FM Ogre is now completely CC-BY-NC-SA / GPL Version 2 !

Anything modular synth related that is not format specific.
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FM Ogre is now completely CC-BY-NC-SA / GPL Version 2 !

Post by wsy »

(if you don't know already- the FM Ogre is a Thru-Zero reimplementation from
scratch of the "FM Operator" made famous in the Yamaha DX-series synthesizers.
With extra superpowers, of course. See the FM Ogre topic for details; I'll be posting
help and info here as needed)

I've spent a year now trying to find a path to get the FM Ogre out there into
commercial production, and given $DAYJOB I honestly don't have the attention
budget to handle the extra CPU cycles. I'm gonna short-circuit my tale of woe
and schedule and budget and QA and lining up assemblers, and just get this thing
out there.

Meanwhile, there's a vibrant business of third-party builders out there who I should
tap into, but haven't yet.

So, that in mind, I'm releasing the FM Ogre as CC-BY-SA-NC. (EDIT: NOW DUAL
LICENSED CC-BY-SA-NC and GPL version 2) That is, make it yourself. It's
open source, both in hardware and software. Make all you like. Change it if
you like, and as long as you keep attribution, you can share it out.

I know that all of the parts are easily purchased from DigiKey and any decent
board house can make the PCB board (OSH Park will make you three for fifty
bucks). The software (source included) download requires a PICKit 3 or
equivalent, but you can probably borrow a PICKit if you don't have one yourself.

Yes, it's surface mount. But there's plenty of people doing surface mount these
days with nothing but a superfine tip on their Weller. It's eminently doable that
way- ask my beta testers.

Build them, mod them, enjoy them. Even give them away. Just don't _sell_ the
FM OGRE without getting permission from me first (for a very nominal fee, I assure
you. Or, if you can adhere to the GPL, FOR FREE (though again, beer money is
always appreciated).

And- if you build one (or a few)- let me know. I'm interested to see what kind of legs
this thing has.

Note that there is a Live BOM is actually encapsulated in the Fritzing .FZZ file, so no separate BOM file except in the Gerber .zip file.

You should also read the (rather long) FM Ogre design topic:

viewtopic.php?p=1839452#1839452

for insight into how this came to be, and why some parts were chosen in particular.

Here's the direct link to the OSH Park PCB order/annotate project:

https://oshpark.com/shared_projects/n2OCm4Pw

(note that this board has the MobLith fix and nothing else changed, so it should be perfect, but then again, V097 was that way too. May I suggest that the first person
to order it put in a note here so others more timid (or wiser) might wait to verify that
the PCB doesn't need any ECOs whatsoever?

- Bill
Attachments
FMOgre_DMA_Main_Golden_20160907.c
No known misbehaviors, well tested, 1.5 Hz to 18..9 KHz range, smooth PM, superior decimation. Use this one, please.
(36.83 KiB) Downloaded 61 times
FMOgre_DMA_Main.c
Full input DMA in this version. Bangs the ADCs pretty much as fast as they can go. Same UI as below.
(32.38 KiB) Downloaded 58 times
FMOgre_switches_scrub.c
This is the "scrubbed" version which has the same UI but the phase jitter is now way, way down, and SAMPLE uses the FEEDBACK CV input. Use this one for best results.
(28.74 KiB) Downloaded 58 times
FMOgre_switches_main.c
Full "You're In Bat Country" mode. S1: VCO/LFO. S2: Phase Mod / Resolution grinding. S3: SINE / SAMPLE to final wavetable. Sync In jack: Hard Sync in sine mode / Freeze Sample in SAMPLE mode. Gapless realtime splicing if you sync your sour
(28.36 KiB) Downloaded 67 times
DSPICable-44-V099.zip
This is the ZIPped up Gerbers for PCB production (also a copy of the HTML version of the Live BOM and a PNG of what the board looks like for reference). Use this to order boards if you don't want to edit the board at all with the FRITZING software packa
(910.97 KiB) Downloaded 126 times
wavetable.h
The precision sine and 1V/Octave tables. just data, but needed by the main program
(139.9 KiB) Downloaded 106 times
dspicable-44_099.fzz.txt
The schematic and layout, in Fritzing format (Fritzing is an open-source E-CAD package).
Due to the MW posting system, it's been renamed ...fzz.txt. Just drop the ".txt" and open with Fritzing
(292.61 KiB) Downloaded 152 times
Last edited by wsy on Wed Sep 07, 2016 6:47 pm, edited 19 times in total.
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Post by Maco »

:yay: :nana: :bananaguitar:
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Post by yan6 »

Bill, thank you for your hard work on this, I'm sure the community will be really excited to get these built, I know I am! Could you tell me which software you were using for your layout.

Have you already loaded the boards to OSH Park, if so could you post the link.
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Post by wsy »

yan6 wrote:Bill, thank you for your hard work on this, I'm sure the community will be really excited to get these built, I know I am! Could you tell me which software you were using for your layout.

Have you already loaded the boards to OSH Park, if so could you post the link.
The software is Fritzing. I did put the boards on OSH Park, but the last run wasn't set
as world readable so yes, that's an update I should do.... after dinner!

I guess I should also post a zipfile of the Gerbers so anyone who wants to just
run boards can do that.

- Bill
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Post by jsleeio »

Wonderful, thank you so much for doing this! <3

Folks in/around Sydney, Australia - I plan to do a PCB order and when I have them, I'll bring to a New Sound Waves meet. Please email me at <bessie@tastyco.ws> if interested ***and you can get to a meet*** (I'm not interested in posting them; my work makes it a PITA to get to a post office), rather than cluttering up this thread.
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Post by wsy »

indigoid wrote:Wonderful, thank you so much for doing this! <3

Folks in/around Sydney, Australia - I plan to do a PCB order and when I have them, I'll bring to a New Sound Waves meet. Please email me at <bessie@tastyco.ws> if interested ***and you can get to a meet*** (I'm not interested in posting them; my work makes it a PITA to get to a post office), rather than cluttering up this thread.
We might want to coordinate so that we place one order to someone who wants to build RIGHT AWAY and has the time to do so RIGHT AWAY, so we can get a final field test
before too many people place orders for boards that might need an ECO.

But then again, the board is just two layers, and so even the worst ECO is easy with an
X-Acto knife.

- Bill
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Post by jsleeio »

Seems sensible. I'm not in a big hurry. Just putting it out there

That said, unless there's a whole lot of boards, it may make more sense to just leave it to individual OSHPark orders. I ordered a whole bunch of stuff through them recently and it seemed quite reasonably priced considering the usual cost of shipping stuff Down Under
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Post by EMwhite »

Bill, I can't follow any of this because it's too complex for me; Very similar to when I was a kid, a whiz at 'C' programming but just couldn't grasp object orientated design, so I gave up :hihi:

On synths, I'm stuck with analog waveforms on my 921 clones, etc. but...

Hats off for all of the work you put into this project.

And there is nothing more admirable than when projects are put into open source. You, Tom Whitwell, Olivier from Mutable, etc.

Have you watched the Yamama NAMM walkthrough, which pends some time on the DX technology; inspiring for those that may not have seen it: http://www.sonicstate.com/news/2015/01/ ... seum-tour/ <-somewhere in the middle
Beware of programmers with screwdrivers...
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Post by diablojoy »

I will look at a board order soonish , bit busy with work at the moment -silly season and I am presently over extended on other projects to boot
however I will get there.
It probably wont happen today but if it does it definitely wont go smoothly.
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Post by batchas »

wsy wrote:FM Ogre - going CC-BY-NC-SA
:hail:
EMwhite wrote:Hats off for all of the work you put into this project.

And there is nothing more admirable than when projects are put into open source. You, Tom Whitwell, Olivier from Mutable, etc.
+1
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Post by Dogma »

This is just so generous of you. There could be a designer on the cusp who takes this project to where you intened. And I think I know the person.


Please just a few questions though - Ive been reading up on MOdcan and how they implement it in the FMVDO - does this use an NCO? Do we know what the max resolution - 50k? 100k?

Im very exited by this!
look up!
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Post by wsy »

Dogma wrote:This is just so generous of you. There could be a designer on the cusp who takes this project to where you intened. And I think I know the person.


Please just a few questions though - Ive been reading up on MOdcan and how they implement it in the FMVDO - does this use an NCO? Do we know what the max resolution - 50k? 100k?

Im very exited by this!
Why, thank you! Don't think of this as generosity though. Think of it as cussedness. :-)
And, possibly, self-greed/self-budgeting. To quote the Book of Clint: "A man's gotta know
his own limitations." - and I don't have the cycles to do this any other way.

As to NCO? Well, there's a phase accumulator, but no oscillator "per se" - the phase
accumulator (32 bits, resolution is one part in 4 billion) simply wraps around and
the high-order bits go into the sine table for output. The increment happens "inside"
the timer interrupt that fires off the next word into the output DACs, so there's
no gritty race condition.

Resolution? I'm not quite sure what that means; the input ADCs run at 14 bits and
500KHz round-robinned around the 8 inputs but there's jitter smoothing so it's finer
than what 14 bits ought to sound like (and at 500 KHz, there's no zipper at all).
The output DACs run at something like 90KHz and 16 bits input, but inside them they
have dedicated hardware to do 256x oversampling, so the output is really, REALLY
smooth, in fact it's a better sine wave than my JYE signal generator can make. Possibly
it's the best sine wave in the house.

Now, the FMVDO claims to have two operators; I'm not quite seeing that looking at the
block diagram and text here:

http://ebrombaugh.studionebula.com/synt ... index.html

but maybe Eric is just glossing over that detail or I'm not understanding it.

How it Works, In More Detail:

Anyway, what's happening inside the FM Ogre is that the tail wags the dog. More
precisely, the output DAC wags the dog from one end, and the input ADCs wag the
dog from the other end. In the middle, there's growling and barking but only things
that don't have to happen in precise realtime happen in the middle.

The 256x 90+KHz oversampling DAC has an input queue on it four samples deep, and
is clocked directly from the 80 MHz system clock. Whenever the DACs have space in their queue for another sample, they fire off an interrupt that runs the realtime part of the
FM calculation:

* the current pitch DAC knob and jack go through exponential conversion lookup in a full resolution table in EEPROM to get the actual increment of phase for this DAC cycle

* the phase accumulator gets incremented and saved, the feedback is calculated, the results of that are added together and goes out on the Frequency and Feedback DAC port.

* the current phase accumulator plus distortion amount plus the phase and goes out on the Frequency, Feedback, and Phase Mod port

Why I did one output as frequency and feedback, and the other as frequency, feedback, and phase rather than quadrature: Because it makes funner noises that way. :-)

... and that's one tail wagging the dog.

The second "tail" is the interrupt on the ADCs. Those interrupts happen at about 500KHz
whenever the ADC finishes a cycle. The ADC mux gets switched to the next of the
eight inputs, and starts charging the on-chip sample and hold input capacitor again.
While it's charging, the ADC output from the previous input is still in the ADC latch, and
gets copied to a static location in DSP memory where the DAC interrupt can find it.
As soon as the sample and hold has charged, the ADC gets fired again, to convert
the next input as quickly as possible (inputs are 14 bit, by the way, but jitter and
smoothing give you 16-bit silkyness)

All eight inputs get muxed the same way (although there is provision in the code to
give some inputs service more often than others, it turns out to be totally unnecessary
as NOBODY can hear an 80 KHz "zipper"..... :-) )

Finally, there's the dog in the middle. This is the code that's running whenever the DSP
isn't busy either pushing stuff out the DAC or in the ADC. This code turns on and off
the LEDs for activity, negative frequency, and negative phase, and also services the
SYNC IN and SYNC OUT (neither is precise to the same accuracy as the DAC or ADC,
nor can they be, because of the non-disableable hardware queue in the oversampling
DACs which insert a constant time (rather than constant phase) delay in the passing
data stream. I spent a lot of time trying to build a frequency-based workaround
and it's just really unnecessary)

So, does that help?

- Bill
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Post by aladan »

diablojoy wrote:I will look at a board order soonish , bit busy with work at the moment -silly season and I am presently over extended on other projects to boot
however I will get there.
Hi diablojoy,

I'm in Adelaide and would love to grab a board or two from you when you get them done, if the offer is open.

Thanks,
A.
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Post by LudfisterSound »

Can't wait to see a build thread get started on this. Thanks, Bill!
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Post by diablojoy »

No problem Aladan
at cost of course
if you can hold off a bit I have a plan to get 10 or so from itead
will try to draw up a plug in panel board for euro - no wiring solution when time allows I am working 70 -80 hours a week at the moment unfortuanately
thinking 12 hp based on that panel I put up in the other thread. 9mm alpha's and erthenvar jacks - would that suit ?
I am no group buy runner- no time for it so sorry no "me too please"
please. :lol:
if I can get a plug in euro panel control board done and tested I will release the gerbers to bill , he can do as he see's fit with them.
It probably wont happen today but if it does it definitely wont go smoothly.
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Post by aladan »

diablojoy wrote:No problem Aladan
at cost of course
if you can hold off a bit I have a plan to get 10 or so from itead
will try to draw up a plug in panel board for euro - no wiring solution when time allows I am working 70 -80 hours a week at the moment unfortuanately
thinking 12 hp based on that panel I put up in the other thread. 9mm alpha's and erthenvar jacks - would that suit ?
I am no group buy runner- no time for it so sorry no "me too please"
please. :lol:
if I can get a plug in euro panel control board done and tested I will release the gerbers to bill , he can do as he see's fit with them.
No hurry whatsoever, and happy to swing you some extra cash for your trouble. I'm 5U in DIY so I won't need the euro boards but I understand if you're copying and pasting and they come as part of the deal.

And I'm only jumping on board because you're in Oz and we've done deals before :)

And I'm only having this discussion in the thread because my damn Muffs PM box is still 500% full and I've been too busy to do anything about it and there are important messages with links to build docs buried in there so I don't want to bulk delete!

:whistle:

Cheers,
A.
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Post by synchromesh »

Hi Bill,

Just wanted to add my thanks for (a) putting in the effort to develop all this and (b) deciding to open-source it all (whatever your motivation might've been). I'll definitely be getting a board or three made at some point! :tu:
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Post by wsy »

OK, two people/groups have signed on to wanting the "commercial" license; the terms
are pretty simple:

If you build for yourself, or build as part of a group, you don't need a license; you're
covered under the GPL and Creative Commons licenses.

If you build for sale, then you need a license.

I figured if Tom Wiltshire (Electric Druid) can get $10 a piece for his PIC-chip TTLFO
that has a 50-cent PIC chip pre-programmed with his software, then that's probably
a good price - practically a "no brainer" for a module, so the license fee for
commercial sale is $10 a unit for new units.

What the $10 gets you:

1) Basically, good karma, proper ethics, stuff like that.

2) Free updates of the single-operator FM DSP software. (note that the board is
itself a general purpose DSP for audio with proper inputs and outputs for modular
synth levels; expect more ideas to come of it. You don't get those for free, except
that they're likely also GPLed, so if you install them yourself, you're still OK :) )

3) Some gratis one-on-one consulting. How much? Well, I want this to succeed,
but I also have $DAYJOB and $FAMILY.

4) NO WARRANTY. The hardware and software work for me (three buildouts!) and
for all the beta testers who've reported back. But still, no warranty.

5) License is nonexclusive (other people can get them too). Build for any format
you want (MU, 5U, Eurorack, Buchla, or no format at all - just the DSP board). It doesn't
matter, go have fun.

6) Regulatory compliance: This thing is untested, no FCC cert, CE approval, UL stamp, or stuff like
that is available. Read the FCC Part 15 rules yourself; given the "no case, no
power supply, then no cert needed" rule *I* choose to view this as certificate exempt, but I
am not a lawyer.

7) Export control: again, my reading of the export control rules says it's EAR99
(no export control) but I am not an export control guy either.

8) Payment: send me money monthly. If possible, include a list of serial numbers of units you ship. I advise
you come up with a nice personal prefix to the serial numbers, since you don't want to
have to warranty other people's work.

9) No refunds on license fees. Ever. Too much hassle and I'll have already spent it
on beer. Pay only when you ship the board.

10) [EDIT 20150317] Logo - You can put the WSYnth logo on the front panel; I'd
appreciate it if you do, but if you don't, I'll just ... try.... to ... understand.

- Bill
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Grove Audio has signed on as a nonnexclusive commercial vend

Post by wsy »

Good News. Grove Audio has signed on as a nonexclusive commercial vendor.

This means that (hopefully soon) you will be able to write a check and get a module.

I'll leave it to Grove Audio to discuss their business plans.

Note that this is a NONexclusive license; other companies can also produce the module
(bare board, Eurorack, MU, 5U... ) and there's no conflict. In fact, I hope other folks
do so, because that way there's more choice and options.

Of course, individuals and groups can still make them for themselves, no
charge, no license required, either as-is or with changes to the hardware, the software,
or both.

So get goin'!

- Bill
"Life is short. But we can always buy longer patch cords" - Savage
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Post by Dogma »

Well I too am going to be offering modules.......Stay tuned for more details.
look up!
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Post by Joe. »

Sorry if I'm overlooking it, but what are the values of the 4 potentiometers, AN4-AN7?
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Post by wsy »

LoFi Junglist wrote:Sorry if I'm overlooking it, but what are the values of the 4 potentiometers, AN4-AN7?
You aren't overlooking it. Those four pots are on the front panel, not on the PCB,
so they're not on the PCB schematic (Fritzing gets pissy if you don't lay out all of
your parts.)

Anyway, the current is minimal and they're just DC voltages between 0 and 3.3 volts.
I suggest 100K pots (because that's a standard Dotcom pot, which Roger will sell
you with leads and connector attached!).

But any linear-taper pot in the range 10K to 1M will probably work just fine. Use what
you have, what has a nice fingerfeel, and what fits those pretty knobs you got off
DigiKey / SmallBear / an old piece of test equipment you trashpicked. :badger:

- Bill
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Post by wsy »

LoFi Junglist wrote:Sorry if I'm overlooking it, but what are the values of the 4 potentiometers, AN4-AN7?
You aren't overlooking it. Those four pots are on the front panel, not on the PCB,
so they're not on the PCB schematic (Fritzing gets pissy if you don't lay out all of
your parts.)

Anyway, the current is minimal and they're just DC voltages between 0 and 3.3 volts.
I suggest 100K pots (because that's a standard Dotcom pot, which Roger will sell
you with leads and connector attached!).

But any linear-taper pot in the range 10K to 1M will probably work just fine. Use what
you have, what has a nice fingerfeel, and what fits those pretty knobs you got off
DigiKey / SmallBear / an old piece of test equipment you trashpicked.

So, you building just for yourself, or are there now THREE suppliers for this puppy?

:sb: :sb: - Bill
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Old boards have a pot-wiring error.

Post by wsy »

Oh- and for those playing at home, V097 and earlier boards had a consistent
error; the pinout for the pot connectors had two pins switched versus the standard
DOTCOM layout.

The new boards (V099) have that corrected. So, unless you were one of the early
beta testers and have a green board V097 or lower, this shouldn't matter. Only a few
of those boards are out there anyway and any new builds won't be them.

- Bill
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Normalization voltage setting - R39 goes downward, not upwar

Post by wsy »

If you look at the V099 boards, you'll notice down the west side right next to the
AN0 - AN7 inputs there's eight resistors, R39 through R46.

And suspiciously right below them, are pads P1 through P8. At JUST the right
distance away that you can put the 0805 surface mount part 'up' between the
nominal R-pads, or 'down' from the lower R-pad to the P1 through P8 pad.

Those are actually sorta set-once switches. They set the "normalled"
(no-jack-inserted input) voltages for those signal chains for AN0 through AN3, and
the maximum pot voltage for AN4 through AN7.

When resistors R39 through R46 are placed as drawn on the silkscreen, they all
"normal" to maximum voltage. That's probably what you want for all but the
pitch (1V/octave) input (AN0), which would then make the operator output run up to 32KHz.

So instead, place R39 (and R39 only) in the lower position, between the lower
pad of R39 and the pad P1.


Note also that you can customize around this as well; all eight ANx inputs are fully
protected and have a 100Kohm input impedance even if you don't use the normalling.
So, if you wanted to build a 4-operator voice you could leave off some of those
resistors and solder right to the R39 through R46 pads and everything would work.
(well, modulo that AN0 through AN3 are set for -5 to +5 inputs, and AN4 through AN7
are set up for 0 to 3.3 volt inputs). They all have protection circuits though, so
you are unlikely to actually hurt anything.

- Bill
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