Making a vocoder out of an equalizer

EQ's and vocoders have quite some things in common. It shouldn't be that hard to convert an equalizer to a vocoder, especially if the EQ has a spectrum analyzer.

My dad used to have an awesome EQ as part of his stereo setup, see if I can find that thing.

hm, I think it's time for me to register an account over at muff's

Edited July 28, 2013 by th555

i think vocoders are a bunch of bandpass filters and envelop followers.

Yes they are. And equalizers are a bunch of bandpass filters as well. And if you have a spectrum analyzer, there's your follower. But a digital/hybrid follower would be cool as well.

you need something to detect the frequencies of one source and allow the same frequencies at the exact same levels from another. I think an regular EQ is about a tenth of what you need although your shooting in the right direction.

here's a dude who made a vocoder solely in renoise. it's pretty impressive and you get a good idea what a vocoder does internally.
http://forum.renoise.com/index.php?/topic/23362-renoise-25-vocoder-using-only-internal-fx

i've heard about this being done in reason

Yeah, I could make an EQ in FL just now. Just basic stuff, really, but with cool results.

 

 

  On 7/28/2013 at 6:28 PM, soundwave said:

you need something to detect the frequencies of one source and allow the same frequencies at the exact same levels from another. I think an regular EQ is about a tenth of what you need although your shooting in the right direction.

What're these other nine tenths, then? The only thing that's missing is something to drive the filters, instead of the sliding potentiometers. This could be done with a frequency analyzer, It's no problem for the followers of a vocoder to be a bit slow, is it? It could also be done with another set of bandpass filters (I've seen some cheap double eq units) and some additional electronics.

 

IMO the real fun starts when you're having a microcontroller driving the bandpass filters. You could do some awesome glitchy/autotuney stuff.

Edited July 28, 2013 by th555

Just built a 5-band vocoder with basic FL ingredients. The amount of control you have in comparison to standard vocoder plugs is really amazing, I'll definitely be using this at some point :D

Edited July 28, 2013 by th555

you would need another set of eqs. then youd have to rig the analyzer to control the eqs. might only be really effective with bandpass filters tho

Edited July 29, 2013 by marf

Yes, you're right marf. What do you mean by this:

  On 7/29/2013 at 7:44 AM, marf said:

might only be really effective with bandpass filters tho

?

a set of bandpass filters perfectly divide up the spectrum. so you can recreate a sounds spectrum energy that way. standard EQ with its roll off and cross over might not sound anything like a vococder. I dont know, might sound interesting. Im not explaining it well enough. Im sure. thats all i know. you could write a book on it probably

Edited July 29, 2013 by marf

yep, that's the good old way..splitting up the spectrum via bandpass filters and forcing that on to the carrier via vcas..

 

http://www.analogue.org/network/vocoder.htm

 

nowadays it's all fft..stft

Edited July 29, 2013 by iococoi

  On 7/29/2013 at 5:23 PM, marf said:

a set of bandpass filters perfectly divide up the spectrum. so you can recreate a sounds spectrum energy that way. standard EQ with its roll off and cross over might not sound anything like a vococder. I dont know, might sound interesting. Im not explaining it well enough. Im sure. thats all i know. you could write a book on it probably

You explained it well, I get your point. I hadn't thought about roll-off and stuf like that, would be something to test before starting on a project like this. Could be tested in a DAW though.

 

  On 7/29/2013 at 6:14 PM, psn said:

Looks good! I suppose it is good, then :P Edited July 29, 2013 by th555

is there such a synth that uses one oscillator for each note along the audible spectrum? would be cool to have one of those and a mod matrix that can do FM, flow-stone me up one of those right quick.

  On 7/29/2013 at 7:42 PM, skibby said:

is there such a synth that uses one oscillator for each note along the audible spectrum? would be cool to have one of those and a mod matrix that can do FM, flow-stone me up one of those right quick.

There is an old analog polysynth that has a separate voice card for each note, if that's what you mean? I don't remember the name of it, but IIRC the dude was talking on his blog about making 40 monosynths out of those voice cards, or something.

 

And of course you could achieve it digitally, maybe sytrus will do the job.

Edited July 29, 2013 by th555

  On 7/29/2013 at 7:55 PM, th555 said:

 

  On 7/29/2013 at 7:42 PM, skibby said:

is there such a synth that uses one oscillator for each note along the audible spectrum? would be cool to have one of those and a mod matrix that can do FM, flow-stone me up one of those right quick.

There is an old analog polysynth that has a separate voice card for each note, if that's what you mean? I don't remember the name of it, but IIRC the dude was talking on his blog about making 40 monosynths out of those voice cards, or something.

 

 

pshh only 40?... im talking (checks the notes of the audible spectrum... cant find) ...

 

THIS MANY oscillators...

How do you make a smooth sound out of a tight bunch of oscs?

  On 7/29/2013 at 7:55 PM, th555 said:

 

  On 7/29/2013 at 7:42 PM, skibby said:

is there such a synth that uses one oscillator for each note along the audible spectrum? would be cool to have one of those and a mod matrix that can do FM, flow-stone me up one of those right quick.

There is an old analog polysynth that has a separate voice card for each note, if that's what you mean? I don't remember the name of it, but IIRC the dude was talking on his blog about making 40 monosynths out of those voice cards, or something.

 

And of course you could achieve it digitally, maybe sytrus will do the job.

 

Do you mean the PS-3300?

3osc per voice x 48 voices.

I think that's the one yeah. Was control logic really that hard, back then?

What do you mean?

Like assigning a new voice to a used one? The logic was the same but it hadn't been figured out very well.

Edited July 31, 2013 by DerWaschbar

Well I'm sure they were smart guys, and I'm sure they had a reason to use 40 boards instead of 10. I'm thinking they took the piano approach, which seems logical.