it hits the coco. Not gain from the buffer input knob.
I think I’m sure?

Like I said initially I noticed it with Sidrax. I’m having the same issue with Tetrax now. I’ve tried all gain settings on Coco with no luck, same distorted buffers no matter what. Sometimes it seems like they freeze up or get locked in a loop too, no matter what the speed or feedback is at (even when we’ll below 12-11 O’clock). It doesn’t matter if I freeze the buffer or let them delay, the problem is there.

Strangely enough, I tried it again tonight with my easel and it worked pretty well for a little bit but then went back to being it’s finnicy self after a little while.

I realize that it’s an unpredictable piece and generally noisy but the first month I had it I recorded HOURS of music with my Minimoog as an input and had absolutely no issues what so ever, other than the little bit of noise that’s always gonna be there!

I’ve been in the same space too on the same power so I don’t think that’s the issue either. From the studies I’ve done trying to get a video to post here and show what’s going on, it seems that there’s noise permanently stuck in both the delays. With no input, I hardly have to turn the feedback knob up at all to hear it. It doesn’t matter how much I turn it on and off, ground it, how I power it, where I set the Dolby switches, how many times I clear the buffers or how long I keep speed at max and feedback at minimum. As soon as I turn the feedback up, it’s there. With or without input!

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Re: DEAD Cocoquantus BUFFERS

Post by k_bntzn » Wed Jun 17, 2020 12:53 am

samule.edmoon wrote:
Wed Jun 17, 2020 12:28 am
mrhoudis wrote:
Tue Jun 16, 2020 10:15 pm
You're sure there's enough gain on the signal? You're SURE? Like, gain before it hits the coco. Not gain from the buffer input knob.
I think I’m sure?

Like I said initially I noticed it with Sidrax. I’m having the same issue with Tetrax now. I’ve tried all gain settings on Coco with no luck, same distorted buffers no matter what. Sometimes it seems like they freeze up or get locked in a loop too, no matter what the speed or feedback is at (even when we’ll below 12-11 O’clock). It doesn’t matter if I freeze the buffer or let them delay, the problem is there.

Strangely enough, I tried it again tonight with my easel and it worked pretty well for a little bit but then went back to being it’s finnicy self after a little while.

I realize that it’s an unpredictable piece and generally noisy but the first month I had it I recorded HOURS of music with my Minimoog as an input and had absolutely no issues what so ever, other than the little bit of noise that’s always gonna be there!

I’ve been in the same space too on the same power so I don’t think that’s the issue either. From the studies I’ve done trying to get a video to post here and show what’s going on, it seems that there’s noise permanently stuck in both the delays. With no input, I hardly have to turn the feedback knob up at all to hear it. It doesn’t matter how much I turn it on and off, ground it, how I power it, where I set the Dolby switches, how many times I clear the buffers or how long I keep speed at max and feedback at minimum. As soon as I turn the feedback up, it’s there. With or without input!
Yeah this is the problem i think everyone talks about.

I have this on both delays on my cocolase and yesterday i took it apart and removed the opamps. Now i will use sockets and will report back with results when getting it all together again, hopefully next week.

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Re: DEAD Cocoquantus BUFFERS

Post by samule.edmoon » Wed Jun 17, 2020 1:20 am

I just tried my Tetrax again with a ton more gain and it certainly helped! It’s useable now at the very least, so I’m not as shit out of luck as I thought so I’d definately like to say thank you for that suggestion. Let’s see if I get this lucky tomorrow 😂

I look forward to hearing how your surgery goes though, I’d def love some more consistency & comfort 🤞

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Re: DEAD Cocoquantus BUFFERS

Post by mrhoudis » Wed Jun 17, 2020 8:30 am

I hate to sound like a dick but it’s honestly not THAT unpredictable, it just needs a ton of gain. It only seems unpredictable because you’re feeding it different things. The minimoog and easel probably sound good because they output hot signals. If you use the preamp on the left it’ll help boost the gain too, but the signal going into the buffer needs to be HOT. When you say the noise is there even when there’s no input signal, that’s because it’s amplifying and looping noise, so that’s to be expected. If there’s no signal it’s just going to try to boost silence, and when you boost silence you hear noise. When you turn it on there’s always going to be noise in the buffer that needs to be cleared, by turning speed all the way UP and turning feedback all the way DOWN, with record OFF (LED off). And if the feedback is turned up and it’s recording (LED on) with no signal, it’ll record noise, and that will need to be cleared. Actual electronic problems aren’t completely unheard of, I think there was one recently regarding a 5volt regulator, but in my very humble opinion the overwhelming majority of noise complaints on the forum are from people trying to use quiet signals, and other varieties of user error. I hope this helps.

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Re: DEAD Cocoquantus BUFFERS

Post by samule.edmoon » Wed Jun 17, 2020 9:50 am

mrhoudis wrote:
Wed Jun 17, 2020 8:30 am
I hate to sound like a dick but it’s honestly not THAT unpredictable, it just needs a ton of gain. It only seems unpredictable because you’re feeding it different things. The minimoog and easel probably sound good because they output hot signals. If you use the preamp on the left it’ll help boost the gain too, but the signal going into the buffer needs to be HOT. When you say the noise is there even when there’s no input signal, that’s because it’s amplifying and looping noise, so that’s to be expected. If there’s no signal it’s just going to try to boost silence, and when you boost silence you hear noise. When you turn it on there’s always going to be noise in the buffer that needs to be cleared, by turning speed all the way UP and turning feedback all the way DOWN, with record OFF (LED off). And if the feedback is turned up and it’s recording (LED on) with no signal, it’ll record noise, and that will need to be cleared. Actual electronic problems aren’t completely unheard of, I think there was one recently regarding a 5volt regulator, but in my very humble opinion the overwhelming majority of noise complaints on the forum are from people trying to use quiet signals, and other varieties of user error. I hope this helps.
It sure helped! And kind of explains why I was mostly having the issue with the “gentler” CL pieces.

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Re: DEAD Cocoquantus BUFFERS

Post by dksynth » Wed Jun 17, 2020 11:34 am

I have a coco here with a noisy buffer.... no matter what you do a rhythmic noise burst comes through if feedback loop is audible at all.

I tried a bunch of stuff but in the end what seems to work is a 100pf to GND right on the ADC input pin (TLC0820).

I’m going to do more testing but that might help someone if their issue is similar.

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Re: DEAD Cocoquantus BUFFERS

Post by mrhoudis » Wed Jun 17, 2020 2:58 pm

samule.edmoon wrote:
Wed Jun 17, 2020 9:50 am

It sure helped! And kind of explains why I was mostly having the issue with the “gentler” CL pieces.
Great, I’m glad! When I plug my Tetrax directly into the coco, I have to crank the input knobs all the way up to reduce the distortion. Same goes for the plumbutter.

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Re: DEAD Cocoquantus BUFFERS

Post by batchas » Thu Jun 18, 2020 12:34 pm

mrhoudis wrote:
Wed Jun 17, 2020 8:30 am
Actual electronic problems aren’t completely unheard of, I think there was one recently regarding a 5volt regulator, but in my very humble opinion the overwhelming majority of noise complaints on the forum are from people trying to use quiet signals, and other varieties of user error. I hope this helps.
It would help IMHO if you explain why it's happening only on one side of the Cocoquantus, while the other side is totally ok (I prefer to mention, we never know: using identical signals and settings of course).
Assuming that all users who mentioned having an "noise" issue are to blame is IMO not reasonable/rational, as you don't have their Cocoquantus, nor you don't know their experience with electronic gear.
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Re: DEAD Cocoquantus BUFFERS

Post by mrhoudis » Thu Jun 18, 2020 4:08 pm

batchas wrote:
Thu Jun 18, 2020 12:34 pm
mrhoudis wrote:
Wed Jun 17, 2020 8:30 am
Actual electronic problems aren’t completely unheard of, I think there was one recently regarding a 5volt regulator, but in my very humble opinion the overwhelming majority of noise complaints on the forum are from people trying to use quiet signals, and other varieties of user error. I hope this helps.
It would help IMHO if you explain why it's happening only on one side of the Cocoquantus, while the other side is totally ok (I prefer to mention, we never know: using identical signals and settings of course).
Assuming that all users who mentioned having an "noise" issue are to blame is IMO not reasonable/rational, as you don't have their Cocoquantus, nor you don't know their experience with electronic gear.
I’m sorry I exaggerated. I’m definitely not saying you’re to blame, I’m definitely not saying your cocoquantus doesn’t have electrical problems. And I’m definitely not saying all users. In the end the owner is the one listening to and playing it and they’re who knows what’s going on the best, definitely not me. I guess what I mean is it took me a long time to figure out why certain things sounded distorted and crunched. I know it’s a common thing, to plug things in and not know why it’s distorted. Using identical settings and signals for testing isn’t as intuitive for some people. If someone is asking “is mine broken” I think user error is can be a potential explanation until proven otherwise. I just want to make sure folks are positive their unit has an actual problem before they open it up and poke around. But if someone KNOWS theirs is broken, I won’t try to tell them otherwise.

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Re: DEAD Cocoquantus BUPFFERS

Post by trax » Thu Jun 18, 2020 4:27 pm

It’s strange because this question/issue has a loooooooong history here on muffs and on the FB “cool kids” group. (do a search for "Cocoquantus noise") It’s always described the same way and sometimes it’s on the left and sometimes on the right. You would think by now we would have a
definitive “ here is what is happening, and why this is happening....."

Over the years I have played enough of these things to know "all coco2’s are equal, but some coco2’s are more equal than others." :tu:

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Re: DEAD Cocoquantus BUFFERS

Post by batchas » Fri Jun 19, 2020 1:04 am

mrhoudis wrote:
Thu Jun 18, 2020 4:08 pm
I’m sorry I exaggerated. I’m definitely not saying you’re to blame, I’m definitely not saying your cocoquantus doesn’t have electrical problems. And I’m definitely not saying all users. In the end the owner is the one listening to and playing it and they’re who knows what’s going on the best, definitely not me. I guess what I mean is it took me a long time to figure out why certain things sounded distorted and crunched. I know it’s a common thing, to plug things in and not know why it’s distorted. Using identical settings and signals for testing isn’t as intuitive for some people. If someone is asking “is mine broken” I think user error is can be a potential explanation until proven otherwise. I just want to make sure folks are positive their unit has an actual problem before they open it up and poke around. But if someone KNOWS theirs is broken, I won’t try to tell them otherwise.
Makes sense :tu: :tu: :tu:
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Re: DEAD Cocoquantus BUPFFERS

Post by dksynth » Fri Jun 19, 2020 7:45 pm

trax wrote:
Thu Jun 18, 2020 4:27 pm
It’s strange because this question/issue has a loooooooong history here on muffs and on the FB “cool kids” group. (do a search for "Cocoquantus noise") It’s always described the same way and sometimes it’s on the left and sometimes on the right. You would think by now we would have a
definitive “ here is what is happening, and why this is happening....."

Over the years I have played enough of these things to know "all coco2’s are equal, but some coco2’s are more equal than others." :tu:
I've just posted a possible solution here, at least on the unit I have in here for repair extra capacitance added directly to the ADC input pin cures the buffer problems.

Symptoms were: non-clearable buffer, chugging noise that creeps in, no matter what you do the buffer slowly fills up with noise and garbage making live overdubbing and building melodies impossible.

I also added some gnd strapping across some areas as LEDs were affecting VCO frequencies in one section. Beefing up the GND helped.

If someone else has these issues I would love to know if this fix helped. I can submit photos if needed. There is a bypass cap right by the ADC with GND available right by the pin ... just drop a 0603 capacitor in there.

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Re: DEAD Cocoquantus BUPFFERS

Post by batchas » Sat Jun 20, 2020 12:36 am

dksynth wrote:
Fri Jun 19, 2020 7:45 pm
no matter what you do the buffer slowly fills up with noise and garbage making live overdubbing and building melodies impossible.
Exactly.
dksynth wrote:
Fri Jun 19, 2020 7:45 pm
If someone else has these issues I would love to know if this fix helped. I can submit photos if needed. There is a bypass cap right by the ADC with GND available right by the pin ... just drop a 0603 capacitor in there.
I'd like to have the details to try it, yes please :hail:
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Re: DEAD Cocoquantus BUFFERS

Post by k_bntzn » Sat Jun 20, 2020 6:59 am

I tried the cocolase feedback again with different chips. First i tried the tl064 but new ones, and surprisingly much better results. I have to turn feedback up to 12 clock before the crackling noises begin but now it is just a tiny bit just like the coco2 without dolbys up. I also tried lm324 and got even better results. Noise start again at same level but somehow more quiet. I dont know if this is the solution for all these issues regarding buffer noises but wanted to let you guys know there was improvement swapping opamps.

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Re: DEAD Cocoquantus BUPFFERS

Post by trax » Sat Jun 20, 2020 7:06 am

dksynth wrote:
Fri Jun 19, 2020 7:45 pm
trax wrote:
Thu Jun 18, 2020 4:27 pm
It’s strange because this question/issue has a loooooooong history here on muffs and on the FB “cool kids” group. (do a search for "Cocoquantus noise") It’s always described the same way and sometimes it’s on the left and sometimes on the right. You would think by now we would have a
definitive “ here is what is happening, and why this is happening....."

Over the years I have played enough of these things to know "all coco2’s are equal, but some coco2’s are more equal than others." :tu:
I've just posted a possible solution here, at least on the unit I have in here for repair extra capacitance added directly to the ADC input pin cures the buffer problems.

Symptoms were: non-clearable buffer, chugging noise that creeps in, no matter what you do the buffer slowly fills up with noise and garbage making live overdubbing and building melodies impossible.

I also added some gnd strapping across some areas as LEDs were affecting VCO frequencies in one section. Beefing up the GND helped.

If someone else has these issues I would love to know if this fix helped. I can submit photos if needed. There is a bypass cap right by the ADC with GND available right by the pin ... just drop a 0603 capacitor in there.

Posting photos would be great! I can do the work - but I am kinda not too smart at what I’m looking at. Thank you for this!

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