PWM on complex audio signals

[Magnus Danielson]

From: Don Tillman <don at till.com>
Subject: Re: PWM on complex audio signals
Date: Tue, 2 Jan 2001 10:14:53 -0800 (PST)

>    From: DCMagnuson at aol.com
>    Date: Tue, 2 Jan 2001 10:02:50 EST
> 
>    I came across a circuit for adding PWM distortion to a guitar
>    signal.  The schematic is located at:
>    http://www.cs.ucl.ac.uk/students/M.Rogers/pwm.html 
> 
> Wow, this is a really bad design.  First off, the input impedance is
> about 1/100th of what you need for an electric guitar.

Ouch!

> Clipping from the first stage can shoot back out the input and
> disturb any other devices connected in parallel.

OUCH!

> Schmitt trigger fuzz generally doesn't work on an electric guitar as
> the signal cuts off abruptly when the player least wants it to.

Not good.

> And Baxendall tone controls just don't sound good with guitar.

Huummmm!!!??!?!!?

There are many reasons not to like Baxendall's tone controls, but I
would please ask you to elaborate some on this topic. I'd also love to
hear some comments on what you would use instead and why.

I personally could do with a refreshment on the discussion...

Cheers,
Magnus - not playing guitar...