JH's VCO, wavetable source

[John Speth]

On Monday, July 05, 1999 4:58 PM, Grant Richter [SMTP:grichter at execpc.com] 
wrote:
> >
> > > I have to point out that the most elegant solution to
> > > wavetable generators is an analog to digital converter.
> >
> > ...I don't think so. I personally don't like the idea of
> > converting an analogue signal into digital domain and
> > back.
>
> Well, using a counter is certainly converting it into the digital
> domain. Using a waveform stored in EPROM is certainly
> digital domain.

I'm assuming the "elegant solution" means that a ramp will drive an ADC 
which will index into a ROM table whose output will go to a DAC and you get 
a ROM defined waveform with the same frequency as the original ramp. 
 Right?

If my assumption is right then I have a question...

I have yet to see *the perfect* ramp and I can't see that you can 
practically get one.  Every one I've seen (and that isn't a lot) has little 
imperfections at the peaks and you have to deal with that finite switch 
time too.  How do you deal with these problems?


John Speth
Object Engineering, Inc
mailto:johns at oei.com