True Bypassing a Reissue Deluxe Memory Man????

Started by AC30Dirty, February 19, 2007, 01:18:02 PM

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AC30Dirty

Hey guys, I was wondering if anbody here has true bypassed thier Deluxe Memory Man. My pedal comes with a 3PDT switch already but I read that its not wired for true bypass at all. They said that it uses a realy switch or something like that. The switch on my pedal only had 2 wire connected to it as well. I looked at the mods Aron described but the true bypassing description is totally different from what I have. Could anbody walk me through this?? Thanks

sfr

I've not noticed any tonal problems with the bypass on newer EHX pedals. 

If it does use relays, then it's probably still "true bypass", just the bypass is occuring somewhere other than the switch.  You're still passing the signal through uninterrupted metal contacts around the pedal circuitry.  Although being a delay (I believe that's what the DMM is?), it may just kill the echoed signal. 

Rather than hacking at a rather expensive pedal, I'd build a true bypass externally - you don't even need a stomp switch or an LED or a box, just use a toggle and wire it up breadboard or whatever - and see if it makes an audible difference to you.  If it doesn't, than go back to playing and don't worry.  If it does make a difference, I'd still go the external bypass box route.  (Although part of that for me would be because EHX pedals are rather large, and the knobs are fun to twiddle, and bypass boxes allow you to get the pedal up to waist height with the on/off still on the floor)

Just my two cents.

Any offboard wiring diagram (like those at Tonepad or General Guitar Gadgets) will show you how to wire the true bypass, you'll just need to identify the inputs and outputs (which will be coming off the jacks) and how to convince the pedal to be in an "always on" state - if bypass is controlled by a latching type switch, this is easily accomplished by finding out what needs to be connected when the pedal is "on" and shorting this connection to always be made.  (Or, possibly what needs to be "off" and making sure this connection is not made.)  If it uses a momentary switch, then things get a little more interesting. Something someone with a little more familiarity to the pedal in question can probably help you with, or you could provide us with more information.

Sorry for long post that's probably not much help.
sent from my orbital space station.

joegagan

I know nothing about the wiring of this pedal. but it is possible that the switching was designed to have your delays trail off naturally after the switch is hit. this is a good feature of a lot of delays, makes them more musical.

does yours currently do this?

my life is a tribute to the the great men and women who held this country together when the world was in trouble. my debt cannot be repaid, but i will do my best.

AC30Dirty

Well, thanks guys for the info. I first got intersted in bypassing the DMM by what I read on analogman's website. I know they do it but, i play so often that sending it in would be a porblem. I've true bypassed things before but, with this pedal i really want to be careful because I LOVE THIS PEDAL!!!! Supposedly it sounds better when its true bypassed off and on and I guees i'm just really curious to try it. I'm gonna try and post some pics of the pedal to see if maybe you guys can still help me out.

AC30Dirty

OK, here are some pics of the board with the wires. The jack above the 3PDT switch is the output jack. I relocated it to the side where it can be easily accessed for pedal board reasons. If you look closely you can see the labeling on the wires.




tiges_ tendres

I think a lot of people complained about noise in this pedal, so it makes sense that it is bypassed this way with some kind of electronic switching system.  Less wire (usually) = less noise.

Try a little tenderness.

aron

I really doubt they are using relays.

Check out this article I wrote and see if it helps:

http://www.diystompboxes.com/pedals/mmmod.html

Processaurus

I'd usually be against true bypassing pedals that don't do something uncouth to the signal, but the DMM is a good one because it doesn't have an LED indicator, and also it has a percieved volume drop because of the nature of the panning blend control (same complaint goes for the Holy & Holier Grails), so if it were TB'd you'd be able to use the volume knob as a volume control for the effect alone.  Seems like when I see people using these in a live band, when they hit it their instrument seems to get lost, even though its a beautiful sounding effect on its own.  For the bypass LED I used a bi-color one, so it would still show the power was on.  I was a darned fool for selling that one, even though I got it for $10 because someone had botched a repair and switched the input signal and ground on the jack :icon_twisted:

Aron's mod is good too, while you have it apart.

AC30Dirty

I did put a TL072 chip in U1 and it really did improve the sound. I think I may have figured out how to true bypass the pedal by looking at some references on how to true bypass an effect on GGG. All I need to do is figure out where the effect input and output are located. Not on the jacks but on the circuit. Any help????

Processaurus

I see input and output labled on the PCB in your picture.


analogmike

THey are using relays, you should have read my site a little more:

"In late 2004, along with the carboard boxes, there was a redesign on the switching. They are using relays now for true bypass. So if you lose power, the effect will switch to OFF and you will get your true bypassed dry sound. This also makes it easy to mod them for remote or MIDI switching. "

faq "to check if it the new version with the relay, turn it on and play, so you are hearing the delays (effect on). Then unplug the power from the back of the DMM. If it turns off and you hear your normal guitar sound, then it has a relay. If you hear nothing then you don't have the relay. You can also tell as the stomp switch only has two wires on it if you have the relay. "

have fun!
DIY has unpleasant realities, such as that an operating soldering iron has two ends differing markedly in the degree of comfort with which they can be grasped. - J. Smith

mike  ~^v^~ aNaLoG.MaN ~^v^~   vintage guitar effects

http://www.analogman.com

joegagan

thanks for the info aron and mike

so mike, does this mean that your note trails are still on after switching?
what was it like before the relays?
my life is a tribute to the the great men and women who held this country together when the world was in trouble. my debt cannot be repaid, but i will do my best.

puretube

QuoteThey are using relays now for true bypass. So if you lose power, the effect will switch to OFF and you will get your true bypassed dry sound. This also makes it easy to mod them for remote or MIDI switching

so the original Pure-Tube-Technology "powerfailsafe" True Bypass
already mentioned here,
has found its way to update/mod successful vintage E-H designs...  :icon_biggrin:
:icon_wink:

:icon_cool: 

analogmike

Of course EH would learn from you, Ton!!

But I saw that feature on the Foxrox Captain coconut first  ;D
DIY has unpleasant realities, such as that an operating soldering iron has two ends differing markedly in the degree of comfort with which they can be grasped. - J. Smith

mike  ~^v^~ aNaLoG.MaN ~^v^~   vintage guitar effects

http://www.analogman.com

puretube

longer than 11 years ago? :



:icon_smile:



[copy: courtesy of "Erlanger Nachrichten"]

Processaurus

Aah, if its the recent relay DMM he has, what I suggested is redundant, as is true bypassing it.  Do the new ones use an LED indicator as well?  If not it would be easy to use an empty pole on the 3pdt to light it.

boyersdad

That REALLY suprises me that they'd use a 3PDT when all they need is an SPST! Isn't the reason for the other than TB bypasses to save $$$ on switches?

On the other hand, since it's relay switched, I'd say leave it and replace the switch with an Alpha or Carling SPST and use the 3PDT for something else ;)
I like amps etc.

Seljer

Quote from: boyersdad on February 22, 2007, 07:01:16 PM
That REALLY suprises me that they'd use a 3PDT when all they need is an SPST! Isn't the reason for the other than TB bypasses to save $$$ on switches?

On the other hand, since it's relay switched, I'd say leave it and replace the switch with an Alpha or Carling SPST and use the 3PDT for something else ;)

they just use whatever they stock, if you've allready ordered 50000 3DPT switches, why bother with getting something else?

joegagan



Quote from: Seljer on February 22, 2007, 07:02:56 PM

they just use whatever they stock, if you've allready ordered 50000 3DPT switches, why bother with getting something else?


exactly.  same reason GM had millions of cars with 350 small blocks when other engines might have done the job
don't get me wrong, I LOVE small blocks
my life is a tribute to the the great men and women who held this country together when the world was in trouble. my debt cannot be repaid, but i will do my best.

aron

Wow. Why would they use relays? Oh well. I guess I can understand that but if power turns off - most of our pedal boards will be dead anyway. Including the amps.