The dsl joey mod thread

Discussion in 'The Workbench' started by TwinACStacks, Apr 5, 2010.

  1. AndyK11

    AndyK11 Active Member

    Joined:
    Jan 14, 2011
    Messages:
    491
    Likes Received:
    105
    Location:
    NJ, USA
    I just read EVERY post in this entire 50 page thread! I'll be dreaming of caps and resistors coming to kill me in the form of a kangaroo!

    I just want a DSL that sounds more brown, more like a modded Plexi or Friedman Brown Eye on the red channel, to get better early Van Halen tones. No modern, scooped high-gain metal for me! I think there are several red channel mods that would make sense for me to do:

    C12 (tube board) reduced to lower low end early on in the signal path
    C12 (front board) reduced to tame brightness with gain at 12:00 or below
    NFB cap addition to tighten things up
    Anything else?

    You know how when playing on the green channel, and you hit the footswitch to go to red, and you notice a thinner, brighter, almost shrill tone compared to the green crunch? Will the above mods help cure that problem?

    Thanks all!
     
  2. Grogshla

    Grogshla Active Member

    Joined:
    Jul 9, 2012
    Messages:
    780
    Likes Received:
    175
    I have the Joey mods done to my jcm2000 dsl 100w head and it is constantly losing volume and causing the 2 inner power tubes to glow white hot. Any ideas on what could be causing this. I have serviced the amp 3 times and it always has the same issue with the same 2 tubes. I have tried marshall tubes, jj tubes and now on tungsols which just did the same thing. My amp also has 2x classic tone transformers and a choke
     
  3. cudbucket

    cudbucket Active Member

    Joined:
    May 21, 2016
    Messages:
    117
    Likes Received:
    31
    So much great info here. I have my DSL on the bench right now and have done the speaker jack mod as well as replacing C46 with a 1kV cap. Tomorrow, C12 comes out. Can anyone help me with spec'ing the 7 "big" caps on the tube board. This is what I'm planning to order from Mouser.

    330uF 315v: http://www.mouser.com/Search/Produc...RDvirtualkey64700000virtualkey647-UVZ2F331MRD
    100uF 350v: http://www.mouser.com/Search/Produc...HDvirtualkey64700000virtualkey647-UCY2V101MHD
    22pF 450v: http://www.mouser.com/Search/Produc...Svirtualkey66720000virtualkey667-EEU-EE2W220S

    Also, I want to get turrets for the Choke install. What size mounting hole do I need when ordering the turrets? Thanks so much!

    Dave
     
  4. RickyLee

    RickyLee Well-Known Member VIP Member

    Joined:
    May 22, 2010
    Messages:
    8,093
    Likes Received:
    2,059
    Location:
    Riverside CA U.S.A.
    I guess the disparity between many DSL's that left the factory not created equal continues. And now I see there is no magic in the year of '98. My first DSL100 was from '04. I did the mods you mentioned above and then some. When it was stock, it seemed to be very much like you describe. Mine had this fizz in the upper mids that was hard on the ears and just could not be dialed out unless I killed the top end with very low treble settings, mainly on the Red channel I should add. But the entire amp did have an unpleasant plastic sterile tone about it until it was cranked to such a high level that would drown out an entire band and piss off bar managers for sure.

    Then I got a second stock DSL100 from '98 that was at the opposite end of the spectrum. The Red channel was slightly more midrangey but in a very good way. Sweet crunch and very good tone at lower volume settings. I still have not touched this '98 for mods except for installing a choke. There seems to be many more very good ones and bad ones out there with inferior tone and heat/bias issues than ones that are just in the middle of the road for tone. This amp was obviously produced more than any other Marshall that I know of, so that has to play into the recipe with the ingredients just having a slight variation in the final tone outcome.

    I would think your mods should work out for you. Did you try them yet?
     
  5. RickyLee

    RickyLee Well-Known Member VIP Member

    Joined:
    May 22, 2010
    Messages:
    8,093
    Likes Received:
    2,059
    Location:
    Riverside CA U.S.A.
    Has the problem with the tubes getting too hot flared up when the techs were servicing the amp? Was there a problem they said they found and fixed?
     
  6. RickyLee

    RickyLee Well-Known Member VIP Member

    Joined:
    May 22, 2010
    Messages:
    8,093
    Likes Received:
    2,059
    Location:
    Riverside CA U.S.A.
    Did you get your caps ordered yet?

    I think this person sells the recap kits for the DSL100/50 and TSL100/122.

    http://www.lydian.ca/Parts/Pages/Marshall_DSL_Transformers.html
     
    cudbucket likes this.
  7. cudbucket

    cudbucket Active Member

    Joined:
    May 21, 2016
    Messages:
    117
    Likes Received:
    31
    Hey Ricky,

    Yes, I got them ordered and am in the process of installing. Thanks for the info though!

    Dave
     
  8. mikerevis

    mikerevis New Member

    Joined:
    Jul 23, 2016
    Messages:
    3
    Likes Received:
    0
    Question... Removing C46 as a precaution... Ok. Just cut it out or jumper? Thank you!
     
  9. RickyLee

    RickyLee Well-Known Member VIP Member

    Joined:
    May 22, 2010
    Messages:
    8,093
    Likes Received:
    2,059
    Location:
    Riverside CA U.S.A.
    Are you referring to C46 that is on the main board on the V8 socket?

    If so, DO NOT JUMPER THAT CAP! That cap is across pins 3 and 4 of that EL34 socket. That cap can just be snipped off. Or if you want to keep it, upgrade it with a 1000 volt rated and use the same value.
     
    mikerevis likes this.
  10. mikerevis

    mikerevis New Member

    Joined:
    Jul 23, 2016
    Messages:
    3
    Likes Received:
    0
    I was referring to C46 the cap that can potentially take out the ot. I believe you answered my question... Snippy snip snip! Thank you!
     
    Last edited: Jul 24, 2016
  11. mikerevis

    mikerevis New Member

    Joined:
    Jul 23, 2016
    Messages:
    3
    Likes Received:
    0
    Ok Guys. She's fired up. Now, the first two tubes (DSL 50 head counting from input to power) the first two preamp tubes light up normally, then volume fades and the "Lights" go out on them. The first two only... Swapped for a known good pair of 12ax7's, and... Same thing. Help!!!
     
  12. RickyLee

    RickyLee Well-Known Member VIP Member

    Joined:
    May 22, 2010
    Messages:
    8,093
    Likes Received:
    2,059
    Location:
    Riverside CA U.S.A.
    You need to check heater voltage going to those two sockets. The heaters are AC for the EL34's and also V3 and V4. Then there is a run from the AC to a bridge rectifier that converts to DC for V1 and V2. Start with that as your first check. My 2005 TSL100 has a huge 6 amp bridge rectifier on its PCB. I do not know if Marshall upgraded those at some point, but that 6A on my PCB is way beyond what is needed.
     
  13. Cascadem

    Cascadem New Member

    Joined:
    Aug 4, 2016
    Messages:
    28
    Likes Received:
    1
    Hello, new to the forum but have been following it for a long time from the outside world lol.
    I have many questions for this thread, for now:
    I have jumpered R12 on the pot board, love it, does jumpering R20 do the same for the red channel as R12 did for the green?

    Seems like the green channel has slightly more output to the poweramp than the red at this point after jumpering R12. I did adjust the C8 4n7 cap in the green channel to .0022 and now both channels are very similar in eq but just trying to give the Red Channel a kick in the ass like I did the Green.
     
    Last edited: Aug 5, 2016
  14. tripptripp

    tripptripp New Member

    Joined:
    Aug 11, 2016
    Messages:
    2
    Likes Received:
    0
    Hello All, first post here. In troubleshooting my jcm 2000 DSL 50 (made in 2000), I came across this awesome thread and have been doing some of the mods. In the process I'd like to do the preventative maintenance including the grid blockers, but I'm not sure which resistors are the grid blockers on my board. I haven't seem anyone mention my version of the main board or I could have missed it in the 50 pages that make up this massive thread. It's a jcm2-60-00 iss5. Any help will be greatly appreciated!
     
  15. RickyLee

    RickyLee Well-Known Member VIP Member

    Joined:
    May 22, 2010
    Messages:
    8,093
    Likes Received:
    2,059
    Location:
    Riverside CA U.S.A.
    Jumpering R20 would give the Red channel a bit more high end and a bit more gain as well.

    But to get the same effect as what you did on the Crunch channel, you would want to jumper R19. But that will increase gain in that channel quite a bit and then make Lead2 possibly usuless. It might make Lead1 too gainy to where you then dial back the Gain control to compensate, which will then add more high end (unless you already removed C12?).
     
  16. RickyLee

    RickyLee Well-Known Member VIP Member

    Joined:
    May 22, 2010
    Messages:
    8,093
    Likes Received:
    2,059
    Location:
    Riverside CA U.S.A.
    I was only able to find the DSL50 2003 main board scheme. It shows the control grid resistors as R66 and R70 and it shows them as the proper 5.6K value. I am sure those resistor numbers should be the same on your main board.

    Have you verified your board has the 220K there?
     
  17. tripptripp

    tripptripp New Member

    Joined:
    Aug 11, 2016
    Messages:
    2
    Likes Received:
    0

    Hey thanks RL, I didn't get a notification of your reply. I did verify they are 220K. I went ahead and swapped R66/R70 for 5k6ers and everything appears to be fine.
     
  18. Cascadem

    Cascadem New Member

    Joined:
    Aug 4, 2016
    Messages:
    28
    Likes Received:
    1
    No havent removed c12 on the front board yet.
     
  19. Cascadem

    Cascadem New Member

    Joined:
    Aug 4, 2016
    Messages:
    28
    Likes Received:
    1
    Ricky Lee, lets talk about how I voiced my channel 1 first to better understand what I seem to like out of the amp. So, I changed C8 on the front board to .001, removed R7 and jumpered it, removed and jumpered R12. Now this is all on the just the front board. Now to the main board, I changed R12 from 68K to 47K, changed R14 from 1.8k to 1.5k as well as R15 from 1.8k to 1.5k carbon comp resistors used for all changes. I changed all of the amps coupling caps and tone stack caps to Mallory 150 polyester type. The tone stack on the front board has been changed to: C19 remove and jumper, R35 changed to 15K, R36 changed to 19K, C22 has been removed and jumpered, this seemed to be the closest to making my tone stack into a 2204 tone stack without changing pots and yeilded the tone shift switch into a mid boost when disengaged rather than a scoop. Nearly stock when engaged.
    I THINK at this point...I want to tame the high end of the amp in the lead 1 and lead 2 channel. The tone of channel 1 is good. I am using speakers that let alot of high end through and bright pickupsin my les paul so I dont want to tame the high end of the entire amp per say so when I run darker speakers and a thicker darker pup (much like a ducan custom/JB/59custom hybrid/ custom custom) I still have the abiltiy to bring the treble and presence knobs up a tad. As far as bass/low end...I have converted channel 1 reverb into a master reverb control and am now using the channel two reverb as a resonance knob that can cut below stock with deep switch out or...boost up to deep switch in. Kinda makes the deep switch useless unless, you want the full effect of the stock deep switch all at once and fast, no dialing in needed if you use the deep switch...if thays what one wants.
    But lets just focus on what I have done to the preamp and keeping the tone stack changes and cathode and grid value changes in consideration.
    I have been considering trying out removing and jumpering R34 and R37 on the front board as the JCM 800 2204 didnt have them in the circuit at all.
    Walk me through your thoughts lol!
     
    Last edited: Aug 25, 2016
  20. Cascadem

    Cascadem New Member

    Joined:
    Aug 4, 2016
    Messages:
    28
    Likes Received:
    1
    And I should mention that the amp front board is JCM2-61-00 and the main tube board seems to be JCM2-60-00 (labeled buy Marshall as such, however, when I go through the board it appears the component values are closer to the DSL50-60-02).
    Amp is a DSL 50 made in 2003. Running original Marshall Preamp tubes (whatever they actually are) and Winged C power amp tubes. I HAVE been considering trying the JJs KT77 outputs and their standard ECC83 preamps. I have always thought of JJ PREAMP tubes to be a tad on the darker side compared to alotof others out there. That might or might not even tame the high end of the amp. I SHOULD SAY, I am not displeased with the amps amount of high end, however am running my pres on 4, treb on 5, bass on 3, and well my res knob is set about to stock dsl with deep sw out. Mid well, its kind of funny cause I tend to run the boost on and then bring the knob back to around 3....as crazy as that sounds.
     
    Last edited: Aug 25, 2016

Share This Page