ampage Tube Amps / Music Electronics	For current discussions, please visit Music Electronics Forum.

ampage archive

Vintage threads from the first ten years

previous: Mark Hammer AT LAST!!! Electric mistress mods -- 4/26/2000 3:30 AM

Why mount new pots? Reissue, right?

4/27/2000 2:50 AM
Synthbum	Why mount new pots? Reissue, right? Tweaking the EH Deluxe Electric Mistress reissue is easily accomplished without mounting and wiring new pots. Plug it in, turn it on, turn it over, and take off the bottom cover. I presume most if not all of the reissues are like mine and use PCB EC1000, REV B - visibly identified along the left side. If so, there are four trim pots arranged in sort of a lopsided 'T' pattern with holes through the PCB to adjust them from the bottom. Couldn't be easier. * The top left trimmer (all adjustable with a small phillips or flat head) is near the COLOR knob and governs regeneration. Counter-clockwise turns will induce strong squealing so it's best to set it just short of oscillation. Of course, clockwise turns soften the regeneration effect. * The middle trimmer along the top of the 'T' sets the mix. It mixes dry to fully wet with counter-clockwise turns increasing the effect mix. Good for getting some wobble-tone. * The trimmer at the right end of the 'T' pattern is the bias (I assume) and affects the overall flange action. Fully clockwise yields a not-half-bad overdrive but it's on full-time so... Counter-clockwise erases the flanging entirely. Set around mid-point or leave as is. * The trimmer at the base of the 'T' sets the delay time with counter-clockwise being the shortest. With this set at minimum, really wide sweeps can be had but at the very top of the cycle (shortest delays) with regen way up, it will momentarily click out as it hits zero and can't go higher (in sweep pitch). It's best to increase the delay trimmer about a quarter turn or just enough to eliminate that 'click-out'. That is if very short delay times are needed. I usually leave mine maxed clockwise. No clock filtering trimmer around. I may yet measure the trimmer points precisely and drill some 1/4" holes in the bottom so that I don't need to remove it whenever adjustments are necessary. Haven't gotten around to it yet. May also swap out that 4558 with a TL072 since that supposedly cleans it up. I have some laying around. I just haven't had any big objections to it as it is so far. Nice sounding flanger! Bright and rich. Very flexible. Still miss that old ADA though. =(

4/27/2000 2:50 AM

Synthbum

Why mount new pots? Reissue, right?

Tweaking the EH Deluxe Electric Mistress reissue is easily accomplished without mounting and wiring new pots. Plug it in, turn it on, turn it over, and take off the bottom cover. I presume most if not all of the reissues are like mine and use PCB EC1000, REV B - visibly identified along the left side. If so, there are four trim pots arranged in sort of a lopsided 'T' pattern with holes through the PCB to adjust them from the bottom. Couldn't be easier.

* The top left trimmer (all adjustable with a small phillips or flat head) is near the COLOR knob and governs regeneration. Counter-clockwise turns will induce strong squealing so it's best to set it just short of oscillation. Of course, clockwise turns soften the regeneration effect.

* The middle trimmer along the top of the 'T' sets the mix. It mixes dry to fully wet with counter-clockwise turns increasing the effect mix. Good for getting some wobble-tone.

* The trimmer at the right end of the 'T' pattern is the bias (I assume) and affects the overall flange action. Fully clockwise yields a not-half-bad overdrive but it's on full-time so... Counter-clockwise erases the flanging entirely. Set around mid-point or leave as is.

* The trimmer at the base of the 'T' sets the delay time with counter-clockwise being the shortest. With this set at minimum, really wide sweeps can be had but at the very top of the cycle (shortest delays) with regen way up, it will momentarily click out as it hits zero and can't go higher (in sweep pitch). It's best to increase the delay trimmer about a quarter turn or just enough to eliminate that 'click-out'. That is if very short delay times are needed. I usually leave mine maxed clockwise.

No clock filtering trimmer around. I may yet measure the trimmer points precisely and drill some 1/4" holes in the bottom so that I don't need to remove it whenever adjustments are necessary. Haven't gotten around to it yet. May also swap out that 4558 with a TL072 since that supposedly cleans it up. I have some laying around. I just haven't had any big objections to it as it is so far.

Nice sounding flanger! Bright and rich. Very flexible. Still miss that old ADA though. =(

Replies:

Cole Re: swapping the 4558 for a TL072: ... -- 4/27/2000 3:40 AM
Mark Hammer It appears that everything which wa... -- 4/27/2000 1:35 PM