[sdiy] Generating a large number of CV outputs

[Gordonjcp]

On Thu, Dec 14, 2023 at 03:53:39PM +0000, Mike Bryant wrote:
> If by 'continuous' you mean DC, then there is an image before filtering - at the sampling rate :-)
> 

No. If you've got a DC output from a DAC, it's just that - DC. There's no change in level. You're writing the same value to it over and over, and it does not change.

The output from a DAC is continuous. It does not have steps. It has steep slopes, but not steps. Even then, that's not going to allow the sample rate to leak out particularly. If you pick a pathological case where your DAC is swinging fully positive for one sample time and fully negative the next, you'll get a signal at half the sample rate. Even though that's a squarewave right at Nyquist, it still won't alias, because the harmonics are being generated *after* the discrete-time part.

So I'm having a hard time seeing where these images could come from, or how you'd ever detect them. You definitely couldn't hear them.

-- 
Gordonjcp