[sdiy] LFO control - frequency or time?

[nicolas]

Frequency versus time thinking also often needs to be in the units BPM and notes or bars.  But the answer comes out similar although there is some overlap.  BPM related frequencies are typically ~ 0.3 Hz or faster.  One pulse per bar is 0.3-0.6 Hz.  One pulse per quarter note is around 2Hz, eighth notes around 4Hz, etc.  On the other hand bars, quarter notes, eighths, sixteenths are units of time, typically around 2-3s per bar, with a sixteenth down around 0.1-0.2 seconds.

So I think there is a real overlap region from say 0.1-4s or 0.2-10Hz where it sometimes best to think one way and sometimes the other.

Cheers,
Nicolas

--- On Tue, 2/6/09, Tom Wiltshire <tom at electricdruid.net> wrote:

> From: Tom Wiltshire <tom at electricdruid.net>
> Subject: Re: [sdiy] LFO control - frequency or time?
> To: "Veronica Merryfield" <veronica.merryfield at shaw.ca>
> Cc: "sdiy DIY" <synth-diy at dropmix.xs4all.nl>
> Received: Tuesday, 2 June, 2009, 11:47 AM
> I absolutely agree, Veronica. Above
> 1Hz, frequency makes sense (cycles per second), whereas
> below it time (seconds per cycle) is more obvious.
> 
> T.
> 
> On 2 Jun 2009, at 00:34, Veronica Merryfield wrote:
> 
> > I think the tipping point is 1hz.
> > 
> > Above this, one probably wants to quote frequency and
> below this, time.
> > 
> > Veronica
> > 
> > On 1-Jun-09, at 3:21 PM, Neil Johnson wrote:
> > 
> >> Hi all,
> >> 
> >> Ok, here's a good point for discussion:
> >> 
> >> In my latest design on the bench I have a VCLFO
> which so far has a range of about 125us (8kHz) to roughly
> 120s (8mHz).  I think it could go even slower, but so
> far I don't have the patience to sit there with an
> hour-glass and time it.
> >> 
> >> So I got to thinking: for a CONTROL oscillator is
> it more useful to think, and program/use/set/twiddle, in
> terms of TIME (how long a cycle takes) or use the same
> concept of FREQUENCY as for the audio oscillators?
> >> 
> >> I open the debate with the view that it should the
> TIME - for a slowly-varying control signal I think it makes
> more sense to think in terms of how long a modulating cycle
> will take.  Saying    
> >>     "I want a slowly varying
> modulation over 54 seconds"
> >> seems more natural and intuitive than saying
> >>     "I want a slowly varying
> modulation rate of 18.5mHz"
> >> 
> >> Comments welcome!
> >> 
> >> Cheers,
> >> Neil
> >> --
> >> http://www.njohnson.co.uk
> >> 
> >> 
> >> 
> >> _______________________________________________
> >> Synth-diy mailing list
> >> Synth-diy at dropmix.xs4all.nl
> >> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
> > 
> > _______________________________________________
> > Synth-diy mailing list
> > Synth-diy at dropmix.xs4all.nl
> > http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
> > 
> 
> 
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
> 


      Need a Holiday? Win a $10,000 Holiday of your choice. Enter now.http://us.lrd.yahoo.com/_ylc=X3oDMTJxN2x2ZmNpBF9zAzIwMjM2MTY2MTMEdG1fZG1lY2gDVGV4dCBMaW5rBHRtX2xuawNVMTEwMzk3NwR0bV9uZXQDWWFob28hBHRtX3BvcwN0YWdsaW5lBHRtX3BwdHkDYXVueg--/SIG=14600t3ni/**http%3A//au.rd.yahoo.com/mail/tagline/creativeholidays/*http%3A//au.docs.yahoo.com/homepageset/%3Fp1=other%26p2=au%26p3=mailtagline