Change Slower element maximum value?

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Kewl
KVRist
211 posts since 11 Apr, 2007 from Montreal, Canada

Post Thu Jul 23, 2015 1:52 pm

In SB1, what is the "Change Slower" element maximum value?

makira
KVRist
158 posts since 25 Mar, 2005

Re: Change Slower element maximum value?

Post Sat Jul 25, 2015 12:28 am

There is, in theory, no maximum. In practice, you'll hit the limit due to the precision of the floating point number representations.

Kewl
KVRist
211 posts since 11 Apr, 2007 from Montreal, Canada

Re: Change Slower element maximum value?

Post Sun Jul 26, 2015 5:26 am

OK, thanks.

If I wanted to construct from scratch a "change slower" circuit, what would be needed?

dtpietrzak
KVRist
45 posts since 16 Feb, 2012 from Indiana

Re: Change Slower element maximum value?

Post Sun Jul 26, 2015 8:12 pm

I think it can be done with an envelope detector. Just set the attack and release to the same values. http://musicdsp.org/archive.php?classid=2#97 This is an algorithm for an envelope detector. There's a few of 'em here.

makira
KVRist
158 posts since 25 Mar, 2005

Re: Change Slower element maximum value?

Post Sun Jul 26, 2015 10:35 pm

The algorithm is simple:
sr is sample rate, t is speed in milliseconds, i is input sample, o is output sample, c is a derived coefficient, and s is a state value.

Initialisation:
s = 0
c = 0.01**(1000 / (t * sr)) (where ** is the power operator)

Application:
s = c*s + (1-c)*i
o = s

You can also look at the smoother circuit in SBv2 which does the same thing, except it initiatize s to the first sample it sees.

Kewl
KVRist
211 posts since 11 Apr, 2007 from Montreal, Canada

Re: Change Slower element maximum value?

Post Sun Aug 02, 2015 4:10 am

OK, thanks. It works, but it's too slow. The feedback element maybe?
Capture d’écran 2015-08-02 à 14.56.54.png
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makira
KVRist
158 posts since 25 Mar, 2005

Re: Change Slower element maximum value?

Post Mon Aug 10, 2015 7:04 am

Can't implement it manually in SBv1, since the feedback element delays the signal a full block instead of a single sample.

Kewl
KVRist
211 posts since 11 Apr, 2007 from Montreal, Canada

Re: Change Slower element maximum value?

Post Mon Aug 10, 2015 7:17 am

Ah, OK... Thanks.

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