uJOVE, micro version of JUVE multimode filter

Cwejman, Livewire, TipTop Audio, Doepfer etc... Get your euro on!

Moderators: lisa, luketeaford, Kent, Joe.

User avatar
neonmercury1
Wiggling with Experience
Posts: 349
Joined: Tue Jan 10, 2017 11:15 pm
Location: Berlin

Post by neonmercury1 » Thu Apr 11, 2019 2:17 pm

Silver wrote:Anyone have a mouser cart set up for this? Thanks
i just placed a mouser order and im pretty sure its all correct and there but of course it would be best to check and make sure. but here is the mouser project.

https://www.mouser.com/ProjectManager/P ... 71683d176d

moogah
Wiggling with Experience
Posts: 444
Joined: Mon Nov 22, 2010 10:27 am

Post by moogah » Thu Apr 11, 2019 2:22 pm

cackland wrote:Analog circuit with digital filter selection?
BOM shows DG409 and CD4052 multiplexers in there, so I'd guess this is the same or similar technique as on the original JP6.

User avatar
cackland
Super Deluxe Wiggler
Posts: 2019
Joined: Thu Dec 28, 2017 5:42 pm
Location: Los Angeles, California

Post by cackland » Thu Apr 11, 2019 3:04 pm

moogah wrote:
cackland wrote:Analog circuit with digital filter selection?
BOM shows DG409 and CD4052 multiplexers in there, so I'd guess this is the same or similar technique as on the original JP6.
Roger.. should have checked the BOM :eek:

User avatar
Silver
Common Wiggler
Posts: 212
Joined: Mon May 02, 2016 5:02 pm
Location: New York

Post by Silver » Thu Apr 11, 2019 3:15 pm

neonmercury1 wrote:
Silver wrote:Anyone have a mouser cart set up for this? Thanks
i just placed a mouser order and im pretty sure its all correct and there but of course it would be best to check and make sure. but here is the mouser project.

https://www.mouser.com/ProjectManager/P ... 71683d176d
Thanks!

User avatar
neonmercury1
Wiggling with Experience
Posts: 349
Joined: Tue Jan 10, 2017 11:15 pm
Location: Berlin

Post by neonmercury1 » Thu Apr 11, 2019 4:56 pm

Silver wrote:
neonmercury1 wrote:
Silver wrote:Anyone have a mouser cart set up for this? Thanks
i just placed a mouser order and im pretty sure its all correct and there but of course it would be best to check and make sure. but here is the mouser project.

https://www.mouser.com/ProjectManager/P ... 71683d176d
Thanks!
yeah i just made it yesterday because i couldnt find one and was going to post it when i saw you asked for it today so it was perfect timing. please let me know if you find any errors seeing that i just ordered yesterday.

vafu
Learning to Wiggle
Posts: 3
Joined: Wed Jun 26, 2019 4:57 am
Location: Ukraine

High frequency bleed

Post by vafu » Wed Jun 26, 2019 5:25 am

Just finished mine, and with all modes I can hear noticeable amount of high frequencies passing through even with fully closed filter.
Where can I start looking for a problem ?
Maybe I just messed with some resistor values...

mrerdat
Common Wiggler
Posts: 176
Joined: Fri Mar 31, 2017 4:38 pm

Post by mrerdat » Wed Jun 26, 2019 9:52 am

I have a pair of uJoves and experience the same bleed with highs leaking through with a fully closed filter. Just a guess, but maybe this has to do with the feedback modification being hard wired into the circuit.

I might one of these days cut the feedback PCB trace to find out...

User avatar
Prunesquallor
Veteran Wiggler
Posts: 533
Joined: Wed Nov 11, 2009 3:08 am
Location: Valencia, Spain

Post by Prunesquallor » Wed Jun 26, 2019 12:41 pm

Not 2 hp? Fail! :haha:
If at first you don't succeed read the instruction manual.

User avatar
necrobious
Common Wiggler
Posts: 166
Joined: Wed Aug 20, 2014 2:26 pm
Location: Portland

Post by necrobious » Wed Jun 26, 2019 12:59 pm

mrerdat wrote:I have a pair of uJoves and experience the same bleed with highs leaking through with a fully closed filter. Just a guess, but maybe this has to do with the feedback modification being hard wired into the circuit.

I might one of these days cut the feedback PCB trace to find out...
I have three uJoves i built up a few months back, never noticed bleed (admittedly, my hearing isnt what it used to be). Does the bleeding show up on an oscilloscope?

mrerdat
Common Wiggler
Posts: 176
Joined: Fri Mar 31, 2017 4:38 pm

Post by mrerdat » Wed Jun 26, 2019 1:28 pm

I don't have an oscilloscope to test but it's mainly audible when you have a really quiet patch with the filter closed all the way. It's not a huge problem when other stuff is happening in the same patch (drums, other voices, etc)

It's like there's a very quiet (maybe -20dB or so) partially filtered copy of the signal bleeding through. This is a problem if you are using the LPF modes to mute the signal completely because a little bit of leakage is still audible.

I'll cut the trace on one and report back. It'll be easy to repair if I want to undo it. If I wanted feedback after the trace is cut I can always just recreate that signal path by patching.

mrerdat
Common Wiggler
Posts: 176
Joined: Fri Mar 31, 2017 4:38 pm

Post by mrerdat » Wed Jun 26, 2019 5:07 pm

Well just bypassed the feedback circuit- cut two traces and soldered the output TL074 pin directly to R2 and.....

I was wrong! Even with the feedback path disabled the slight bleed is still there and is coming from somewhere else.

vafu
Learning to Wiggle
Posts: 3
Joined: Wed Jun 26, 2019 4:57 am
Location: Ukraine

Post by vafu » Thu Jun 27, 2019 5:33 am

mrerdat wrote:Well just bypassed the feedback circuit- cut two traces and soldered the output TL074 pin directly to R2 and.....

I was wrong! Even with the feedback path disabled the slight bleed is still there and is coming from somewhere else.
From my investigations, there is something wrong near Pin 1 of IC1 (TL074).
If detach it and listen/oscilloscope separately for both pad and leg, no bleed noticed there, IC outputs filtered audio, (but weirdly crackles on low cutoff) and on pad there is quiet copy of filtered audio.
But once you solder pin&pad together, on lowest cutoff, it bleeds (both pin1 and output)
I’m not experienced enough to go further, so any help would be highly appreciated!

vafu
Learning to Wiggle
Posts: 3
Joined: Wed Jun 26, 2019 4:57 am
Location: Ukraine

Post by vafu » Thu Jun 27, 2019 5:38 am

necrobious wrote:
mrerdat wrote:I have a pair of uJoves and experience the same bleed with highs leaking through with a fully closed filter. Just a guess, but maybe this has to do with the feedback modification being hard wired into the circuit.

I might one of these days cut the feedback PCB trace to find out...
I have three uJoves i built up a few months back, never noticed bleed (admittedly, my hearing isnt what it used to be). Does the bleeding show up on an oscilloscope?
It’s visible on scope, yes.
It’s really noticeable by ear only on high pitched waves with rich harmonics, try pure square

User avatar
ym2612
Super Deluxe Wiggler
Posts: 1099
Joined: Mon Feb 24, 2014 8:54 am
Location: Brooklyn, NY

Post by ym2612 » Fri Jun 28, 2019 3:18 pm

Finished building mine last night. It's bliss. It's replacing a DIY Ripples, which is... fine? Just overly polite, without as wide a palette.

I didn't use the specified LED. I used a common-cathode RGB LED from Mouser, which has a different pinout, so the colors won't match up with the manual, but it's fine. I changed R71 to 10k to get the red brightness to match the green and blue.

zoth4355
Learning to Wiggle
Posts: 2
Joined: Sun Oct 26, 2014 10:23 am

uJove bleeding issue

Post by zoth4355 » Fri Jul 26, 2019 1:22 pm

Love my uJove, but I'm also getting that bleed in all modes, more noticeable in some, less in others. Tried various calibration settings by ear, haven't solved the issue. Still useable but would be nice to cut into that unwanted noise.

I'll recheck the pcb and do some reflow later today. In the meantime, any pointers?

Thanks

User avatar
necrobious
Common Wiggler
Posts: 166
Joined: Wed Aug 20, 2014 2:26 pm
Location: Portland

Post by necrobious » Mon Jul 29, 2019 10:59 pm

I had a chance to test all three of mine using a 9.9k square wave from a z3000, and couldn't hear any bleed. My scope is in a fixed location in my home that is apart from where my rack is, making connecting them difficult. I am unable to look at the uJoves output under the scope at the moment but will try next time I can move the scope or the rack.
Not sure if it helps, but I do recall calibrating the resonance response to be a bit softer than what was recommended in the instructions.

lacuna
Learning to Wiggle
Posts: 17
Joined: Fri Aug 18, 2017 6:32 am

Post by lacuna » Wed Aug 07, 2019 10:36 am

are there any news on this?

is this a problem with the dense PCB layout per se, as bleed often is?
how did you guys solder? with airflow? clean?
What PSU and power-bus do you use?
People with bleed and those of you without?

I am just guessing and
i am thinking about building one ...

User avatar
necrobious
Common Wiggler
Posts: 166
Joined: Wed Aug 20, 2014 2:26 pm
Location: Portland

Post by necrobious » Wed Aug 07, 2019 11:06 am

lacuna wrote:are there any news on this?

is this a problem with the dense PCB layout per se, as bleed often is?
how did you guys solder? with airflow? clean?
What PSU and power-bus do you use?
People with bleed and those of you without?

I am just guessing and
i am thinking about building one ...
I hand solder mine using a fine tip on a temp controlled iron ($100 Weller iron) under a microscope. I clean up excess solder on a joint with braid. I probably put on more flux that is needed, but only because I've messed up builds by being stingy with flux in the past. After I get passives and ICs on the board, I use isopropyl alcohol and an old soft bristle toothbrush to clean the board gently, then dab dry, and letting it air dry over night usually. After that, I do the pots, jacks switches, LEDs, and panel install.

I also do continuity testing on ICs when I'm installing them, since they are usually a finer pitch, and I want to make sure I got a good contact to the board, and do not have a short with a neighboring pin.

My process is not quick nor perfect, but I'm building modules for myself and for the love of building, so I don't mind taking my time.. and even then, I still make mistakes occasionally.

Gidra
Learning to Wiggle
Posts: 35
Joined: Sun May 23, 2010 2:26 am

Post by Gidra » Mon Aug 12, 2019 9:08 am

For the ones who have the bleed has anyone managed to fix it?

User avatar
Shayshez
Learning to Wiggle
Posts: 36
Joined: Wed Aug 30, 2017 10:06 am
Location: Israel

Post by Shayshez » Mon Aug 12, 2019 6:08 pm

Hi,
Today I found the cause of the problem
The problem is caused by crosstalk between the input amp to the output amp shared in IC1.
I will update the PCB files to new version with separate op amps and try to create instructions to fix old pcbs.

User avatar
Shayshez
Learning to Wiggle
Posts: 36
Joined: Wed Aug 30, 2017 10:06 am
Location: Israel

Post by Shayshez » Fri Aug 16, 2019 12:08 pm

I did a small board with place for separate output op amp, next week I will test it and write mod guide (should take 10 minuts to assemble).

I will upload the fix board files to my Github together with updated PCB files of uJove (v1.2).
as usual you will be able to order those boards from Pusherman.

Image
Image

User avatar
selfdestroyer
Wiggling with Experience
Posts: 261
Joined: Wed Jun 18, 2014 3:42 pm
Location: Fresno, CA USA
Contact:

Post by selfdestroyer » Fri Aug 16, 2019 10:13 pm

Awesome, thanks Shayshez for the efforts and update.
My DIY / Music Blog They Remain Silent

User avatar
Shayshez
Learning to Wiggle
Posts: 36
Joined: Wed Aug 30, 2017 10:06 am
Location: Israel

Post by Shayshez » Sat Aug 31, 2019 4:39 am

fix method for the bleeding issue is confirmed.
The FIX board will be available soon at Pusherman, also new version of uJove board (v1.2) without this problem will be available after i will confirm it during next week.

Installation video:


I want to thank the members of this wonderful forum who pointed out the problem and allowed me to improve this module.


Image

mrerdat
Common Wiggler
Posts: 176
Joined: Fri Mar 31, 2017 4:38 pm

Post by mrerdat » Sun Sep 01, 2019 8:40 pm

Thank you for this fix!

Gidra
Learning to Wiggle
Posts: 35
Joined: Sun May 23, 2010 2:26 am

Post by Gidra » Tue Sep 03, 2019 11:25 am

Yea thanks alot for the fix , grea8 support :sb:

Post Reply

Return to “Eurorack Modules”