[AVAILABLE] Pharmasonic Series 700 synthCube kits

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[AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by synthcube » Wed Aug 19, 2020 10:09 am

We are pleased to announce availability of full synthCube kits for the Pharmasonic eurorack DIY modules...

First to be released is available now -- the full kit for the 702 VCO.

The 704 VCA kits are available as of August 2020.

This thread can be used for documentation, build questions, examples, etc.
synthCube kit BOMs are attached here for reference original BOM and build notes are available via the Pharmasonic website


enjoy!!

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707-large_default.jpg
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Attachments
703F synthCube Kit BOM.pdf
(137.41 KiB) Downloaded 9 times
SYS-700 schematics.zip
(566.45 KiB) Downloaded 13 times
723 synthCube Kit BOM.pdf
(757.05 KiB) Downloaded 8 times
704 synthCUbe Kit BOM.pdf
(800.76 KiB) Downloaded 17 times
Pharmasonic 702 VCO Synthcube Kit BOM.pdf
(142.75 KiB) Downloaded 13 times
Last edited by synthcube on Sat Oct 31, 2020 1:50 pm, edited 5 times in total.
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Re: [AVAILABLE] Pharmasonic 702 VCO synthCube kits

Post by pfzzz » Thu Aug 20, 2020 8:43 am

this link is dead: "music from outer space euro smt: www.mfoseuro.com"
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Re: [AVAILABLE] Pharmasonic 702 VCO synthCube kits

Post by synthcube » Thu Aug 20, 2020 8:45 am

pfzzz wrote:
Thu Aug 20, 2020 8:43 am
this link is dead: "music from outer space euro smt: www.mfoseuro.com"
thank you, yes, we are working on updating that site at the moment and adding more content and products-- back up soon-- thanks!
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Re: [AVAILABLE] Pharmasonic 702 VCO synthCube kits

Post by ndkent » Thu Aug 20, 2020 9:02 am

p.s. Lorlin CK1060 isn't on your BOM

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Re: [AVAILABLE] Pharmasonic 702 VCO synthCube kits

Post by synthcube » Thu Aug 20, 2020 9:12 am

ndkent wrote:
Thu Aug 20, 2020 9:02 am
p.s. Lorlin CK1060 isn't on your BOM

thank you :)
Its in the kit, we will amend the BOM
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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by appliancide » Sun Sep 13, 2020 1:05 pm

I'm comparing a few notes with synthcube and Pharmasonic before I post my full build report. Is there anything people want to hear from this oscillator? Specific patches? I suppose the most interesting things with a given VCO are its sync behavior and how it responds to modulation, so that's what I will try to focus on, but I'm happy to attempt any suggestions.

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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by ndkent » Sun Sep 13, 2020 3:48 pm

appliancide wrote:
Sun Sep 13, 2020 1:05 pm
I'm comparing a few notes with synthcube and Pharmasonic before I post my full build report. Is there anything people want to hear from this oscillator? Specific patches? I suppose the most interesting things with a given VCO are its sync behavior and how it responds to modulation, so that's what I will try to focus on, but I'm happy to attempt any suggestions.
On my build I'm hearing sync at work but not sure if it's properly working.
Not hearing a strong and weak difference atm.
At a higher external frequency I hear and see shape distortion. At a lower I hear locking to harmonics. Strong and weak sound the same

So to me it would be worth hearing.

Strong Sync, changing external frequency higher
Weak Sync, changing external frequency higher
Strong Sync, changing external frequency lower
Weak Sync, changing external frequency lower

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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by appliancide » Mon Sep 14, 2020 7:04 pm

Build report

Image
Image
They are recycling baggies now! That's pretty cool, as we all know how wasteful that part of this hobby can be.
Image


First, some potential gotchas and helpful (hopefully) clarifications:

1. This one is under investigation by synthcube and Pharmasonic, but it looks like certain LM301 chips will not work for the square output circuit (IC10). The beta kit had 3 National Semiconductor LM301AN comparator chips. They worked fine in two of the positions, but not IC10. As soon as one side of the zener reference is lifted, you get a rail-to-rail square wave, so the compensation pins (or at least pin 8) do not work correctly on these chips. I had an old LM301 in my parts bin, and as soon as I swapped it in, the square out worked as designed (positive only). What needs to be determined is if the natsemi parts in question are not 100%, yet somehow made it into the wholesale market, or if the natsemi parts just won't work. The natsemi datasheet uses pretty much the exact circuit as this VCO as one of the application examples.

Just think about how long synthcube have been providing us with tested rare parts, in addition to dealing with discrepancies in different manufacturers' versions of supposedly "standard" parts. It really makes you appreciate the service that they offer!

2. Like many panels these days, this module has a PCB faceplate. Mine had a bit of a curve to it.
Image
I just had to use extra care when lining up and soldering in the panel parts. I bent the panel so it was flush, then tacked down the four corners when I was confident the parts would line up with the holes. Once I verified that the parts were flush against the PCB, I added nuts to those parts to pull the panel straight and soldered in the rest of the panel parts. I did the little toggle switches last, as they are slightly shorter than the other panel parts. I soldered one pin while pushing up on the switch from below, then made sure it was flush to the board before soldering them all the way.

3. This one is for people like myself with less than ideal eyesight. There are 3 18k resistors, and if you are absentmindedly stuffing your board and not looking closely, it's possible to mistake the "18k" as "10k". This probably won't be an issue for most, but I sometimes switch to autopilot when stuffing resistors, and have so far resisted switching to bifocals.

4. There are two 1n capacitors, one of which is polystyrene. Looking at the original schematic, it looks like the polystyrene should be C9 on the pharmasonic boards. That capacitor sits a bit high, and will need to be bent a bit to fit when the PCBs are mounted together.
Image
5. Notice in the above picture that there's a little gap between the headers if you mount them flush to the boards, due to the standoffs being a hair taller. They make full contact as shown. I continuity tested all of the connections before soldering just to make sure.

6. The last parts I soldered in were the trimpots. Some of the pins are fairly close to caps, so steady those hands before soldering so you don't melt anything! It would be far more annoying to solder the trimpots in first and have to avoid them as you soldered everything around them.

Calibration is a bit more involved than some VCOs, but not too bad. The instructions say to set VR1 "halfway" which is not really possible to do visually if you are using multi-turn trimmers. I used a multimeter to make sure it was in the middle. This can be done before or after the trimmer is soldered in.

I'm not sure if the calibration instructions in the build doc are directly from the original service documents or not, but I couldn't match the exact process. With the range at 2' I was not able to get the VCO down to 1760Hz as described. To calibrate the range, I ended up setting the VCO at 16000Hz at 2' and 1000Hz at 32'. For the final adjustment, the tuning step, 8' was not able to be tuned to 440, so I set it a couple of octaves higher.
To follow the exact calibration procedure, you will need a CV keyboard, but I did most of it with a MFOS V/Oct calibrator. Being able to play A3 really only matters if you want the VCO to be at that pitch when the pitch and semitone knobs are at 0.

I would classify this as an intermediate build. I would not recommend it is a first build, but then again I've seen people build entire 4U panels as their first project. I built this over about two days. If you pushed yourself, you could do it in a day, but I prefer calibrating and troubleshooting "fresh". That gives me the patience to find and fix issues should any come up. Tired appliancide is a crappy tech!

I tore apart my workbench and music table after I finished this build yesterday, so its' going to be a couple of days before I can post some audio demos. I will definitely be posting ndkent's request, as well anything else I can come up with that might be useful or interesting.

Feature-wise this seems like it's going to be a great VCO. The 1/10 switches on two of the three modulation inputs are a very cool feature. Not something I would have ever thought of, but can definitely see potential uses. The positive-only sawtooth and square waves are interesting. I assume there's a reason for that? Curious if there's much of a sonic difference.

It's very pretty when finished.
Image

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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by ndkent » Sat Sep 19, 2020 3:29 am

Thanks appliancide for that build report. I just built two, one from the kit, one with parts I sourced myself.

Can confirm, IC10 DOES NOT WORK with the kit supplied LM301AN, the pulse out fails.
I had an extra TI brand LM301AP to swap which worked.

My faceplates are not perfectly flat but nearly so.

Agree the "0" with a slash and "8" look very similar in the PCB font used.

VR1 was intended to be a single turn trimmer - looking at the footprint, so half way would be achievable.

Found the styrene cap confusing too but not too hard to figure out by elimination. The film cap has a drawn footprint.

I swapped less common 11mm standoffs myself, the gap with the supplied 12mm isn't too bad imho so I really didn't have to swap.

I've been encountering issues with my sync. One build's sync seems to work, ironically it works best with the positive only pulse wave from the other 702, but I've not quite figured out if I'm getting what I should be in terms of sync sound.
Last edited by ndkent on Sun Sep 20, 2020 1:43 am, edited 3 times in total.

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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by synthcube » Sat Sep 19, 2020 9:14 am

thanks for the confirmation on the LM301 issue- we will amend the BOM for 'LM301AP' ONLY for this kit...
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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by appliancide » Sun Sep 20, 2020 11:21 am

ndkent wrote:
Sun Sep 13, 2020 3:48 pm

Strong Sync, changing external frequency higher
Weak Sync, changing external frequency higher
Strong Sync, changing external frequency lower
Weak Sync, changing external frequency lower


Is this helpful? Arbitrarily picked the frequencies, and used the Teezer sawtooth to sync.

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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by appliancide » Fri Oct 30, 2020 3:00 pm

Image

704 VCA Build Report:

Here is an interesting thread about exponential VCA calibration. When I got to that step I set unity and then used this online calculator to figure out the dB adjustments, as I do not have dB meter. I only bothered calibrating 0db, -10db, and -20db and figured the rest would be close enough for me.

I wanted unity gain at 5v instead of 10v, so I swapped the 68k resistor R17 for 120k, which worked great. If you only change this, the VCA gain pot will go well beyond unity gain, which for me is fine. I like having extra gain on tap wherever possible. If you wanted it to be unity gain at 100%, you would have to swap out R4 for a higher value. Somewhere between 270k-330k would probably work well there, but I did not try it.

The only troubleshooting I had to do was self-created (either a solder blob, or my mini doepfer case is starting to experience some occasional power issues). This was a beta kit, so I can't comment on whether or not any capacitors will need to be bent to clear the front panel, but that's a pretty standard thing to watch for when building modules with PCB-mounted panel parts.

Here's a not-very-good partial time lapse video with unrelated audio:

Last edited by appliancide on Fri Oct 30, 2020 3:10 pm, edited 1 time in total.

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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by appliancide » Fri Oct 30, 2020 3:09 pm

Image

723 Analog Switch Build Report:

Not really much to say about this one. Easy to build, and a lot of fun to use. The only instructions in the build documentation are which 4 resistors are 47k instead of the silk screen designator of 10k.

Here's my second attempt at a build video:



Better than my first attempt, but my presentation needs some polish yet. I think in future videos I will do the audio editing outside of the video editing program for more control, as that is wonky in OpenShot.

A friend and I are working on a gear demo and DIY build show with a focus on noise and experimental music. We will definitely be looking at this module in more depth at some point, as I think it has a lot of potential for crazy cut-up as well as the more traditional patches shown in the System 700 owner's manual.

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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by ndkent » Sat Oct 31, 2020 5:39 am

704 VCA comments.

The 100u caps need to be 10mm tall or shorter to clear the front panel. This is a general rule for Pharmasonic PCBs. They suggest Mouser 647-USR1C100MDD, which is a Nichicon 16v. No reason to use that exact one but I've found my own 25v caps tend to be too tall.

Pharmasonic uses symbols to identify their often used transistors. I notice the symbols were not reprinted on the VCA doc -
Screen Shot 2020-09-10 at 10.03.51 PM.png
There are no 2SK30As in the VCA, just including for completeness.

Alternately-
T1, T2, T3 T4, T5, 2SC945-Q
all these are “T#”

TR1, TR2, TR3, 2SA733-Q
all these are “TR#”

Finally while I forgot where I found the 700 User Manual online, surprisingly the original Roland calibration info is in the back of the User Manual.

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Re: [AVAILABLE] Pharmasonic Series 700 VCO synthCube kits

Post by appliancide » Sat Oct 31, 2020 8:21 am

I forgot to mention the transistor thing on the VCA. That key would have been very helpful! I ended up looking at how many of each transistor were in the kit, then comparing that to the "T" and "TR" indicators. I'm told that Pharmasonic is working with synthCube to provide updated schematics and build documents for these modules, so that will be a welcome development.

I found the owner's manual and schematics hosted here:
https://www.synthxl.com/roland-system-700/

Florian Anwander also has the individual schematics hosted here:
http://www.florian-anwander.de/roland_system700/

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by appliancide » Sun Nov 08, 2020 9:05 pm

Image

703F 24dB Low Pass VCF Build Report:

I didn't run into any gotchas stuffing the PCBs, other than having to bend a couple of electros over to fit under the front panel. There was a bit of a curve on the front panel (just a hair really), so I soldered the jacks to the front panel PCB after test fitting everything, then used them to line the panel up before soldering the pots and LEDs.

The first step of calibration has me scratching my head a bit. From the build notes:

"The 703F filter has something quite unique, it has an offset trimmer for each pole.
Don’t feed the module with any audio or CV and set all pots fully CCW.
Set your oscilloscope to DC (using high gain) and adjust each pole’s offset to 0V
starting with the 1st pole."

With all of the pots turned counterclockwise, I didn't see a DC offset at any of the test points, even after adjusting the trim pots back and forth. I'm wondering if that's expected, or if maybe I should have had the cutoff turned up? After I messed with that for a while, I moved on to the last two steps of calibration, which were easily dialed in.

edit: found this in another thread:
Modulart_JP wrote:
Sun Sep 22, 2019 8:57 pm
I have my scope set to 50mV and all pots fully CCW.
Set your scope to 5mV.

Frankly speaking, it does not make a difference and I kept those trimmers for each pole to be thorough, stay true to the original schematics.
The truth is that many filters in other Roland synths have a similar filter and they did omit those trimmers.
I think they realized it was not worth it.

If you can do it, fine.
If not, don't bother...
:tu:
It sounds great! I wasn't sure what to expect, since the handful of System 700 demos out there all seem to use the 703ABCD multimode filter. Compared to the 4075 (the only 24dB VCF I have on hand to compare it to), it sounds a bit more vintage and rubbery. I will post the build video after I edit it, probably next weekend. Let me know if there's anything you want to see or hear.

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by appliancide » Sat Nov 14, 2020 7:12 pm

Here's the build video/sound demo:



I never realized how many filters Roland made that were similar in architecture and sound to the SH-101. Obviously this one and many of the others came before the 101, but that and the Jupiters were always my reference point for the Roland sound.

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by appliancide » Thu Dec 10, 2020 6:58 pm

I found a good deal on a Doepfer LC9V in BST. Fits the look of the Pharmasonic modules perfectly IMO. I haven't moved all of my 700 clones into it yet, because I'm really happy with my setup as it sits, so they will be moved there as I finish new modules.

Image

710 Multiple and 716 Mixer Builds:

Image

Not much to say about these. Two easy builds with no calibration needed. Took me less than an hour to build the two of them.

713 Gate Delay/Voltage Processor and 708 Ring Modulator/Noise Generator Builds:

Image

A couple more easy ones. No calibration needed on the 713. The calibration on the 708 was pretty straightforward. I visually set the noise level at first based on a few peak voltages I saw on the scope, and that turned out to be a bit quiet for me, so I had to readjust. No big deal. You could do the calibration on the 708 by ear if you didn't have a scope.

I have a 707 Amplifier/Envelope Follower/Integrator almost complete as well. I'm just waiting on a switch to finish that one. I'm working on a build video for all five of these which, as usual, will feature some audio examples of the all of the Pharmasonic stuff I've built so far.

The size-per-function of the utility modules in this range might not be for everyone, but I really like the look.

edit: let me know if there's anything you want to hear or see

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by ndkent » Fri Dec 11, 2020 3:05 am

716 super easy build, not HP efficient.

708 - curious what exact part number for the noise transistor?

Basically have been getting very low level output or glitches or hum/oscillation. I've spent loads of time swapping parts and eventually put a socket on the reverse and flipped the transistor so I can try a few, went through different versions of the ICs too which do change the results. Some research seems to indicate Roland in the 70s used to go through large quantities of 2SC828-R to find defective noisy ones, but it's no longer cheap and I doubt newly made ones have the loud noise. more observations here viewtopic.php?f=17&t=221906&p=3367775#p3367775

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by appliancide » Fri Dec 11, 2020 5:07 pm

ndkent wrote:
Fri Dec 11, 2020 3:05 am

708 - curious what exact part number for the noise transistor?

Basically have been getting very low level output or glitches or hum/oscillation. I've spent loads of time swapping parts and eventually put a socket on the reverse and flipped the transistor so I can try a few, went through different versions of the ICs too which do change the results. Some research seems to indicate Roland in the 70s used to go through large quantities of 2SC828-R to find defective noisy ones, but it's no longer cheap and I doubt newly made ones have the loud noise. more observations here viewtopic.php?f=17&t=221906&p=3367775#p3367775
I have been building beta versions of the synthCube kits, so sometimes have to use my own parts as kitting is not always complete when I get them. The 708 kit did include a 2SC828-R though, and I have volume to spare. I can get the noise output hotter than a VCO out easily. I think some variance in noise level is typical when using transistors, but I've always been lucky (or modern parts are better suited for noise), and just used the first one I've grabbed on modules I've built with NPN-based noise.

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by ndkent » Fri Dec 11, 2020 10:34 pm

708 good to know.

I built the System 100 Noise but that's quite a different design (discrete, no ICs) though 2SC828 as a noise transistor with good results.

On the 708, I could get the level quite high too, but the pink noise was seriously flawed when I did. Get the pink noise acceptable and the white was real low. Guess I need to troubleshoot more. I know the first thing I'll do is swap out that mutiturn pot.

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by appliancide » Thu Dec 17, 2020 10:35 pm

707 Amplifier/Envelope Follower/Integrator Build:

Image

Another fairly quick and easy one, with a single trim pot to adjust when you are done. I moved all of the System 700 clones into the Doepfer case posted above, but it's too dark to get a good picture at the moment.

A quarter inch input would have been nice for the amplifier section, but I have plenty of little adapter boxes and cables, so that's a non-issue for me.

I am working on a build video for last five modules I posted here. It may be a bit on the ridiculous side, but that's how I roll. If you have any sounds or functionality you would like to see/hear demonstrated in the video, let me know.

edit: I may have to do a psuedo-AMSR video of me peeling the plastic protectors off of the chrome part of the knobs once I figure out a good way to do it without scratching the spun aluminum part. I don't think I've done any of the ones I've built in the last year.

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by appliancide » Thu Dec 31, 2020 3:26 pm

709 S&H Build:

Image

edit: please forgive the terrible lighting

Another pretty simple one. I’m curious if anyone else has built this one yet. With parts specified in Pharmasonic’s BOM, the clock really only works on the last 1/4 of the pot rotation. I’m wondering if a resistor change would help that. I don’t plan on using it as a clock module too often, but it’s nice to have the option.

I had a bad 3140 that kept the module from working correctly at first, but luckily had a good one on hand. I suppose I should have taken a picture or noted the markings on the bad chip. I think it happened to me once before when I built Ian Fritz’s ribbon controller. Not sure if 3140s are more sensitive, or maybe had some bad batches?

This is another module that isn’t super space efficient, but if you are going for a nice little System 700 setup, it fits the bill.
Last edited by appliancide on Thu Dec 31, 2020 11:08 pm, edited 2 times in total.

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by ndkent » Thu Dec 31, 2020 6:29 pm

709 S&H.
Built it a while ago with the Pharmasonic BOM.

Used the Mouser 3140 - CA3140AEZ

No issues. Next time I use it I'll check the clock range. It seemed ok but maybe I'm forgetting and figured I could use an external clock to get some other speed.

Actually the System 100 S&H is what I've had trouble with. It's a different far more compact design but still debugging.

Note that there is a resistor change on the Pharmasonic site to get the external clock to work with 5v trigs.

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Re: [AVAILABLE] Pharmasonic Series 700 synthCube kits

Post by appliancide » Thu Dec 31, 2020 11:25 pm

I'm sure the good part I swapped in was also from Mouser. At over $2 a piece there's a less than zero chance that bad/out of spec/fake parts can make their way into the market.

On the plus side, I swapped the sampling cap with a 1% film cap I had left over from building the JH frequency shifter while I was troubleshooting, so I shouldn't have to deal with much droop!

Here's my System 700 case (with a few overflow strays from my other cases) as it sits now:

Image

I think it's going to look really cool when it's all black and chrome!

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