[sdiy] voice recorder

[mikko.a.helin at nokia.com]

Ups, forget this: AVR335: Digital Sound Recorder with AVR and Serial
DataFlash.

http://www.atmel.com/atmel/acrobat/doc1456.pdf

You'll have a lot more control on recorder using this app note as basis. If
you want to pitch the samples it's a whole different thing. I strongly
recommend studying the VST plugin architechture first and trying your ideas
on software before building anything. Getting alias free sample playback is
difficult and needs considerable amounts of processing power (though simple
linear interpolation works and can be implemented even on AVR chips).

-Mikko

> -----Original Message-----
> From: ext ElmacacoX at aol.com [mailto:ElmacacoX at aol.com]
> Sent: 25. October 2001 1:26
> To: krooshof at xs4all.nl; synth-diy at dropmix.xs4all.nl
> Subject: Re: [sdiy] voice recorder
> 
> 
> while at radioshack today I saw the ISD1000A chip, some 
> marked $17, and 
> another marked $9.95, so I grabbed it, and it ended up being 
> only $5.38.
> 
> I just read the app notes and it seems pretty simple to 
> implament into a 20 
> second sample jammie module.  no need to even mess with the 
> address points 
> since in operation mode you can move the playback from sample 
> to sample (you 
> can sample more than once within the twenty seconds, although 
> you can only 
> loop the sample that begins at the beginning, unless you add external 
> circuitry).  you also can only loop if you don't overload the 
> memory, so less 
> than 20 seconds.
> 
> I guess for wavetable modules and whatnot based on this you'd 
> need extensive 
> logic on the address pins.  not really what i am going for.  
> 
> the only thing that seems tricky to me is matching up the 
> impedeances for use 
> with my synths and stuff, and also attenuating the input 
> signal or something 
> since it can only have 50mV at the analog input. and also 
> maybe someway to 
> mess with the internal sample clock, it has a clock input, 
> but the app notes 
> don't go into it.
> 
> This sounds like too much fun!
> 
> Ed
>