[PD] Smooth looping

[Frank Barknecht]

Hi,

not related to the thread on smoother audio in Pd, I am struggling with doing a smooth
loop player for data stored in tables. 

One building block for this is attached: It is a simple tabread4~ lookup that
should loop over a configurable section of a table and play it back with various frequencies.
As you'll easily see, I use a 

  [phasor~]
  |
  [*~ loopsize]
  |
  [+~ loopstart]
  |
  [tabread4~ table] 

idiom here. Now I would like to avoid enveloping the rewind sections, so I
built an elaborate mechanism to set the loop points as good as possible by
hand. Test sections let you load a sample or try to find the smooth loop points
inside of a sine-wave table graphically.

Now my problem is, that even when I have found a nice and smooth sounding loop
section, as soon as I start to change the frequency played (with the "pd
transpose" things), the sound gets very distorted. 

I'm puzzled: Shouldn't the tabread4~ interpolate correctly in this case?  Any
help or explanation is appreciated. (Except anything involving crossfades: I
know I could do that and I guess I also know how.)

Ciao
-- 
 Frank Barknecht            Do You RjDj.me?          _ ______footils.org__
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