a legend is back...System-700 in eurorack

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wendallsan
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Re: a legend is back...System-700 in eurorack

Post by wendallsan » Tue Apr 14, 2020 11:06 am

+1 to Pharmasonic for authenticity! I had not even noticed the misspelling in the 1st place, much less done the research to 'appreciate' the misspelling. :sb:
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Re: a legend is back...System-700 in eurorack

Post by gslug » Sun Jun 07, 2020 8:32 pm

Well after a long delay, I've finally put two cases together and started ordering parts for the modules. Finding the BOM a bit of a PITA as it isn't exactly specific regarding things that have to physically fit, i.e. pots and switches. Also having trouble finding knobs that look the part - can I ask what you used wendallsan?
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wendallsan
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Re: a legend is back...System-700 in eurorack

Post by wendallsan » Mon Jun 08, 2020 9:41 am

gslug wrote:
Sun Jun 07, 2020 8:32 pm
Well after a long delay, I've finally put two cases together and started ordering parts for the modules. Finding the BOM a bit of a PITA as it isn't exactly specific regarding things that have to physically fit, i.e. pots and switches. Also having trouble finding knobs that look the part - can I ask what you used wendallsan?
I used 'synth pointer knobs' as sold by Thonk:

https://www.thonk.co.uk/shop/synth-pointer-knobs/

There are many other suppliers of these types of knobs, though, so check the stock of whomever you're ordering your other parts from and they may have them. The BOM's for the SYS-700 modules were the 1st I had ever read, so I didn't know any better. Some of the boards are a little wacky, especially the LFO's with their crazy rotary switch wiring.
Currently building a whole mess of modules by Nonlinear Circuits. Troubleshooting a Nonlinear Circuits Sauce of Unce.

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Re: a legend is back...System-700 in eurorack

Post by gslug » Mon Jun 08, 2020 10:18 am

wendallsan wrote:
Mon Jun 08, 2020 9:41 am
I used 'synth pointer knobs' as sold by Thonk:

https://www.thonk.co.uk/shop/synth-pointer-knobs/

There are many other suppliers of these types of knobs, though, so check the stock of whomever you're ordering your other parts from and they may have them. The BOM's for the SYS-700 modules were the 1st I had ever read, so I didn't know any better. Some of the boards are a little wacky, especially the LFO's with their crazy rotary switch wiring.
Thanks! I didn't think of looking at Thonk, despite getting the jacks from them.

I haven't looked at the LFOs yet... Just soldered the Multiples as I already had the parts, and ordered parts for the VCOs.
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Re: a legend is back...System-700 in eurorack

Post by gslug » Tue Jun 09, 2020 11:28 am

Progress:
IMG_20200609_143615.jpg
I have a roll of tolex, but that can wait.
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Re: a legend is back...System-700 in eurorack

Post by wendallsan » Tue Jun 09, 2020 12:18 pm

Excellent! As a self-builder of my own cases for this project, I applaud your progress! :sb:

I'm no pro with tolex yet, but it's not that hard to do with adequate spray glue and superglue for any stubborn corners.

I managed to hide most of my worst mistakes with corner brackets, etc. :miley:
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Re: a legend is back...System-700 in eurorack

Post by gslug » Tue Jun 09, 2020 7:06 pm

wendallsan wrote:
Tue Jun 09, 2020 12:18 pm
Excellent! As a self-builder of my own cases for this project, I applaud your progress! :sb:

I'm no pro with tolex yet, but it's not that hard to do with adequate spray glue and superglue for any stubborn corners.

I managed to hide most of my worst mistakes with corner brackets, etc. :miley:
Thanks! This is the first woodwork I've done since school, and that wasn't this century... I might try tolexing a few offcuts and see how it goes.
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Re: a legend is back...System-700 in eurorack

Post by gslug » Sun Jun 21, 2020 6:56 am

Finally, some modules!
IMG_20200621_114834.jpg
3 702 VCOs built. Not calibrated yet, and I need to work out why one if them appears to be totally dead.
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Re: a legend is back...System-700 in eurorack

Post by gslug » Wed Jul 01, 2020 4:18 pm

The dead VCO had a short between two pins on the SMT transistor array. Now fixed.

Building a few more modules:
IMG_20200629_125842.jpg
Still have't got around to attempting the Tolex, but the first case is starting to look like a synth:
IMG_20200701_202448.jpg
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Re: a legend is back...System-700 in eurorack

Post by 3vcos » Wed Sep 09, 2020 10:19 pm

I'm guessing that sequencer is a dead hope.

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Re: a legend is back...System-700 in eurorack

Post by LektroiD » Fri Nov 20, 2020 2:58 am

3vcos wrote:
Wed Sep 09, 2020 10:19 pm
I'm guessing that sequencer is a dead hope.
I was just on the Pharmasonic site, looks like the sequencer has been pulled, and no sign of the 715 filter either.

Has anyone received any other orders from Pharmasonic recently? I'm a little reluctant to make any orders just now if everything is halted.

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Re: a legend is back...System-700 in eurorack

Post by KSS » Fri Nov 20, 2020 3:28 am

Pretty sure Synthcube picked these up. Should be safe to get them there.

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Re: a legend is back...System-700 in eurorack

Post by wendallsan » Fri Nov 20, 2020 11:07 am

I've sent sent a request over a month ago to them to refund my pre-orders for the sequencer and have not heard back, so I would be cautious. Ordering from a 3rd party such as SynthCube sounds like a good idea to me. FWIW, I'm guessing that the Behringer System 100 modules wouldn't be too far off from these functionally, other than the obvious differences in size and design style. I do really like the look and the layout of Pharmasonic's modules after having worked with some very 'densly packed' modules. Hard to get your fingers around those knobs to tweak them when they're crammed so close together! Hopefully Pharma pulls through for us all, I know these are rough times for lots of us.
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Re: a legend is back...System-700 in eurorack

Post by LektroiD » Mon Nov 23, 2020 5:52 am

Looks like Synthcube only have kits, which is ok for beginners who don't have a stock of parts, but like most I prefer to buy PCB/Panel sets as I have a good stock of parts and can't justify spending 5 times the price to buy parts I've already invested in. Besides I'm in the uk, so I'd have shipping and import duty on top. I'd be better off buying pre-made Behringer's and saving myself the hassle. Just a shame my Sys-700 cabinet will never be finished.

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Re: a legend is back...System-700 in eurorack

Post by MuadMusic » Thu Dec 03, 2020 9:42 am

LektroiD wrote:
Fri Nov 20, 2020 2:58 am
3vcos wrote:
Wed Sep 09, 2020 10:19 pm
I'm guessing that sequencer is a dead hope.
I was just on the Pharmasonic site, looks like the sequencer has been pulled, and no sign of the 715 filter either.

Has anyone received any other orders from Pharmasonic recently? I'm a little reluctant to make any orders just now if everything is halted.
I ordered from Pharmasonic back in March. The Covid shut down airmail because airmail piggy backs on commercial air traffic (passenger flights). It was not until September that Japan to US mail service resumed. When it did resume, it resumed via Sea (not Air). My package was promptly sent by Pharmasonic 9/3/20. It cleared customs 9/10/20. It arrived 11/24/20 in Birmingham, AL.

Ori was good about communications throughout the long wait. I would not hesitate to order from Pharmasonic again but count on a wait, until air traffic picks back up.

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Re: a legend is back...System-700 in eurorack

Post by DisappearHere » Tue Dec 22, 2020 1:41 am

I wonder if anyone else has had a similar problem and could help me troubleshoot my 703F VCF build.
It takes power without issue and there's no magic smoke. If I turn up the resonance all the way it appears to self-oscillate, as the top LED lights up (and I can control this with CV into the resonance input. However nothing appears on the output, including the self-resonance of the VCF or any input.

Does anyone have any suggestions on where to look for faults?

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Re: a legend is back...System-700 in eurorack

Post by diode_destroyer » Thu Dec 24, 2020 9:15 pm

DisappearHere wrote:
Tue Dec 22, 2020 1:41 am
I wonder if anyone else has had a similar problem and could help me troubleshoot my 703F VCF build.
It takes power without issue and there's no magic smoke. If I turn up the resonance all the way it appears to self-oscillate, as the top LED lights up (and I can control this with CV into the resonance input. However nothing appears on the output, including the self-resonance of the VCF or any input.

Does anyone have any suggestions on where to look for faults?
Do you have an oscope? If so, you can trace through and check the signal at the output stage of each of the opamps after each CA3080 stage (see schematic here: http://www.florian-anwander.de/roland_s ... 03e_a3.jpg ). Assuming all solder joints and component values/locations are fine, most likely issue could be a bad CA3080 (or opamp, or transistor).

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Re: a legend is back...System-700 in eurorack

Post by MuadMusic » Thu Dec 31, 2020 3:38 pm

OK, this is DOTCOM format (not euro) but I've put together the following in the System-700 series
Mult

Analog Switch (2 video part)


and gate delay (works, but no video yet).

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Re: a legend is back...System-700 in eurorack

Post by DisappearHere » Fri Jan 01, 2021 10:29 am

diode_destroyer wrote:
Thu Dec 24, 2020 9:15 pm
DisappearHere wrote:
Tue Dec 22, 2020 1:41 am
I wonder if anyone else has had a similar problem and could help me troubleshoot my 703F VCF build.
It takes power without issue and there's no magic smoke. If I turn up the resonance all the way it appears to self-oscillate, as the top LED lights up (and I can control this with CV into the resonance input. However nothing appears on the output, including the self-resonance of the VCF or any input.

Does anyone have any suggestions on where to look for faults?
Do you have an oscope? If so, you can trace through and check the signal at the output stage of each of the opamps after each CA3080 stage (see schematic here: http://www.florian-anwander.de/roland_s ... 03e_a3.jpg ). Assuming all solder joints and component values/locations are fine, most likely issue could be a bad CA3080 (or opamp, or transistor).
Thanks for pointing me in the right direction. I was able to trace a signal to the CA3080s and the opamps and all seemed to be OK. In the process of doing this I revisited my choice not to place the 10uF capacitor marked NP on the board. I referred back to the mouser cart associated with the BOM (as the BOM itself also marks this capacitor as NP), and discovered that rather than indicating "Not populated" or "Do not place" in fact seems to indicate "Non-polar" meaning a bipolar capacitor has to be placed. After adding the capacitor the filter works as expected. An unfortunate case of user error/misinterpretation, but thank you, as you helped me work out where I went wrong!

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Re: a legend is back...System-700 in eurorack

Post by diode_destroyer » Fri Jan 01, 2021 8:39 pm

DisappearHere wrote:
Fri Jan 01, 2021 10:29 am

Thanks for pointing me in the right direction. I was able to trace a signal to the CA3080s and the opamps and all seemed to be OK. In the process of doing this I revisited my choice not to place the 10uF capacitor marked NP on the board. I referred back to the mouser cart associated with the BOM (as the BOM itself also marks this capacitor as NP), and discovered that rather than indicating "Not populated" or "Do not place" in fact seems to indicate "Non-polar" meaning a bipolar capacitor has to be placed. After adding the capacitor the filter works as expected. An unfortunate case of user error/misinterpretation, but thank you, as you helped me work out where I went wrong!
Awesome...glad you got if figured out! I am actually currently trying to figure out why the Pharmasonic Digisound LP VCF I just built isn't acting like a low-pass filter... good times.

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Re: a legend is back...System-700 in eurorack

Post by ndkent » Fri Jan 01, 2021 10:51 pm

There won't be much/anything unpopulated in the Pharmasonic 700 pcbs. I've been inside 70s Roland, they used a fair amount of bipolar electros.
diode_destroyer wrote:
Fri Jan 01, 2021 8:39 pm
Awesome...glad you got if figured out! I am actually currently trying to figure out why the Pharmasonic Digisound LP VCF I just built isn't acting like a low-pass filter... good times.
Digisound filters have tricky boms and unpopulated parts. I found the original 80s build doc useful but the euro has different resistors. Anyway there is a thread here viewtopic.php?f=17&t=197467&hilit=digisound
Last edited by ndkent on Tue Jan 12, 2021 5:33 am, edited 1 time in total.

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Re: a legend is back...System-700 in eurorack

Post by diode_destroyer » Mon Jan 11, 2021 7:00 pm

ndkent wrote:
Fri Jan 01, 2021 10:51 pm
Digisound filters have tricky boms and unpopulated parts. I found the original 80s build doc useful but the euro has different resistors. Anyway there is a thread here viewtopic.php?f=17&t=197467&hilit=digisound
Yes. I am a dumb dumb and had installed R33, which one should not do for the low pass. Cut it out and all is well now!

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Re: a legend is back...System-700 in eurorack

Post by KSS » Tue Jan 12, 2021 5:30 am

@diode_destroyer
Congrats! Gotta love it when a plan comes together.

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