Re: Voice to MIDI thru voc proc and guitar synth?

[andy butler <akbutler@tiscali.co.uk>]

mech@m3ch.net wrote:
> At 6:34 PM -0400 3/17/08, music@carlsonarts.com wrote:
>> I want to use my voice as a MIDI controller (i've always been one to 
>push the envelope, so to speak).  
>> I know, I could use a vocoder, but that limits to the presets 
>available, usually.  I want to be able 
>> to control any MIDI instrument that is out there with my voice, and not 
>rely solely on the vocoder 
>> patches that are available.
> 
> You might try looking into the Yamaha G-50 Guitar-to-MIDI converter.  
>Yeah, it's primarily for use with a 
> guitar and a 13-pin divided pickup, but there is also a single 1/4" 
>input jack on the front panel.  
> Ostensibly, it's designed so that you can use this for pitch-to-MIDI 
>conversion with a horn/sax/whatever.  
> However, I don't know why you couldn't try using it with voice as well.  
>You might even consider using an EQ 
> on the input (between the mic and the G-50) in order to maximize the 
>pitch-detection and tracking, as well.
> 
> Not sure how well it works with the front-panel input, but the G-50 is 
>widely considered to have the best 
> MIDI conversion and tracking when using Roland "GK"-type magnetic 
>pickups.  Given that pedigree, I wouldn't 
> think working on a single monophonic input would be too shabby.
> 
> You can usually find them on the 'bay for around two bills these days.
> 

The Yamaha G-50 front panel input works well with guitar, I assume it's 
just a way of accessing the guitar specific software without having to use 
a hex p/u.
However, guitar in many ways is a hard instrument to pitch detect, as the 
waveform goes through some interesting cyclic changes, so if it pitch 
tracks guitar, it should track anything.

The technology in the G-50 is licensed from Axon, it's the best pitch 
detection you can get.

One problem is that a guitar has a definite attack at the start of the 
note, allowing a trigger point for the midi note to be easily selected. So 
any audio to midi converter is possibly going to have trouble deciding 
when to actually send a note-On if presented with a voice signal, which 
can have a very even dynamic.

Any device that just converts audio to Note-On will never work well, it 
also needs to produce midi pitch bend information. Without the pitch bend, 
there's no way to correct a wrongly identified note, and there's no way to 
track anything legato.
The G-50 has this function, as do the Axon and Roland products, but I've 
no idea whether some the other solutions mentioned here can do this. 

andy butler