Has anyone here created their own hardware synths?

[VitaminD]

Just wondering...

I've been watching some youtube videos (perhaps too many ) and getting inspired by all the interesting gear people are making...

if anyone here has direct experience with building hardware synths or effects.. I'd be interesting in knowing how much money and time it takes to get a clean, final product. (or at least how long it took you)

I'm NOT an electrical engineer, but am not afraid to get my hands dirty with the electronics.. that said.. if it would require an EE degree (or similar experience) then of course I'd like to know that before getting in over my head.

[ouroboros]

tomg sells hardware parts: he makes hardware and modular stuff at electronics 4 musicians. Just from looking at some plans I've seen, I imagine you could do it quite competently.

[deastman]

Tom is the man! I've built a few of my own modules, as well as some PAIA kits. I intend to do a lot more of it after my kids are older and I have the time...

[aaastronomer]

a whole hardware synth, like say, a poly evolver keyboard? er, well...no...but, i am in the process of designing one!

[VitaminD]

cool

I've looked at some of the PAIA kits and the midibox DYIs... the PAIA fatman seems relatively inexpensive and interesting to me..

I just wish they'd have a preview of the assembly manual supplement so one could judge the level of difficulty... I'd practically need something that said 'solder resistor R2 to PCB block A' or something like that not 'here is the diagram, have fun'

[aciddose]

i've designed and built several modules and a fair number of pieces of gear over time. i've salvaged keyboards from electric organs and built them into cv boards, i've repaired and modified a few synthesizers over time.

so far, i've spent five years and several thousand dollars on test equipment, components and tools. i've never taken any courses, although for the basic stuff you really dont need to. if you're interested in designing high quality equipment and creating your own designs with out a lot of trial and error, i'd bet that courses would help. that said, trial and error works fine for me.

what i'd recommend you do first is build a psu. afterward, get used to creating your own cabinets, panels, racks, and woodwork. put the psu into a good box you've built and connect it to a bus. after you've got that down, you're ready to start building modules.

i'd really advise against trying to build any modules before you've got the experience building your own psu and figuring out how to get everything working well. i made that mistake and nothing i built ever worked really well until i found out how important it is to have everything really modularized.

let's assume you just want to build a psu and you've already got stuff like a drill press, other basic metal working tools and access to supplies. you're going to need a transformer, fuses, fuse holders, full-wave rectifier, regulators, capacitors, some kind of connectors like molex, some enclosure either you've built yourself or bought, either plain copperless pcb or the whole photo development and etching stuff, a dremel, solder, flux.. once you understand how this stuff works actually doing the psu is easy.

you need to learn a lot of stuff like voltage/amperage/wattage, resistance/capacitance/inductance.. all the functions and rules which apply. for example you need to know that if you're using a 5:1 transformer at 1amp, you actually need a 200ma fuse on the 120v side - you shouldnt attempt to build anything until you understand all the rules that come into play.

if you do not want to do your own designs and instead want to just assemble the kits out there, it still helps to have all the knowledge. otherwise you'll be totally lost the first time you run into any sort of problem.

building your own electronics can be like writing your own software. doing it yourself can be cheaper if your time is worthless. once you get all the equipment though, like function generators, oscilloscopes, logic probes, curve tracer, component testers, a dmm, a good soldering iron/"station", uv lamp, etching tank.. it isnt quite so cheap anymore.

the bright side though is you can design your own equipment and get things working the way you want: http://xhip.cjb.net/temp/public/sawers.mp3 http://xhip.cjb.net/temp/public/tuning_is_important.mp3

however, if you're going to build synthesizers i hope you're also going to use them, because for a guy like me who isnt all that great of a composer it kind of sucks. not that i regret spending the time, but like any hobby it can become a hole in the ground where you keep tossing money, on and on.

if you're interested in saving money, here is a simple list of expenses that should help:
in order of most expensive to least:
- equipment
- sockets/connectors, pots, knobs
- panels/enclosures
- pcbs
- components

so, first thing you're going to need to realize is that to get started it requires a major investment in both time and money for equipment. also, assuming you're not going into business selling synthesizers or something, you're not going to make the money back in savings, ever. it'll be more expensive over-all.

second, the most expensive stuff is always the stuff you see up front - the sockets, patch cables, pots/knobs, panels and racks or enclosures.

third will be the boards, pcbs. they will be very expensive to buy in raw form, and all the stuff needed to produce the finished pcbs with traces will cost a lot too. it can actually be cheaper to get somebody else to make the pcbs for you.

fourth will be the components, which really dont cost anything. other than major stuff like transformers, and capacitors at times, components are relatively zero cost.

[deastman]

cool

I've looked at some of the PAIA kits and the midibox DYIs... the PAIA fatman seems relatively inexpensive and interesting to me..

I just wish they'd have a preview of the assembly manual supplement so one could judge the level of difficulty... I'd practically need something that said 'solder resistor R2 to PCB block A' or something like that not 'here is the diagram, have fun'

That is basically the way PAIA assembly manuals read. Trust me, way back in high school I successfully built a PAIA vocoder and power supply, with absolutely no knowledge of electronics. I wouldn't recommend the vocoder as a first project, because there are about a billion jumper wires you have to connect... kind of a messy design. My friend has a Fatman, and it actually sounds pretty good, in a dirty sort of way.

[deastman]

In response to a few things Aciddose said...

That all sounds correct if you are actually planning to build a full-fledged synth from scratch. You seem to be describing a MAJOR development effort, rather than the sorts of projects a beginner would be likely to tackle.

If you are building from kits, all you really need is a soldering iron, solder, a cheap solder sucker, and a cheap multimeter. You could also pick up a used oscilloscope, or get a PC-based one fairly cheap, if you felt so inclined.

I would strongly discourage building your own PSU. Getting reliable power is critical, and everything which follows will depend upon it. I would recommend buying a commercial PSU from an electronics store (not Radio Shack). I found an excellent, brand new one at a local electronics surplus store for $20.

I've mostly built modules to expand my existing Doepfer modular system. Dealing with small circuits is much easier than building an entire synth all at once. Just build a resonant lowpass filter, for example. These circuits are usually small enough to fit on a small piece of pre-drilled prototyping PCB(available at Radio Shack and elsewhere), avoiding the headaches of trying to etch your own PCBs or the expense of having someone else do them. Obviously if you were going to build a large polysynth or go into commercial production, that would be a different story.

[Meffy]

Yeah, but it was in the late 1960s, practically prehistory from a hobby electronics standpoint. All discrete (no ICs), of course. First solid-state project I ever took on, so I had to learn to solder more quickly. Built on breadboard -- not perforated phenolic, but actual wooden boards with screws driven in to hold solder tabs. Patch connections were via Fahnestock clips and bare wires. They had to be pretty short.

I worked from Bob Moog's articles in Radio-Electronics or Popular Electronics (I forget which) but had to substitute a lot because I was even poorer then than now, and had few sources for parts. Nearest Radio Shack was sixty miles away. Never did get the 901 VCO (the all-in-one version, not the kind with separate A driver and B osc modules) to track frequency CV over more than an octave and a half before it went WAY off. At the time I thought it was all my fault but have since learned that the original 901 had a good deal of this problem even without my amateurish munging.

Took me a couple years to build a pawful of modules... but I was a kit who had to save up allowance money and such. I'm an EE now but at the time was a crummy 7th-grade cadet with far more ambition than sense. Now I have a little sense but not much ambition. Funny how that works.

My advice: go modular and build it piecemeal. That way you'll have plenty of intermediate goals, and you can start playing music after you've got a VCO, VCA, VCF, and some kind of trig/CV generator.

[aciddose]

"to track frequency CV over more than an octave and a half before it went WAY off"

didnt you read the part about matching the npn pair in the expo current source?
that is the problem with a lot of projects, articles, etc. they leave our critical information and so building following instructions can mean that if you run into any problem you'll have no way out. that sounds like the result of unmatched transistors in the current source though - either that or you used ceramic capacitors and/or didnt worry about slew rates in the integrator and comparator.

when i suggested building a psu, that was because if you want to build "synths" rather than have a set of loose modules laying around on prototyping boards you'll have to build/buy a lot more than one psu over time. getting a clean linear supply isnt that hard through. if you want to have exact voltages it's pretty much required that you build your own for a modular too, unless you want to spend a lot of cash on it. a cheap psu you can buy is good enough for bench testing, but you really need two main psus and a dirty psu for logic modules for a decent sized synth. oscillators, lfos and etc go on psu 1. filters and amplifiers go on psu 2. dividers and sequencers go on the dirty psu. most of the cheaper psus you can buy will be switching psus and the noise level will be quite high compared to a linear psu. if you buy a switching psu you should probably put some linear regulation afterward as well - but then you'll need a switching psu with a voltage out of +-25v or so. my problem was all my hardware runs off +-15v linear, and the only supplies i can ever find are +-12+5 switching.

ah, and this business of "linear vs. switching", "12v vs. 15v", those are things you'll need to learn before you even buy a psu if that is what you're going to do.

with 15v supplies your system probably will use peak voltages of 10v, while with a 12v supply you'll need to use either 7.5v or 5v. this is a problem if you're interfacing to other gear since the standard is 10vpp for cv signals, thanks to moog.

[VitaminD]

Thanks Guys

Don't worry though, I'm not going to build a synth from scratch anytime soon maybe in a decade if I'm still into building.. but at the moment I was considering a kit (like the ones from PAiA for example) to learn a bit from.. get my feet wet (so to speak) ..they come with the power supply anyways..

I'm glad to hear the PAiA kits at least are easy enough to understand/build.. I might really try the fatman first.. I like the dirtie sound

I've been dreaming (w/o any knowledge of if this is possible) of getting a cheap (possibly broken) keyboard/synth, gutting the shell (but keeping the keys), and plopping in the internals from some of these kits, basically reusing the keys... though I'll analyze the feasibility of this later.. after I've built kit device or two first

Thanks again.. very good information here.. I learned a few things that I wouldn't have considered too

[Meffy]

The keyboards of most modern synths are going to be digital -- just a set of switch closures, which you deal with however you want. Old-school monophonic analogs are going to want, at a minimum, a gate signal (note on/note off) and a control voltage, which probably means adding a loooong resistor divider along the keyboard. Might work, might not. Subtleties like velocity won't be easy to get across (impossible, I'd think, without some digital jiggery-pokery in the path... but I don't know every trick either.)

[Chuck E. Jesus]

i was looking at the "Cat Girl Synth" site, and there looked to be some useful mods and circuit boards to build them...i also have a Doepfer setup, and i'm pretty sure i could put some of those together, and rig them up to eurorack blank panels...not too sure about the power requirements though, haven't looked into it enough...the only things i've done recently is add some patch points to my Doepfer to use my Universal Vactrol mod along with an old analog delay pedal for the same...also got a bit of confidence to tackle calibration and minor repair of my older analog stuff...i must say, i'm envious of those with real electronics knowledge, i've read as much as i could, but it still seems to be somewhat of a puzzle i never found the rosetta stone for...my highschool cancelling the electronics shop courses due to the teacher quitting didn't help :baby crying to mama:

[deastman]

ah, and this business of "linear vs. switching", "12v vs. 15v", those are things you'll need to learn before you even buy a psu if that is what you're going to do.

The power supply I bought for $20 is a high-quality 15v linear supply. I can't quite recall the brand name but I'll post it when I get the chance. I suppose these might be hard to find in some places... its pretty easy when you live in Silicon Valley.

[m0j0byrd]

If really interested in building hardware synths ya'll gotta checkout:

http://www.ucapps.de (includes upcoming 3rd gen SID)
http://www.yusynth.net/Modular/index.html
http://www.musicfromouterspace.com/
http://electro-music.com/forum/forum-112.html

and for Thomas Henry designs:
http://electro-music.com/forum/forum-148.html