Which system/module to start building? (aiming at the bananas)

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Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Thu Mar 19, 2020 12:04 pm

Hello! It's been four years that I stopped using Eurorack. ;) Recently I started sDIY-ing (my electronics knowledge is very shallow yet). Building the Lunetta-style machines and fuzz pedals currently. So far what I enjoy the most is building from a schematic, using the breadboard-style through-hole boards etc. and adjusting things on the way.

I got a bit tired of the square-wave drones so now I'm looking for a well documented system or a module/collection of modules to slowly make a more or less coherent modular system for myself starting with a schematic. My preferred connector is the banana. Aside from the obvious Serge I looked into a few popular systems like MFOS, yusynth and CGS.
The most logical choice seem to be the CGS. I also really like how Loudest Warning's panels look but having to make my own panels is ok. I also haven't decided to make it a 3U or 4U yet. I'd go full Serge if the schematics and components were available (73-75 Serge looks interesting and it seem to have schematics in the manual). I don't need PCB's to be available, it could be useful but I want to make my own layouts.

Please tell me if there is a system or a module out there that meets the following criteria:

Schematics and Design:
[ ] schematics are available online
[ ] schematics are detailed and verified
[ ] predominantly analogue design
[ ] banana connectors are assumed (or the S of the TS connector is ignorable design-wise)

Components:
[ ] components are widely available (preferably through-hole)
[ ] no need for the pre-programmed ICs

Power:
[ ] +/-12v, 5v (will start with a Euro supply)

Any suggestion is welcome! Thank you.

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Re: Which system/module to start building? (aiming at the bananas)

Post by luchog » Thu Mar 19, 2020 12:11 pm

There are quite a few resources for Serge and similar stuff -- Elby Designs, Loudest Warning, Random*Source, Zthee (aka 73-75, aka The Human Comparator), and of course CGS. And the Serge world has generally been more friendly for DIY efforts. And the Serge 4U format also has a few others providing compatible DIY options, such as Ian Fritz, Craig Lee, and Jürgen Haible.

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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Thu Mar 19, 2020 12:31 pm

Thanks for the reply, luchog! I'm aware of the designers and the manufacturers you've mentioned - I just got the impression that a lot of the Serge schematics are not as widely available online as for example CGS. And with the Ken Stone and Ian Fritz designs I see a lot of the outdated components that kind of scare me off. I surely need to take a deeper look into it, though.

(note to self: Befaco stuff looks promising)

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Re: Which system/module to start building? (aiming at the bananas)

Post by luchog » Thu Mar 19, 2020 1:00 pm

Parmesan wrote:
Thu Mar 19, 2020 12:31 pm
Thanks for the reply, luchog! I'm aware of the designers and the manufacturers you've mentioned - I just got the impression that a lot of the Serge schematics are not as widely available online as for example CGS. And with the Ken Stone and Ian Fritz designs I see a lot of the outdated components that kind of scare me off. I surely need to take a deeper look into it, though.

(note to self: Befaco stuff looks promising)
The Random*Source stuff has a good deal of the old Serge, Ian Fritz, and J.Haible circuits updated to use more modern components. IIRC the only outdated components they still use are some of the less commonly available BBD chips for the SOST flanger, and they appear to have those available as part of the PCB+rare parts kit.

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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Thu Mar 19, 2020 1:11 pm

I couldn't find R*S schematics online. I'll definitely take a deeper look into Ian Fritz and J.Haible schematics.

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Re: Which system/module to start building? (aiming at the bananas)

Post by KSS » Thu Mar 19, 2020 1:32 pm

Look up Scott Bernardi's Lockbox, Ogee2 and Ogee 3. Older but still very buildable.
http://www.bernacomp.com/elec/og2/about_me.html

Can't remember the guys name but he does work under the Tellun name.
http://tellun.com/motm/diy/diy.html

Then there's Rene Schmitz, whose schmitzbits site is a wealth of nice schematics.

And also Swedish SDIY guru Jorgen Bergfors.

The Electro-Music forum has a thread about synth schematics in their DIY mdular section.

Befaco is a good choice too.

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Re: Which system/module to start building? (aiming at the bananas)

Post by cygmu » Thu Mar 19, 2020 2:14 pm

There are obviously lots of choices available but if you are attracted to Serge then you could start by making a small system akin to the STS Serge Creature:

- DUSG: available as CGS114, https://sdiy.info/wiki/CGS_Serge_dual_u ... _generator
- SSG: available as CGS92, https://sdiy.info/wiki/CGS_Serge_smooth ... _generator
- VCFQ: available as CGS112, https://sdiy.info/wiki/CGS_Serge_voltag ... nce_filter
- some VCAs of your choosing or a crossfader or whatever you like. There's the Stroh FadeX for example.

The only ting in this list without an obvious public schematic is the gain cell submodule for the VCFQ, but you will find that if you search for a while. And Serge apparently doesn't like people DIYing that submodule any more, or at least doesn't think DIYers can make one worthy of the name "Serge", but YMMV.

I am sure Loudest Warning panels would be available for all of that and you'd have a great starter system.

Edit: thinking about the Stroh FadeX gave me the thought that perhaps a few of the Stroh/J3RK designs would be nice to work with too. They are mainly for +/-15V but readily adaptable. Docs and schematics etc available here: viewtopic.php?t=150552&highlight=

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Re: Which system/module to start building? (aiming at the bananas)

Post by EATyourGUITAR » Thu Mar 19, 2020 3:34 pm

in my opinion, and this is just my opinion, banana style synthesis is for people who love to build from scratch and don't care too much about shielded cables or noise floor. if you buy the absolute cheapest nana jacks and you use scrap metal for panels then you can just build a massive synth for almost nothing. the time investment is huge though. maybe you want to have an endless project. sure there are many kits and counter examples to my opinion. but I never found anything about the format to be better. maybe the self cleaning jacks. if you go expensive or cheap on the jacks, you should still spend the $$$ on the pamona cables. you can always sell them off later. you get what you pay for. that could be $400 in nana patch cables but $150 in eurorack 3.5mm mono cables. think about that before you start.
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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Fri Mar 20, 2020 5:15 am

KSS wrote:
Thu Mar 19, 2020 1:32 pm
http://www.bernacomp.com/elec/og2/about_me.html

http://tellun.com/motm/diy/diy.html

And also Swedish SDIY guru Jorgen Bergfors.
I didn't know the quoted sources. Seems very interesting.

Also thanks for reminding me about the Rene Shmitz site too, I ran across it when I just started but somehow forgot about it.
I actually almost never read anything outside the Lunetta section of the Electro-Music forum so that's also a nice idea.

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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Fri Mar 20, 2020 5:31 am

cygmu wrote:
Thu Mar 19, 2020 2:14 pm
There are obviously lots of choices available but if you are attracted to Serge then you could start by making a small system akin to the STS Serge Creature:
- DUSG: available as CGS114, https://sdiy.info/wiki/CGS_Serge_dual_u ... _generator
- SSG: available as CGS92, https://sdiy.info/wiki/CGS_Serge_smooth ... _generator
- VCFQ: available as CGS112, https://sdiy.info/wiki/CGS_Serge_voltag ... nce_filter
- some VCAs of your choosing or a crossfader or whatever you like. There's the Stroh FadeX for example.
...
Edit: thinking about the Stroh FadeX gave me the thought that perhaps a few of the Stroh/J3RK designs would be nice to work with too. They are mainly for +/-15V but readily adaptable. Docs and schematics etc available here: viewtopic.php?t=150552&highlight=
That starter Creature-style pack is indeed interesting. Maybe I'll start with some simpler CGS stuff first though. But all of those modules are on my list.

I once considered ordering some J3RK stuff when I first got the banana fever. I just checked it out and I think I'm building some of it too. Are those schematics made in some kind of a simulation software?

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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Fri Mar 20, 2020 5:49 am

EATyourGUITAR wrote:
Thu Mar 19, 2020 3:34 pm
in my opinion, and this is just my opinion, banana style synthesis is for people who love to build from scratch and don't care too much about shielded cables or noise floor. if you buy the absolute cheapest nana jacks and you use scrap metal for panels then you can just build a massive synth for almost nothing. the time investment is huge though. maybe you want to have an endless project. sure there are many kits and counter examples to my opinion. but I never found anything about the format to be better. maybe the self cleaning jacks. if you go expensive or cheap on the jacks, you should still spend the $$$ on the pamona cables. you can always sell them off later. you get what you pay for. that could be $400 in nana patch cables but $150 in eurorack 3.5mm mono cables. think about that before you start.
I do care about the noise floor to some extent but I have to say that I just like how bananas feel and look too much, so the noise feels like something inevitable. I also think that with a lot of tinkering it could be brought to a usable level. I don't really wanna go faaast, I care more about the educational value of the project and the way I can enjoy creating something. I already feel that sDIY actually is taking the time I actually could use for making some noise - but don't know what is more fun now.
Always hated how pathing the 3.5mm jacks felt, though, exceptionally, I liked the plain round washers that the O|D modules (and maybe Cwejman) had - they kind of support the jack nicely. If those washers were available I might actually go in the direction of the EuroSynth format - don't know the part number though, and if it's not something custom etc.

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Re: Which system/module to start building? (aiming at the bananas)

Post by EATyourGUITAR » Fri Mar 20, 2020 11:53 am

eurorack DIY is more fun if you are also a PCB designer and you can solder small SMD parts. or you can buy kits and solder SMD. or you can buy kits in only through hole. eurorack is where I am at and I don't regret it. what I liked about 5U was that I had room in the case to fit large DIY projects on strip board. the same is true for nana systems. I like 15v systems more but I don't want to spark that debate. if I was building a shitty cheap diy nana synth from scratch I would not gain anything from 15v really. not much. in eurorack 15v would be great but that is impossible. nana 12v with eurorack kits is also a valid option. maybe that is the way? if you need 8 octaves go with 15v. it makes it easier.
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Re: Which system/module to start building? (aiming at the bananas)

Post by KSS » Fri Mar 20, 2020 9:37 pm

A few years ago I would have strongly suggested BananaFrac as format to pursue. and still would if you are a BugBrand fan.

Outside of that, The 4U CGS-LW-CLee DIY is where its at. Right now, it wouldn't make much sense not to go that direction.

Unless you find Andrew Kilpatricks modular format enticing. But as EYG said about Euro, unless you're into PCB design and constrained construction, the ones above may be a better fit.

There is one other banana capable format coming, but the current world crisis has delayed that a bit. And the developer is still weighing DIY vs factory assd.

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Re: Which system/module to start building? (aiming at the bananas)

Post by BugBrand » Sat Mar 21, 2020 4:09 am

As someone who started DIYing modular stuff about 12-14 years ago and has now got to quite a nice place of small scale production.. some thoughts:

- this week I've been trying to help my assistant get started learning schematic/board design software - this made me realise just how multi-faceted the learning ways are! You're learning new (often cranky/esoteric) software AND also likely learning a lot about electronics at the same time. I remember it being a very slow, back & forth process where there weren't many short cuts - learning by doing, trying out a lot. I clearly learned a lot by doing such things and had fun making sounds, but these early experiments don't now feel like a cohesive instrument - in part what I'm saying is that it is quite easy to get a bit overwhelmed by the vast scope of potential & ideas. So, try to move slowly and know that you'll learn through mistakes and simply building projects that might not really 'work' in the long run.

- fully agree with bananas! No issues with noise - they feel great, give great flow. But, yeah, don't cheap out on the parts! Find a type you like & can get regularly.

- do determine and then stick with one format - hard choice of course.. I dipped my toes into Euro but really liked Frac for the wider / standard panel sizes. Set up the infrastructure first - make a reasonable size case with stable power. Should it be +/-12 or 15V? Well, I actually started with 12V, can't quite remember why now.. but a few years later did change up to 15V which is the more standard for Frac. Luckily many designs don't alter much with such a change and it also brings in some useful learning [going back to my assistant - she was looking at the MusicThing Spring and wondering what would need to be changed to take it from +/-12V to 15V - almost nothing as it turns out - just the scaling of the vactrol driver - all the audio circuitry will be fine on either supply with no changes]

- from there, well, many sources for project ideas have already been suggested! Try loads but also try not to get too lost in the vast scope! I personally learned a lot from Thomas Henry and CGS in particular. Try to break down circuits into their building blocks so you begin to understand the underlying structures rather than just copying what has been published - obviously takes some time to get your head round it all.

Good luck with it all!

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Re: Which system/module to start building? (aiming at the bananas)

Post by Isaiah » Sat Mar 21, 2020 5:19 am

KSS wrote:
Fri Mar 20, 2020 9:37 pm
There is one other banana capable format coming, but the current world crisis has delayed that a bit. And the developer is still weighing DIY vs factory assd.
Keen to hear more about this if you’re able to share any information.

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Re: Which system/module to start building? (aiming at the bananas)

Post by KSS » Sat Mar 21, 2020 6:58 pm

Isaiah wrote:
Sat Mar 21, 2020 5:19 am
Keen to hear more about this if you’re able to share any information.
Was gonna be Synthplex, then Superbooth. With both those closed, the next 'synth release reveals' will likely be Behringer's plan to do a 'Billich SB' from their Willich headquarters at the original SB dates.

Still no decision yet whether to go before, during, or after that with it. CV crisis also a factor. But will be sure to let you know once decisions are made.

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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Sun Mar 22, 2020 2:42 am

EATyourGUITAR wrote:
Fri Mar 20, 2020 11:53 am
eurorack DIY is more fun if you are also a PCB designer and you can solder small SMD parts. or you can buy kits and solder SMD. or you can buy kits in only through hole. eurorack is where I am at and I don't regret it. what I liked about 5U was that I had room in the case to fit large DIY projects on strip board. the same is true for nana systems. I like 15v systems more but I don't want to spark that debate. if I was building a shitty cheap diy nana synth from scratch I would not gain anything from 15v really. not much. in eurorack 15v would be great but that is impossible. nana 12v with eurorack kits is also a valid option. maybe that is the way? if you need 8 octaves go with 15v. it makes it easier.
I think I am going to mix surface-mount and through-hole eventually. Sort of Manhattan style, or soldering to the SMT proto-board with holes, I guess. I'm planning to try SMT soon - just need to get an electronic microscope and a better soldering iron. Designing a PCB seems like a good way to make something easily reproducible, but currently I'm just learning so the PCB design priority is low.
I like the portability of the Euro but physically patching Euro - that on the verge-of-instability feeling was always annoying.

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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Sun Mar 22, 2020 3:28 am

KSS wrote:
Fri Mar 20, 2020 9:37 pm
A few years ago I would have strongly suggested BananaFrac as format to pursue. and still would if you are a BugBrand fan.

Outside of that, The 4U CGS-LW-CLee DIY is where its at. Right now, it wouldn't make much sense not to go that direction.

Unless you find Andrew Kilpatricks modular format enticing. But as EYG said about Euro, unless you're into PCB design and constrained construction, the ones above may be a better fit.

There is one other banana capable format coming, but the current world crisis has delayed that a bit. And the developer is still weighing DIY vs factory assd.
I'll read about Frac, always enjoyed to look at how BugBrand modules are laid out. Never seen it 'in person' but the youtube demos sound impressive.
No PCB design for now. Kilpatrick Format also somehow doesn't click with me visually. The format description was a good read though.
Interested to learn about the new format too.

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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Sun Mar 22, 2020 3:53 am

BugBrand wrote:
Sat Mar 21, 2020 4:09 am
As someone who started DIYing modular stuff about 12-14 years ago and has now got to quite a nice place of small scale production.. some thoughts:

- this week I've been trying to help my assistant get started learning schematic/board design software - this made me realise just how multi-faceted the learning ways are! You're learning new (often cranky/esoteric) software AND also likely learning a lot about electronics at the same time. I remember it being a very slow, back & forth process where there weren't many short cuts - learning by doing, trying out a lot. I clearly learned a lot by doing such things and had fun making sounds, but these early experiments don't now feel like a cohesive instrument - in part what I'm saying is that it is quite easy to get a bit overwhelmed by the vast scope of potential & ideas. So, try to move slowly and know that you'll learn through mistakes and simply building projects that might not really 'work' in the long run.

- fully agree with bananas! No issues with noise - they feel great, give great flow. But, yeah, don't cheap out on the parts! Find a type you like & can get regularly.

- do determine and then stick with one format - hard choice of course.. I dipped my toes into Euro but really liked Frac for the wider / standard panel sizes. Set up the infrastructure first - make a reasonable size case with stable power. Should it be +/-12 or 15V? Well, I actually started with 12V, can't quite remember why now.. but a few years later did change up to 15V which is the more standard for Frac. Luckily many designs don't alter much with such a change and it also brings in some useful learning [going back to my assistant - she was looking at the MusicThing Spring and wondering what would need to be changed to take it from +/-12V to 15V - almost nothing as it turns out - just the scaling of the vactrol driver - all the audio circuitry will be fine on either supply with no changes]

- from there, well, many sources for project ideas have already been suggested! Try loads but also try not to get too lost in the vast scope! I personally learned a lot from Thomas Henry and CGS in particular. Try to break down circuits into their building blocks so you begin to understand the underlying structures rather than just copying what has been published - obviously takes some time to get your head round it all.
Thanks for sharing the inspiring thoughts!

I'm currently building the spring reverb from the General Guitar Gadgets schematic adding some elements of the MusicThing reverb. When it's finished I'm planning to start a CGS module. Will probably decide on the mechanical parameters of the format while I'm making the prototype board(s).

My +/-12v choice comes from the availability of it, but I guess the decision should be more consciously rooted in the design. For now I'll try modules that work both on 12 and 15 v.

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Re: Which system/module to start building? (aiming at the bananas)

Post by duff » Sun Mar 22, 2020 4:32 am

If you want banana’s and sDIY theN LW format stuff is great. An easy in is the Slightly Nasty line up with well thought out pcb and panel combinations. After that the CGS boards and LW panels offer up loads of different options in both functionality and build complexity. As mentioned above there are various other makers also offering some great stuff. All this works with euro PSUs and tend to have detailed info about the circuits which is great to learn from.

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Re: Which system/module to start building? (aiming at the bananas)

Post by KSS » Sun Mar 22, 2020 1:58 pm

When choosing rail voltage for a DIY format, consider this.
15V rails can be inexpensively reduced to 12V with 78L12 and 79L12 so that EVERY module designed for 12V works without ANY changes.
The reduction can be made on a tiny stripboard or designed PCB.

Raising the 12V rails to 15 is not so easy. Parts changes may be needed. This determination will need to be made for every module.

The only time 12V rails make sense IMO is if you're going to use an established 12V format near exclusively. If not, choose 15V.

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Re: Which system/module to start building? (aiming at the bananas)

Post by Isaiah » Sun Mar 22, 2020 2:58 pm

KSS wrote:
Sat Mar 21, 2020 6:58 pm
Isaiah wrote:
Sat Mar 21, 2020 5:19 am
Keen to hear more about this if you’re able to share any information.
Was gonna be Synthplex, then Superbooth. With both those closed, the next 'synth release reveals' will likely be Behringer's plan to do a 'Billich SB' from their Willich headquarters at the original SB dates.

Still no decision yet whether to go before, during, or after that with it. CV crisis also a factor. But will be sure to let you know once decisions are made.
Thanks. I look forward to hearing more in the future.

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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Thu Mar 26, 2020 10:05 am

duff wrote:
Sun Mar 22, 2020 4:32 am
If you want banana’s and sDIY theN LW format stuff is great. An easy in is the Slightly Nasty line up with well thought out pcb and panel combinations.
https://www.slightlynasty.com
This looks cool indeed! Thanks for the suggestion.

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Re: Which system/module to start building? (aiming at the bananas)

Post by Parmesan » Thu Mar 26, 2020 10:13 am

KSS wrote:
Sun Mar 22, 2020 1:58 pm
When choosing rail voltage for a DIY format, consider this.
15V rails can be inexpensively reduced to 12V with 78L12 and 79L12 so that EVERY module designed for 12V works without ANY changes.
This makes sense. I think I'll build modules that are working both on 12V and 15V using the 12V supply I have now, but eventually will get/build a 15V supply and build everything around it.

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Re: Which system/module to start building? (aiming at the bananas)

Post by nrrrd » Thu Mar 26, 2020 2:34 pm

An off the wall choice would be to build some ciat-Lombardi, like a rollz 5. The schematics are widely available, as are PCBs based on the paper circuits.
You can also look into adding modulation. For rollz 5 you can add FM with a cv mixer, and other modulation using vactrols or lm13700 based voltage controlled resistors.

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