Friday, 21 August 2009

More Hazarai! EHX SMMH Modification


Rechner7's modded EHX Stereo Memory Man with more Hazarai!

Following this thread at sequencer.de where ACA describes how he modded his Akai Headrush, I asked Rechner7 how he'd modified his SMMH and he kindly sent me these pictures, sound clips and details.





MOD DETAILS:

smmh-mod by rechner7.

inputs:
trigger/gate A
trigger/gate B
trigger C

switches:
REC ON-OFF
SELECT A-OFF-B
HP A/B ON-OFF

input C is always active and high-pass filtered to avoid a unintentional activation of the loop-mode. the high-pass is just a passive 1-pole high-pass with a cuttoff frequency at about 1-3Hz. a selective remoted looping can be done with A or B.
using the REC switch is equivalent to an enduring press of the tap button. this function is handy for long and pitchable delays in the loop-mode.

the function SELECT activates the additional trigger input A or B.
switching HP A/B to ON enables a high-pass filter. if the high-pass is active, A or B cannot release the loop function. bypassing the high-pass (HP A/B OFF) will activate the loop-mode if the gate length exceeds the threshold.

http://www.doepfer.de/faq/gen_faq.htm

paragraph: Converting Gate to Switched Trigger (S-Trigger)

http://www.doepfer.de/DIY/a100_diy.htm
paragraph: 2. Basic circuits


You can download a zipped folder with more pictures, the text and audio examples here (6MB).

Thanks to Rechner7 for sharing this! If you want to attempt this simple but Hazarai-enhancing mod, beware: apparently the hardest part is freeing the PCB from the enclosure without breaking it. Neither I nor Rechner7 take any responsibility for your SMMH. Just so that's clear, OK? Happy Modding!

4 comments:

Pete Shambler said...

This looks like a great mod. I've wanted a VC delay forever, but at a price of at least half of what Moog is asking.

This could be just the ticket!

Was the mod itself particularly tricky to do?

Navs said...

No idea, but Rechner7 assured me it was simple.

The key thing is feeding the tap button some extra triggers, I think simply by connecting extra wires to it. The additional features are there to avoid re-triggering etc.

A project for the dark days of winter ...

Riccsadism said...

Hi, i'd like to know if it's possible to just mod the hazarai for a synch trigger input, just so i can synch the delay time to a certain clock without having to do the whole mod part for starting and stopping the looping function as i don't really use that pedal for recording loops. Thanks!

Navs said...

Hi Riccsadism, one of my very late replies! Yes, that's what the trigger mod does. You just need to HP filter your gates or make sure that they are short triggers, else the SMMH will turn on loop mode. Rechner7 made this a switchable option.