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Any ideas on how I can hoop up an old synth to a PC? Answered

I have this pretty old synth that has no midi out, just out for a speaker.

About the hookup, I know I can just hook it up to my PC's Microphone/Audio Input and record but that's not the point. What I want to do is hook it up to a program (like Reaper) and use the program's synths. So, just use it as a keyboard.

And from what I can('t) tell the output is something like square wave (also it can put out sine on the bass keys and i think some options have triangle waves.)

Also I have no idea what model this thing is, all I know that it was made by Vermona and it makes a pretty good sound.

It's completely analog.

Thanks in advance


If you can setup the synth to output a clean waveform (sine wave?) how about using a pitch-MIDI converter between the synth and your PC?

The other option would be to add a MIDI encoder but that would require tapping into the keying circuits. It can certainly be done but would require some knowlege of the circuitry.

I can set it to put out a clean square wave.

Actually that was my first thought, but I didn't think there was such a thing as pitch-MIDI.

Do you have any idea on how to make one or where to buy one, or should I get googlin'.

I know there is some software out there that will do it, here for example:


But that pre-supposes that you are in a Windows environment.

Here's a hardware project:


But your best bet is to spend some time with Google...

Forget it. For what you are trying to do, you need a digital signal. Unless you have MIDI, it will not work. An analog audio signal can't be easily converted into a MIDI signal.

Yeah, I figured as much when I looked a bit closer on the inside.

Heh. I still got Reaper. Managed to get it to sound almost like a piano through a MIC input. Besides I somehow made my guitar sound like drums so making this sound like something else shouldn't be that hard. (Should have thought of that before posting the question.....)

Anyway, thanks for the quick reply!

(Later on I might try detaching the keyboard and hooking it up to some sort of controller to get a midi out. But I still have some research to do.)

I sincerely doubt that the synth you showed here will ever be able to use MIDI... but who knows, you may find a way! (I believe that where there's a will there's a way.) :) Just be careful using that mic input... it normally isn't made to handle line level, it's made for mic level. You might fry your sound card if you aren't careful.

Nah, I would never hook up the amp directly to the sound card. I'm bypassing the added amp, and directly hooking it up to the synth out witch is not that powerful, but it's enough for the program.

I'm not talking about the amp, but there is a difference between mic and line level. Google it if you don't know the difference. I am 95% sure that your synth is line level and your mic input is mic level. It will not happen right away, but if you run line level into mic level long enough it will destroy your mic level equipment.

Won't plugin it in the Line Input solve the problem, or am I misunderstanding it again?

No, if you have a line input, then you should be fine. A lot of people try to put line level through the 1/8 in. mic jack on a computer, which can fry your sound card after awhile. I thought that's what you were trying to do. Some computers now days have a line level input, but most do not.

It depends on the computer. Desktops usually have bothMic and Line In while most laptops only have one input which is usually Mic. Some laptops have a utility that converts the Mic input to a Line In input. That would be found under the audio options (mixer).

As for MIDI, these days you would use a USB or FireWire interface to hook your MIDI compatible keyboard to the computer. Then you could use Reaper. My son recorded his guitar on his laptop (music interface) as analog and used Reaper to change it into "Space Electronica". Doesn't sound like a guitar at all. You can do that (analog input) in "real time" using ASIO4ALL, Mixcraft and Reaper. See this question for more info. Look at the bottom of the "best answer" thread.


I agree that it depends on the computer, however, I wouldn't say "most" desktops have line level inputs (at least in my part of the world... Maybe it's different in other parts of the world). From what I've seen, newer apple computers (both laptop and desktop) tend to have both, but although I hate to admit it, most Windows computers that I've seen only have mic level.

I did say "usually". I haven't been privy to those desktop models, though it has been two years since I bought one, and all the desktops I own have Line In and Mic. The laptops in my house are the opposite (except one Acer, and that was the reason I bought it). No idea about Apple - not my type, just because.

If you do go desktop, a good, separate, soundcard is recommended. This will come with all the ADC inputs you want.


*My favorite computer to record on is an old E-Machines with Win98SE. That is all it is now used for. Yeah, it uses older software, but it is great for raw tracks - clean and clear.

I wouldn't say "usually" in my area either. The last computers I bought were 1 year ago (laptop) and 3 years ago (desktop). But even though I don't buy a computer every day, I do keep up-to-date with the new ones. I currently do IT consulting, and less that a year ago, I did data recovery. Because of that, I see hundreds of computers every week. A few of them have line in jacks that came with the computer, but most of them don't. I agree that after market sound cards are a good way to go, but if you are doing recording, then an external XLR and 1/4 in. Input is another good product to buy. M-Audio makes some nice ones. For recording, there is nothing wrong with using old software as long as it works. Reason being, you can always transfer the recorded file to another computer with newer software for editing. :)

In that case, I will defer to you on the new hardware. I agree about the ext. soundcards and ext. "input boxes". My son uses an M-Audio for his input (now) and it is just as clear on his laptop as it was through my own hand-built stereo preamp (which is d**n quiet). More noise from the old stereo used for monitor purposes than from either computer.

Anyway, if TOC can attenuate the speaker output enough he can put it through a computer in one of the ways described above. He just needs to be careful of the levels and the AC coupling. How that is done is up to him and only he knows his level of technical prowess and financial ability. There are literally thousands of useable schematics on the web to choose from.


One thing I have to say is that I completely agree with the ext. soundcards. Some people even say "You haven't heard quality until you've installed an ext. soundcard" that is if it's quality material, some PCs have pretty decent internal sound cards.

Also I've been using Reaper with ASIO4ALL for some time now and I can say that the sound I managed to get out was pretty good (excluding the factor that my sound card is barely working.)
About the Line Input, most (if not all) PCs I've seen here have it. Of course not all laptops do.

Me system. The PC I'm currently using is a HP Vectra VL420 (with a little upgrade). It may not be new, but it gets the job done and that's all that matters (for now.). It has a internal sound card that produces pretty good output quality, as well as input quality. Of course if the sound card wasn't broken the quality would be pretty awesome. I was thinking of getting a new sound card, as this one's left output stopped working for some unknown reason, and some buzzing developed (as if there was no grounding, but i (temp) fixed that).
I see you say M-Audio has good audio cards, I'll have to check em out.
(Also lol 420).

btw Thanks for all the info!! (and sorry if there are any mistakes in the text)

M-Audio doesn't really have an audio output card that I know of, but they're inputs are considered to be the recording industry standard. :)

Yeah, I saw that when I opened their site. I might get one of their input devices, but currently I'm not looking for something that has that high quality (besides for now my integrated card does the job, but who knows one day I might need something like that :) ).

Also when I combined this synth with a HQ pre-amp I made, the output had really high quality (of course using the best output amp and speakers i had) (almost forgot, the output is from another audio card because this one had a big problem with the output. The other card doesn't seem have Line input nor MIC, weird.)

So for now I'm sticking to Reaper and the Line In on my integrated card.
(might even upload a demo later :D )

Oh... Forgot to mention apple in my comment below: I totally agree with you about apple: not my type either, although I can back my claims up with more than "just because". There's nothing wrong with "just because" in my opinion, but try to tell that to a Mac lover! ;) If I had my way, I would never have seen a Mac in my life, but in my previous job, I had to be able to recover data from any system.

Also thanks for the heads up I had no idea it was like that.

No problem! :)

So basically, a keyboard-midi interface ??? Ignoring the sound qualities ?