ADA Depot Too - A Forum To Support Users of ADA Amplification Gear

Please login or register.

Login with username, password and session length
Advanced search  

News:

Board added for "Routing & Patching" in Lets Get Technical

Pages: 1 [2]   Go Down

Author Topic: Pooched my MP-1! Help! (yes, I'm embarrassed!)  (Read 3790 times)

0 Members and 1 Guest are viewing this topic.

Kim

  • Administrator
  • Hero Member
  • ******
  • Offline Offline
  • Posts: 663
  • Circle in the Night, a Fire within.
    • View Profile
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #15 on: Time Format »

 :o 

Just when you think you've seen it all... :facepalm:
Logged
RIG OF FIRE:  ADA MP-2, Rocktron Xpression, Peavey Classic 60/60, Gator GPB-BAK-1 pedalboard, Rolls MidiBuddy, Morley Tremonti wah.
Mellotron/organ section:  EHX Mel9, EHX C9, Saturnworks A/B switch, Vox V860 volume, Crate Powerblock.
Pair of 4x12 cabs:  each custom wired for both 2x12 guitar and 2x12 Mel9. UPDATED DIAGRAMS
HOME/STUDIO/COMBOS/STUFF:  Peavey JSX halfstack, Crate G60XL, Saturnworks Saturn Fuzz,  EHX Soul Food, ProCo Rat, Saturnworks buffered splitter, Peavey PV6, Korg DTR-1000.
GUITARS:  Jackson KE3-DiMarzio Breed/PAF Pro, Jackson KE3-DiMarzio Breed/PAF Pro, Silvertone P-bass, '70s Gretsch Dorado acoustic.
WISHLIST

shredbaron

  • Newbie
  • *
  • Offline Offline
  • Posts: 26
    • View Profile
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #16 on: Time Format »

REALLY? that why it doesn't work. A transistor is not suited for this and that's why your voltages on G were out of spec.
Now I've seen this before but on the input section, the FET goes down so let's put a transistor in it, that would work fine , euh NOT. You can't believe what some tech's do.

Yeah, I realized this MP-1 had been modded before, there are sockets on some of the ICs that I didn't put in that don't exist on my other MP-1.

No biggie. Got everything finished up today except the replacement of the tubeboard 2SK364 FETs. Military spec 1% metal film resistors in the audio path, replaced all the caps (electrolytic, NP and ceramic) with upgraded versions, did the bass warp pot, mid-scoop pot, replaced the TL072s I had in U11 and U15 with NE5332 op-amps...this things is better than new inside.

Only thing remaining is to get those FETs sorted out and then figure out why the chorus isn't working. I read the other chorus thread, tried a few things, still nothing - so I'm thinking either the trim pot is bad, or the IC has failed. We shall see.

Logged

shredbaron

  • Newbie
  • *
  • Offline Offline
  • Posts: 26
    • View Profile
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #17 on: Time Format »

REALLY? that why it doesn't work. A transistor is not suited for this and that's why your voltages on G were out of spec.
Now I've seen this before but on the input section, the FET goes down so let's put a transistor in it, that would work fine , euh NOT. You can't believe what some tech's do.

2SK364s arrived today - just installed them - BOOM! everything works great!

just going to replace the volume pot and see if I can sort out the chorus, then it's going back into my rig for some full-volume testing - from what I could tell playing it through my small practice amp, it's a LOT quieter and the EQ is more responsive after replacing all the internals, but I'll know better when I get it going through my tube power amp and 4x12

thanks for the amazing help, it's been very much appreciated
Logged

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 3624
    • View Profile
    • marshalljmpmodshop.net
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #18 on: Time Format »

Aaah great !!!! let me know if I can be of any assistance with the chorus
Logged

shredbaron

  • Newbie
  • *
  • Offline Offline
  • Posts: 26
    • View Profile
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #19 on: Time Format »

Aaah great !!!! let me know if I can be of any assistance with the chorus

Thanks, I'm thinking it's a bad trimpot. I was able to get some chorusing but it cut in and out with the pot. I'm going to replace it with a new 20K pot (if I read the schematic correctly), hopefully can figure out which one will fit via Mouser.

cheers

george
Logged

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 3624
    • View Profile
    • marshalljmpmodshop.net
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #20 on: Time Format »

531-PTC10V-20K  This one should be the correct one (I hope  ;) )
Logged

shredbaron

  • Newbie
  • *
  • Offline Offline
  • Posts: 26
    • View Profile
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #21 on: Time Format »

531-PTC10V-20K  This one should be the correct one (I hope  ;) )

Thanks! I was vacillating between a couple of different options last night and thought I'd sleep on it (this was one of them) - really appreciate the heads up!

Logged

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 3624
    • View Profile
    • marshalljmpmodshop.net
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #22 on: Time Format »

No problem!
Logged

Iperfungus

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 629
  • Methodical killers do good jobs!
    • View Profile
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #23 on: Time Format »

Another MP-1 came back to life!  :thumb-up:
Logged
On the run again!

Rack stuff from Hell:

ADA MP-1 (modified by MJMP)->TC Electronic G Major->Marshall Valvestate 8008 power amp

Marshall JMP1->Alesis Quadraverb GT->Advance Tube Technologies TA '70 tube power amp

Zoom 9150->Marshall Valvestate 8004 power amp
Zoom 8050 MIDI Controller
Zoom FP01 Expression pedal

Behringer FCB1010 MIDI controller

Blackstar HTV 212 stereo cabinet with 70/80 Celestion speakers

Amps:

Rivera Pubster 25
Blackstar Fly 3 amp + external speaker

Stomps, stomps, stomps...and stomps (Bogner rules!):

TC Helix phaser, Xotic RC Booster, TC Sentry noise gate, Bogner Ecstasy Blue, Bogner Ecstasy Red, Mad Professor Royal Blue Overdrive, Sonic Research Turbo Tuner, TC Flashback delay

Guitars:

2018 Arrogantia Pandora Vendetta 24 HH Trem-1987 PRS Custom-1988 Fender Strat Plus-2016 Custom assembled Fender Strat-2013 Gibson SG Standard-1995 Gibson Les Paul Studio-1991 MIJ Ibanez RG570FM TB-2016 MIJ Ibanez RG655M SPM-2002 Bruno Traverso Custom "Tommy" Silky-2017 Kramer Baretta Special-2010 Simon & Patrick Woodland CW acoustic

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4657
    • View Profile
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #24 on: Time Format »

Another MP-1 came back to life!  :thumb-up:
A new take on mouth-to-mouth resuscitation  :lol:
Logged
Studio Rig: MP2/MB1 > Eurorack UB2442FX-Pro > TC M-One XL > Behringer Truths (with Truth Sub) / QUAD ESL 63s
Live Rig: MP2/MB1 > Alesis Quadverb > Alesis Midiverb 4 > Yamaha AM802 > B200s/Carvin TS100/DCM200L > ADA Split Stacks/Mesa P112s

Iperfungus

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 629
  • Methodical killers do good jobs!
    • View Profile
Re: Pooched my MP-1! Help! (yes, I'm embarrassed!)
« Reply #25 on: Time Format »

Another MP-1 came back to life!  :thumb-up:
A new take on mouth-to-mouth resuscitation  :lol:

 :lol: :lol: :lol:
Well, I would prefer a redhead...
Logged
On the run again!

Rack stuff from Hell:

ADA MP-1 (modified by MJMP)->TC Electronic G Major->Marshall Valvestate 8008 power amp

Marshall JMP1->Alesis Quadraverb GT->Advance Tube Technologies TA '70 tube power amp

Zoom 9150->Marshall Valvestate 8004 power amp
Zoom 8050 MIDI Controller
Zoom FP01 Expression pedal

Behringer FCB1010 MIDI controller

Blackstar HTV 212 stereo cabinet with 70/80 Celestion speakers

Amps:

Rivera Pubster 25
Blackstar Fly 3 amp + external speaker

Stomps, stomps, stomps...and stomps (Bogner rules!):

TC Helix phaser, Xotic RC Booster, TC Sentry noise gate, Bogner Ecstasy Blue, Bogner Ecstasy Red, Mad Professor Royal Blue Overdrive, Sonic Research Turbo Tuner, TC Flashback delay

Guitars:

2018 Arrogantia Pandora Vendetta 24 HH Trem-1987 PRS Custom-1988 Fender Strat Plus-2016 Custom assembled Fender Strat-2013 Gibson SG Standard-1995 Gibson Les Paul Studio-1991 MIJ Ibanez RG570FM TB-2016 MIJ Ibanez RG655M SPM-2002 Bruno Traverso Custom "Tommy" Silky-2017 Kramer Baretta Special-2010 Simon & Patrick Woodland CW acoustic
Pages: 1 [2]   Go Up