ELECTRO HARMONIX DELUXE MEMORY MAN ANALOG DELAY

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This Electro Harmonix Deluxe Memory Man arrived at my door looking like the road-worn beast you see above. This big box analog delay is a favourite among many musicians and this one has seen a gig or few. But when opening it up, I also realised it had seen the rough end of a soldering iron. Some PCBs and pedals (especially Electro Harmonix ones) are very fragile and do not like too much heat. If you do not have good soldering (and as important, de-soldering) technique, too much heat will inevitably be applied. Tracks will be lifted with no solder flowing through the component holes. This poor DMM had burn marks, cold solder joints and globs of solder on the PCB. One of the best tutorials I have seen for soldering and de-soldering is from the guys at Make Magazine. A worthwhile 19 minutes to brush up on your soldering skills. Just excuse Joe’s inability to correctly pronounce the word “solder” :)

On this pedal, true bypass was attempted, although the indicating LED was wired in reverse and some foam was stuck to the board to hold some wires in place. Unfortunately, the rich, warm echoes of this pedal were distorting badly so a re-calibration was required. The re-calibration involves finely tuning five trimpots with the aid of a function generator, oscilloscope and a good set of ears. At least I have two of those.

After fixing as much of the previous damage as possible, an input gain reduction mod was done to reduce the clipping of the first stage of the pedal. Sadly it wasn’t a completely happy ending. The BBD chips were the culprits of the distortion and are hard to replace, and it could only be re-calibrated to 75% working order. But still, hidden amongst the burn marks and solder globules, were the dark, haunting vibrato repeats of the Deluxe Memory Man, keen to hit the road for a while yet.

C.

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2 Responses to “ELECTRO HARMONIX DELUXE MEMORY MAN ANALOG DELAY”

  1. underwood says:

    Hello,

    have you an manual or infopage how to calibrate the 5 trimpots of the DMM?

    Thanks
    underwood

  2. cubisteffects says:

    Calibrating the DMM is an involved process that I wouldn’t suggest unless you are confident in using an oscilloscope. If so, send me an email and I can pass it on.
    Cheers,
    C.

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