Re: [LAD] denormals

Fons Adriaensen wrote:
> On Fri, Aug 28, 2009 at 07:34:20PM +1000, cal wrote:
>
>> As in a small DC bias, how small is a "very very very small constant number"?
>
> I use something like 1e-20f, which is 400dB below normal levels
> and unlikely to cause any problem.
>
> The trick is to apply it at the right place. In almost all
> cases where denormals turn up it is the result of having
> some delay line with feedback, causing values to decay
> exponentially when there is no signal. The right place
> to insert the DC bias is at the input of the delay line.
that's helpful, thanks!

> A 'delay line' can be as simple as
>
> for ()
> {
> ...
> x = x * 0.9f;
> ...
> }
>
> where x is a one-element delay, so this would
> become
>
> x = x * 0.9f + 1e-20f;
and that too!

cheers, and thanks.

_______________________________________________
Linux-audio-dev mailing list
Linux-audio-dev@email-addr-hidden
http://lists.linuxaudio.org/mailman/listinfo/linux-audio-dev
Received on Fri Aug 28 16:15:03 2009