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Transistor voice modulation? Answered

Alright, i know now that there is a way to modulate your voice from putting signal in on the voltage pin of a transistor, and controlling it with a synth into the input voltage. But now, what is that effect? and what is a way to smooth out or get clean sounds from it? Any help is appreciated. Thank you. 


Of course in these days of digital audio workstation (DAW) software, the cheapest solution may be to do it in a computer. Websearching "vocoder plugin plug-in" finds a fair number of VST and similar tools, from free to fancy. Broading your search will find manymany other auto processing plugins.

Note that even professional-quality DAW software can be surprisingly affordable. One possible trick for further reducing that cost: If the manufacturer makes a low-cost "home studio" version, sometimes getting that and then upgrading to the top-of-the-line product is cheaper than buying their best immediately ... and you may find that the basic tool is quite sufficient for your needs.

Im more of an analog person but yes computers can be fun to play with.

Look for techniques like the "Ring modulator" - they were used to make the original Dalek voices on Dr. WHo. Various fans sites for the daleks have details on the voice changer.

If the goal is to modulate the voice with something, rather than modulate something with the voice, this is the right direction. See also the vocoder projects, which are another way of doing odd things with voice. See also the "talking guitar" effects, which feed the guitar's sound into the performer's mouth for formant processing.

The vocoder is basically what i am trying to accomplish. The talkbox i have already delved into.

See the vocoder instructable, then, or websearch "vocoder circuit" and see what else turns up. Though if you aren't familiar with ring modulation, that might also be worth investigating, depending on what effect you're trying to get.

Ring modulation, to my ears does not make sense. i played with it on a guitar and it did nothing except sound very pitch distorted....

Ring modulation works better with sounds that have fewer harmonics. You didn't specify guitar (though I suppose the icon could have been a hint).

If it isn't what you're looking for, and the usual filters and so on aren't doing what you want, then yeah, vocoder may be it.

Well guitar has sorta faded out. I went from piano, to guitar, to building guitars, to building guitar amplifiers, to building guitar effects, then to synthesizer. So now i am heavy into synth. And i want a vocal effect that is not the talkbox, that kind of got annoying. I love the vocoder on the Microkorg XL, but thats almost $500!!! So i set out to build my own something like that.

Yes. This is how you build a simple AM-transmitter. First build a little oscillator that puts out say... 100kHz . Then connect the power source to the oscillator to a transistors output (emitter or collector wire). Then connect a microphone to the 3rd wire of the transistor, the BASE. Now when you make sounds on the microphone... the voltage to the oscillator will change. This will "modulate" the 100kHz signal. That just means the oscillators output will follow the microphones signals. Building a transmitter is extremely easy. Building a reciever is a lot more involved.