Home › Forums › Help/Technical Questions › DMM reissue big box , far from 550 ms !

Viewing 15 posts - 1 through 15 (of 21 total)
1 2
  • Author
    Posts
  • December 14, 2009 at 3:17 am #79516
    electricsky
    Member

    i bought a DMM in 2003 or so ( ac adapter powered , 2x 3005, modern round knobs, wooden box ) along with some other ones ( Q-Tron + / micro synth both big boxes, US big muff, sovtek big muff possibly some other i don’t remember).
    i had noticed at that time the delay was quiet far from the 550 ms advertised , despite i had bought it specificaly to get those long delays !
    i was not really happy , so i didn’t use it for a while.
    not really cool for a pedal i bought quiet expensive; they are expensive in France ; at least they were !
    i had read about the fact they have different delay time between units but when i recorded it today and compared in logic audio the wave forms using a tc delay setup first at 500 ms and then at 400 ms, i see teh first repeat of the DMM is even before 400 ms (maybe 375 ms) whereas the delay time pot is maxed .
    it seems many people have had that sort of problems , so much that there are some people out there that made a buisness to have them work correctly or upgrade them ( LOL) .
    i can cope with the fact they have their own design and inherant problems but the fact they are sold for 550 ms when some seem to barely reach 400ms , is a real problem !
    i bought it to have long delays as i already have short delays stomp boxes.
    i wouldn’t have bought it if i had knew about it or i would have asked the shop to try all the units they had to find one working correctly .

    so my question is quiet simple : how do i make it work correctly without spending more money !
    i live in France, so i wouldn’t like to bother sending the pedal to the USA as it would cost me too much money whereas it should be working .
    at worst, i can take it to a local tech but will they know how to do it correctly (i don’t know if they need some infos apart from the schematic that i don’t have anyway) ?
    or i can do it myself if it’s some simple trimmer settings or if it’s just a few simple parts to replace on the board (i don’t know how to use a scope).
    if i was the only one it might be an isolated problem but it seems it’s most of them that don’t get to the 550ms (don’t know for the very last ones ).
    thanks for your help.

    December 14, 2009 at 9:57 pm #105346
    SanquiFlerb
    Member

    I think it’s a trimpot issue. Someone that owns one will pop up and tell you what you could do. This is everything that, at least, I can do

    December 14, 2009 at 11:08 pm #105349
    electricsky
    Member

    thanks for your answer.
    i hope it’s just a simple trimmer i can setup without a scope or just one or two componants to replace at wosrt , cause it’s really frustrating.
    the delay ” color” is interesting but it’s much too short for a 550ms delay !

    December 15, 2009 at 2:58 am #105359
    SanquiFlerb
    Member

    My guess is, there are several pots inside -I don’t own one- so it would be good if you wait for a better answer, here or somewhere else.

    December 15, 2009 at 3:14 am #105360
    electricsky
    Member

    i think there are 3 or 4 trimmers at the back of the pcb

    January 6, 2010 at 2:38 pm #106131
    electricsky
    Member

    happy new year and best wishes for 2010 !

    nobody to shed some light on that question ?

    January 8, 2010 at 2:43 am #106191
    devnulljp
    Participant

    DMM has 4x MN3008 or 2x MN3005 chips for 8000 stages to get you up to 400 ms delay time, so I think what you’re hearing is normal. Futsing with the trimmers might squeeze out another bit of delay time but it will degrade your signal for sure and it can be hard to recalibrate properly without a scope. I have an old Tokai BBD delay here that someone messed with and it’s taken me ages of fiddling to get a semi-acceptable sound back out of it. If you want longer delay times, sell the DMM and buy something else like an analogue voiced digital delay.

    January 8, 2010 at 3:10 am #106192
    electricsky
    Member

    thanks for the answer.
    mine has the two chips .
    400ms delay max ?
    so why is it sold for 550 ms ?

    January 8, 2010 at 3:20 am #106194
    devnulljp
    Participant

    Don’t you just love marketing people? The ad copy runs “Warm and organic, up to 550ms of vibrant analog echo rivals tape delay” I’m sure legally you can get up to 550 ms delay (but it’ll sound horrible; some restrictions may apply; see press for details; always consult your physician before embarking on any exercise program). Anyway, that’s my understanding of those chips and I may be totally off the mark. Ron or Howard would be the people to talk to, but it probably wouldn’t be a financially feasible idea to ship it to the US to one of those guys or analogman to mod. There must be someone in France that would do it for you though. If you are goign to play with the trimmers, mark them well before you start so you can reset it to the way it was before when it all goes horribly wrong… :D

    January 8, 2010 at 5:06 pm #106211
    electricsky
    Member

    i don’t really want to play with the trimmers, without knowing what i’m doing .
    if it’s not posible to get a DMM big box sounding alright with 550 ms, then their marketing is just bullshit, if it is possible, i would like to know what i have to do .

    so, do these chips can go up to 550 ms with a good tone or not ?

    i don’t want my pedal to be modded, i just want to setup or calibrate it correctly to have what i paid for , a 550 ms delay with the normal DMM tone.
    there might be a shop in Paris i could take it to but i don’t know if they are used to calibrate those pedals.
    i can’t believe i got so little time delay right out of the box !!

    January 8, 2010 at 6:24 pm #106215
    julian
    Moderator

    Yeah, it’s a trimpot problem. I believe Analogman, Ron Neely, and Howard Davis all do trimpot adjustments to get it to 550ms. But they’re all in the US. There is probably someone in Europe who can do it. Maybe Puretube?

    January 8, 2010 at 6:37 pm #106220
    electricsky
    Member

    if it’s just a trimpot setup, then maybe i can find someone here in Paris but i would like to be sure it’s just a trimpot problem and that i won’t get a bad sound once i get more delay time.
    also, i don’ know if they know the calibration procedure here.

    January 8, 2010 at 7:32 pm #106221
    Howard Davis
    Member

    It is NOT a trimpot problem. I designed this pedal, and I know. It is due to component tolerances and other production issues. Do not tamper with the trimpots. I do a mod that extends the delay even beyond 550 msec., but sorry, I cannot do it for free.

    Guitar pedal design engineering, repairs, and custom mods:
    http://howard.davis2.home.att.net/

    January 9, 2010 at 12:50 am #106230
    electricsky
    Member

    thanks for your answer.
    as you designed this pedal, can you tell me what components have such a tolerance that most DMM pedals advertized for 550 ms are barely 400 ms ?

    also, i don’t want to extand the delay time past 550 ms, once again, i just want what i paid for, that’s is to say a pedal with 550 ms delay and a good tone.
    i have not studied electronic but i thought what is making the delay time are the chips inside but i didn’t know there could be such a difference between chips; sounds weird (although if you say they do have such tolerance, i will belive you as i suppose you know about that ).

    why most other delay pedals i tried (ibanez, mxr , maxon …) seem to have more or less the delay time they are advertised for, if there is such a tolerance problem with chips ( MN or other ones like SAD1024, reticon5101 ) ?

    so if i follow you the advertizing was lying as most seem to have much shorter delay time than advertized.

    by the way, as you designed it, could you tell me how much current draws the big box DMM reissue (2003 model with external 24v power supply ) as i would like to use CIOKS Schizophrenic power supply to power it ?

    January 9, 2010 at 1:33 am #106231
    electro-melx
    Moderator

    electricsky, please bear in mind that while Mr Davis designed the deluxe memory man he does not work for EHX anymore, and he has never (as far as I’m aware) worked in the advertising department, so your demands for “i just want what i paid for” should not be directed at him but to EHX via their email. (if you so wish) Mr Davis does independent repairs and upgrades on some EHX pedals and will offer them to you as service if you wish to use them, but clearly he is not responsible for warranty repairs, or customer dissatisfaction with any EHX products, those should be taken up with your dealer or EHX directly. I’m just making this clear as it seems you might be thinking otherwise.

    … that said, Howard is a valued member of this forum and I’m sure he will give you honest advise and help in anyway he can.

  • Author
    Posts
Viewing 15 posts - 1 through 15 (of 21 total)
1 2
  • You must be logged in to reply to this topic.