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EH Electric Mistress sounds thin

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7/1/1998 4:06 PM

Anders Westerberg

EH Electric Mistress sounds thin

I'm doing a job on a EH Electric Mistress (schematic at Stellan Lehrberg's site:http://www.fortunecity.com/tinpan/humperdinck/223/ehmist.gif ) that seems to lack of bass response.
I've asked this question before I was able to try another SAD1024, but that didn't make any difference. I've checked all resistors and caps in the signal chain and even changed the op-amp (yes, a desperate try), nothing seems to help. However, I can get a decent sound by adding large cap values in the two feedback lines. The adjustable bias voltage is correct and the clocking section is working perfectly.
Am I missing something obvious or was these versions of the EH EM known to lack of bass response?

Anders

7/2/1998 8:53 AM

Anders,
The way it sounds, you have already tried adjusting the trim pots on the PCB. Do not rule out that the pots are bad.
Countless times I have adjusted and ohmed out trim pots on these old pedals and they test fine and functional. however, fixing the unusual problem it had would stump me because everything looked like it was operating properly but it's final output was not right. Once I replaced the trim pots the pedal functioned properly on the PCB and at the output.
I am not saying that this is the problem, just do not rule out the trim pots.

Good luck,
Christian

7/2/1998 2:45 PM

Anders Westerberg

That's a good point. However, things happen when I tweak them, but you're right, there could be a chance one of them is bad. I'll check it out as soon as possible.
In the meantime, does someone have any more suggestions? This one is really driving me nuts. I mean, if a customer comes up with one of those Silicon Valley multieffects pedalboard full of SMD's, I can tell him it's not my bag and still be proud, but in this case it's just a handful of caps and resistors.

Anders

7/23/1998 10:09 PM

Re: DeLuxe Electric Mistress schem

Hi there
Many many years ago a friend gave me a semi-destroyed 'Deluxe Electric Mistress', with most of the connections to the jacks and switches broken. As I've never seen a schematic for this box, it found its place in my electronic scrap heap. From reading this thread I went to the schematic pointed by Ander Westerberg. Unfortunately it has nothing to do with the unit I have, which has the SAD1024 and 4013, but also a LM311, LM324 among others. The PCB is identified with EH5150B. Does anybody have or knows where can I get the schem of this box? Any help will be appreciated. Thank you very much.
Cesar

7/29/1998 3:35 AM
Anders	Hey, Cesar! Contact me at: awe@hem.passagen.se I might be able to help you! Anders

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