[sdiy] Ultra Flanger: no input filter?

[aankrom]

I have been wanting to make John Hollis' Ultra Flanger, but I'm curious 
as to why there's no input anti-aliasing filter. My guess is that the 
the lowest clock swing is 50 kHz - well enough above Nyquist. I'm 
tempted to use the late, great Juergen Haible's 36dB/oct LPF using a 
single LM301 (from his 1st Stormtide Flanger) at the input - although I 
don't know how well it will work @9V.

Hollis' design really is clever and the flanger should sound really 
awesome. I suppose if one assumes the effect is in a chain in a guitar 
rig with some kind of distortion pedal before it, this will provide some 
high frequency roll-off (as most distortion pedals do).

I'd also considered using as MN3006 and increasing the clock to 
100kHz-2MHz. But I don't think a 128-stage BBD would sound good in a 
flanger. Vibrato maybe, "stereo expansion" definitely (I use them for 
that all the time - you put an L-R signal through the MN3006 and mix it 
back to the stereo signal...) But I digress...

Is the short answer that the point is to make it a low parts count 
project? Anyone have a go at making one?

I've had the same dilemma with EH's Electric Mistress, but at the other 
end. And this flanger is uber-popular...

AA