dlx electric mistress - through-zero mod

[jmasciswannabe]

From what I gather this can be done by adding a small delay in the DEM's dry signal (hammer). I found this:

http://diystompboxes.com/sboxforum/viewtopic.php?t=25168&highlight=throughzero

but looks like the latest revised schematic is missing. Does anyone have this? Also, could anyone suggest a spot in the dry signal to insert the small delay circuit? I plan on making the delay circuit on a separate perf and wire it in.

http://www.generalguitargadgets.com/diagrams/dmistsc.gif

[Mark Hammer]

Doesn't the DEM have dry-only and wet-only output jacks?  If so, then adding the indicated group delay after the dry output, and THEN feeding the dry-only and wet only to a mixer stage ought to do what you want.  The question is whether the wet signal goes down to a short enough min delay that a half millisecond delay/stagger on the dry signal will produce through zero flanging.  I'm not saying it's impossible, just that it would require the DEM to normally dip below 0.5msec and I don't know it it does that.  If you have to go to the extent of building TWO of the shown group-delay allpass monsters, hell may as well try and find another SAD1024 and build a second DEM or find some other way.

A buddy of mine has 2 or 3 of them (originals, not clones or reissues), and I'm curious to see if we can rig them to use the fixed/comb setting on one for  "dry stagger" and then combine it with the wet only output of another in sweep mode to get TZF.