Re: [Audacity-quality] Delay effect - what do we want to do about it?

[Gale A. <ga...@au...>]

| From Steve the Fiddle <ste...@gm...> 
| Tue, 24 Jul 2012 03:57:29 +0100
| Subject: [Audacity-quality] Delay effect - what do we want to do about it?
> On 23 July 2012 21:34, Gale Andrews <ga...@au...> wrote:
> >
> > | From Steve the Fiddle <ste...@gm...>
> > | Sun, 22 Jul 2012 22:43:24 +0100
> > | Subject: [Audacity-quality] Delay effect - what do we want to do about it?
> >> I think we're probably guessing at "main use cases".
> >> Perhaps the reason no-one complains about the change pitch effect is
> >> because nobody uses it.
> >
> > You could test that out by removing it rather than offering two
> > different pitch effects. I see no need to remove it - I've heard
> > a few pop songs that seem to use a delay with pitch drop.
> 
> I'd like to try removing it.
> This would at least get the other bug fixes in place and it would mean
> that we are not compromising on quality in the shipped plug-ins.
> 
> Depending on user feedback we could easily put it back in. In fact I
> could leave the (bug fixed version) code in place and just commented
> out while we see what user response there is (if any).

Well, you could make a mockup like that. It might still be acceptable
to uncomment the pitch controls.


> > Perhaps people who use the current pitch/speed effect don't
> > care about the deficiencies.
> >
> > My only concern was in making clear the pitch effects are one
> > tone maximum (which seems most clearly done by having them
> > separate) and that the Nyquist pitch change should not be
> > default (because the delay you get is never what you asked for).
> 
> In the shipped version the user is not getting what they asked for.
> When Pitch Change is used the delay time is only what was asked for at
> the moment that each echo starts. Beyond the first sample of each echo
> the delay time progressively shifts either longer (for lower pitch) or
> shorter (for raised pitch). In the case of raised pitch, after a few
> seconds the "delayed" signal occurs "before" the dry signal.

Yes I understand that, if you have a longish selection. Changing the 
default should not be done lightly especially if the new option you 
are making the default is equally strange. 


> Perhaps call the old pitch change option "Pitch/Tempo" and the Nyquist
> pitch shift "LQ Pitch Shift"? 

As long as the old pitch change option still mentions "pitch", that's
fine by me.   


> >> If I wanted to use delay with pitch shift I would find the current
> >> version to be unacceptable because it does not maintain the correct
> >> delay time. However, that said, I'd probably not complain about it but
> >> just accept that it didn't do what I wanted and create the correct
> >> effect by manually making several delayed duplicate tracks and use the
> >> Sliding Time Scale / Pitch Shift effect on them.
> >>
> >> I can't imagine the current delay effect being accepted into Audacity
> >> if it were submitted now. Perhaps we should completely rethink the
> >> delay effect and replace it with something more "professional". How
> >> about a multi-tap feedback delay?
> >> http://audacity.sourceforge.net/manual-1.2/effects_delay.html
> >
> > Can you do all of that in Nyquist?
> 
> With some constraints, yes.
> 
> The main constraint is the user interface. For a multi-tap delay the
> number of controls goes up with each additional tap. At least 2
> additional controls are required for each additional tap (a "full
> featured" multi-tap delay would have many more).
> 
> Adding Eq to the feedback loop can be done, but would slow down
> processing time considerably. It would however be possible to have a
> "fast" mode by providing an option to disable the Eq.
> 
> A single tap delay with feedback could provide greater control and
> could be applied multiple times to achieve a multi-tap effect.

Sounds like the last sentence is about as far as you would want
to go with a Nyquist effect? 





Gale