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Subject: Re: Phaser Modulation

From: JWBarlow@...
Date: 1999-12-02

In a message dated 12/1/99 7:34:20 AM, Ken.Tkacs@... writes:

>I remember reading an essay a long time ago about modulating
>frequency-domain devices. It claimed that a sinusoidal LFO was a
>less-than-ideal source for modulation because of the log nature of the
>frequency/pitch spectrum. A sin (or triangle, if we're being cheap) tends
>to
>"rush" through the lower frequencies and take "too long" to sweep high,
>giving a vertically off-balance cycling.

Thanks Ken! This was the point I was trying to make (not build in 2 MOTM 320s
into the Phaser). But I also think that other LFO waveshapes produce
identifiable (and popular) types of sweeps. For example, any LDR based phaser
would (presumably) have a characteristic type of sweep that might be worth
incorporating. If these could be implemented by VC (possibly by adding just a
few components for say $20), all the better! If not, oh well.

>This article claimed that the best way to modulate these kinds of devices
>was a negative-cycle full wave rectified sine. In other words, a wave that
>looks kind of 'spiky' like this:

>(format this diagram with a monospaced font such as Courier)

> | | |
>_/ \__/ \__/ \__

>Just thought I'd throw that into the discussion.

>In fact, let me throw in another "beat the dead horse" comment:
>Phasers work great with Shepard function generators as modulators...

I agree wholeheartedly, maybe down the road apiece Paul will introduce one --
given time for us to acquire 8 VCOs, 8 VCFs, 8 Phasers, etc.

And Ken, this phaser will undoubtedly have a "KILL" setting! For self
destruct, it is often just enough to plug the modules output into its input.

John B.
Oh yeah! Pole switching is nice and an envelope follower (even a cheesy one)
might be an interesting idea, I've never tried it before.