[sdiy] They aren't sawtooths, they're ramps

[Kyle Stephens]

"YOU MEAN THE SIGMOID???? :PPP"

Colloquially know as "Stephensine" ;)


_Kyle (asked the list a while back what a saw/ramp through a sine shaper would sound like) Stephens


PS: Aaron Lanterman halfway suggested this - I tried running a guitar (aka roughly sine) through the Thomas Henry sine shaper, though my gain stage was pretty noisy as what I happened to have breadboarded up at the time was another effect in progress - got some interesting noises and a compression effect at some settings... More tweaking that latter.

--- On Wed, 11/4/09, cheater cheater <cheater00 at gmail.com> wrote:

> From: cheater cheater <cheater00 at gmail.com>
> Subject: Re: [sdiy] They aren't sawtooths, they're ramps
> To: "David G. Dixon" <dixon at interchange.ubc.ca>
> Cc: synth-diy at dropmix.xs4all.nl
> Date: Wednesday, November 4, 2009, 1:30 PM
> > Waveforms derived from
> relaxation oscillators definitely do not fit the
> > bill, and therefore should not be called "sawtooth",
> any more than some
> > random "rounded" waveform should be called "sine".
> >
> 
> YOU MEAN THE SIGMOID???? :PPP
> 
> On Wed, Nov 4, 2009 at 20:30, David G. Dixon <dixon at interchange.ubc.ca>
> wrote:
> >> snip >
> >> > "Ramp" refers to the ramping part of the
> sawtooth wave, but could also
> >> > refer to waveforms where the ramp is an
> important part of a waveform
> >> > that's not really a sawtooth wave.  For
> example; a wave that starts
> >> > low, ramps up, holds there for a bit, and
> then resets.
> >> >
> >> > Relaxation oscillators are what they are,
> they don't define the
> >> > sawtooth wave.
> >
> > I tend to call it a sawtooth when it ramps downward,
> and a ramp when it
> > ramps upward.  However, it seems to me that we should
> reserve the term
> > "sawtooth" for either upward or downward ramps which
> are linear; i.e., those
> > which are generated by a carefully designed VCO
> feeding a fixed current to
> > an integrator with one end of the cap pinned to
> virtual ground, and which
> > can be counted upon to contain both even and odd
> harmonics with amplitudes
> > inverse to their harmonic number.  At least, in synth
> circles, I think we
> > should make this distinction.
> >
> > Waveforms derived from relaxation oscillators
> definitely do not fit the
> > bill, and therefore should not be called "sawtooth",
> any more than some
> > random "rounded" waveform should be called "sine".
> >
> >
> 
> _______________________________________________
> Synth-diy mailing list
> Synth-diy at dropmix.xs4all.nl
> http://dropmix.xs4all.nl/mailman/listinfo/synth-diy
>