The dsl joey mod thread

[motocooney]

Hey, I have a dsl 100...I've only done a few things.

-removed c12 front board
-jumpered r12 and r20
-Classic Tone choke

But...lastnight I tried just desoldering one leg on c4 to see if I liked it.
I also jumped c8.

I'm not 100% percent but I swear the amp isnt as loud overall now. Also, the crunch setting seems to have less gain.

Also, I noticed that the Mullard RI 12ax7 I have in v1 seems to be very dim.

Any ideas?

[motocooney]

Originally Posted by Jason77

As for adding the cap to the NFB resistor, it basically adds clean low end to your signal, making the low end clearer and punchier. It works similarly to how the presence control adds more highs. To me, it has a more natural feel than the deep switch. I like .0047uf but if you want more lows, you could use a .0033uf or even a .0022uf.

The NFB resistor is R19 on the rear board. You just need to disconnect the leg that connects to the 4ohm spade connector and solder the cap in between.

This may be a dumb question but.....I use the 16ohm speaker output. Will this mod work for me?......It sounds like exactly what I'm looking for.

thanks

[RickyLee]

Originally Posted by motocooney

This may be a dumb question but.....I use the 16ohm speaker output. Will this mod work for me?......It sounds like exactly what I'm looking for.

thanks

It will work for all impedance settings.

[motocooney]

cool thanks ricky....I tried the r19 resistor mod and it did exactly what I was hoping it would. Just a bit more low end. This mod alone had a huge effect on my tone.

[myfriendzeppelin]

Hi guys,

Long time listener, first time caller:

I have a big problem with my DSL100. I was going to replace C12 on the main board, so I removed the original. I then realized that the replacement I had was the wrong value, so I put the original back in. I thought I did a clean job at first, but then I put everything back together and turned the amp on; all that came out was a hum (no signal). The hum is directly affected by the volume knobs, so it can be turned all the way down. Both channels (all four modes) are the same. I took the amp apart again and noticed that C13 had shorted out. After trying to replace things and double checking everything, the soldering is a little messier, but everything is making contact. Still, just hum. I don't know if the replacement for C13 is good or not, so I'm going to get new caps tomorrow.

Any clues? Everything else looks fine and I tried replacing all of the preamp tubes with a different (known to be working) set.

Thanks!

[motocooney]

Originally Posted by myfriendzeppelin

Hi guys,

Long time listener, first time caller:

I have a big problem with my DSL100. I was going to replace C12 on the main board, so I removed the original. I then realized that the replacement I had was the wrong value, so I put the original back in. I thought I did a clean job at first, but then I put everything back together and turned the amp on; all that came out was a hum (no signal). The hum is directly affected by the volume knobs, so it can be turned all the way down. Both channels (all four modes) are the same. I took the amp apart again and noticed that C13 had shorted out. After trying to replace things and double checking everything, the soldering is a little messier, but everything is making contact. Still, just hum. I don't know if the replacement for C13 is good or not, so I'm going to get new caps tomorrow.

Any clues? Everything else looks fine and I tried replacing all of the preamp tubes with a different (known to be working) set.

Thanks!

When you pulled the mainboard, did you unhook any connectors?
Are you sure everything is plugged back in correctly?

Why were you messing with c12 on the mainboard ( i assume mainboard is tube board)?

[RickyLee]

Originally Posted by myfriendzeppelin

Hi guys,

Long time listener, first time caller:

I have a big problem with my DSL100. I was going to replace C12 on the main board, so I removed the original. I then realized that the replacement I had was the wrong value, so I put the original back in. I thought I did a clean job at first, but then I put everything back together and turned the amp on; all that came out was a hum (no signal). The hum is directly affected by the volume knobs, so it can be turned all the way down. Both channels (all four modes) are the same. I took the amp apart again and noticed that C13 had shorted out. After trying to replace things and double checking everything, the soldering is a little messier, but everything is making contact. Still, just hum. I don't know if the replacement for C13 is good or not, so I'm going to get new caps tomorrow.

Any clues? Everything else looks fine and I tried replacing all of the preamp tubes with a different (known to be working) set.

Thanks!

Just noticed your post. Did you get the problem fixed?

[myfriendzeppelin]

I only removed one connector, but it's back in the right place. Everything I did was on the tube board, yes. I bought replacements for both C12 and C13 and put them in. I even bought a conductive pen to retrace the places where the caps connect to the board. Is it possible that a resistor or another cap has gone bad without showing any physical signs?

[RickyLee]

These DSL/TSL PCB's have very close solder pads. Very easy to short something out when soldering. It is almost a situation where a magnifying glass, very thin gauge solder and a very small diameter with a sharp point solder tip are needed to work on these amps.

I was leaning towards the idea, that you shorted adjacent solder pads together and you still have solder touching two or more pads of different paths/traces together. And/Or you lost/lifted a solder pad in there as well.

Did you try removing ALL solder on the suspect area as well as the neighboring pad and try it again? A good solder sucker will work here as I had this happen on my DSL as well. Or soldering braid as some people go with.

[myfriendzeppelin]

Originally Posted by RickyLee

These DSL/TSL PCB's have very close solder pads. Very easy to short something out when soldering. It is almost a situation where a magnifying glass, very thin gauge solder and a very small diameter with a sharp point solder tip are needed to work on these amps.

I was leaning towards the idea, that you shorted adjacent solder pads together and you still have solder touching two or more pads of different paths/traces together. And/Or you lost/lifted a solder pad in there as well.

Did you try removing ALL solder on the suspect area as well as the neighboring pad and try it again? A good solder sucker will work here as I had this happen on my DSL as well. Or soldering braid as some people go with.

I did indeed lose both soldering pads while removing one of the caps. They came off like there was nothing holding them on! They only came off on the top of the board, though. On the bottom, everything looks like it should work. I WILL get my magnifying glass out, though. Thanks for the tip.

[RickyLee]

Originally Posted by myfriendzeppelin

I did indeed lose both soldering pads while removing one of the caps. They came off like there was nothing holding them on! They only came off on the top of the board, though. On the bottom, everything looks like it should work. I WILL get my magnifying glass out, though. Thanks for the tip.

A continuity checker and the schematic will do the trick in figuring out if you have some shorts or accidental jumpered terminal connections there. Sometimes some of those extremely close pads are on the same trace/electrical path. So checking the schematic first will save you some panic there.

[xjbear]

The plate bypass cap mentioned on the net possibly dulls the clean channel(390p across R1) but certainly helps darken up the DSL, I was thinking why not do a Plate bypass elsewhere in the amp like on V2B? Just bypass R32 with an appropriate cap, I've included a link to a PBC calculator, just not sure of V2B's input impedence.

What do u all think?

Plate bypass calculator
Plate Bypass Capacitor Calculator

schematic
https://docs.google.com/open?id=1Hmm...-udFMlmgl8d5TC

[xjbear]

forget the post above, I played with the tone stack and got what I want out of it.
I've done all the Joeys mods and still wasnt quite satisfied with the tone, not enough mids, so I clipped out R35 (r35 sets the Q of the mid band) and put in a 5.6k resistor on the leg of an 25k Log pot and that sweeps the mids, looks like leaving it at 5.6k(pot all the way down) is right up my alley, super heavy lowend mids which they overpower the harsh highs and make them sit in the mix better now, also tightens up the lows alot.

turns out that you can turn the mid scoop switch into a mid boost very easily, replace R36 (68k)with a 27k resistor, replace R35 with a 5.6K resistor, switch (pushed In) your at stock DSL settings (33k total), switch out you have a mid boost (5.6k), Cake! or just put the pot in there and sweep it whatever

[xjbear]

well after playing with this mod I believe it is the be all end all of tone searching for me, the eq is now so interactive, I can tweez it perfectly to drive my 1960av cab now, before it was so 1985 and I wanted 1972 and 2012 respectively lol

[xjbear]

oh yea I ended up with a B25K pot with a 5.6k metal film in place of R35, I left the scoop switch value alone being that it has more character engaged with the new mid bump that I can get, not sure if it's actually moving the q or if it's just making the mid pot more invisible but wow it's nice

Ps I also have a 68pf cap across vr4 to bleed some highs too as per tsl100 Europa mods page

[jball1985]

Does anyone know which resistors are the grid blockers for the dsl 50?

[mickeydg5]

Originally Posted by jball1985

Does anyone know which resistors are the grid blockers for the dsl 50?

They are usually R66 and R70 which have one side connected to pin #5 of each power tube.

Are those the ones in question?

[guitargoalie]

The mods that I have done are

Tube board:
C12 = 1uF
R13 = 100K
Front board:
Jump R20
R21 = 220k
C12 removed


This was done by a tech, so I can't say I know what each mod specifically does, other than help get it closer to an 800 (as recommended by a forum member)

The green channel has more gain and the mids are better on both channels. On the red channel I can't even play with the gain past 2 for my style of music, its way too hairy distortion. Should I consider different preamp tubes (currently jj's), or is there a certain cap or resistor that affects ultra channel's gain?

[guitargoalie]

ignore that ^ I think I figured it out

[diesect20022000]

Originally Posted by guitargoalie

ignore that ^ I think I figured it out

it's a long shot (i'm in the very low income bracket) but if i ever get the money i definitely want a build from you man. the tones and aesthetic (and board/wire layout) are immaculate. i have a fetish for amp circuits. i collect pix and plan on making posters of them (and collages) to puut on my walls and just from an aesthetic point of view i can say your layouts are some of the most clean and thoughtful i've seen. but yeah the tone's what makes me want to get some gear sold already so i can get a custom build from you one day.

you francois and a few others......amazing work and great people.

[rockgod212]

well my dsl is back on the bench, i seem to get an annoying crackle from my v30's when i hit certain notes. i dont know if its just resonating, pushing the speakers too much, or whats going on.

other questions though for jcm2-60-02(iss5)

r16- grid to ground resistor, can it be removed or adjusted?
r20/ r27- coupler to ground resistor, can it be removed or adjusted?
r18- grid to ground resistor, can it be removed or adjusted?
c18- what does this cap do, is it some sort of filter or shelving freqs?
how do the LDR's work?

[rockgod212]

never mind, i figured it out. changed a few things though. c10 back to 4n7,
r21= 1m to make the pot 500k ala soldano, added a brite cap switch to red channel= 250p, 470p, 1n. now red 1 and red 2 are more balanced, although i prefer red 1 mode with all the mods i did to my amp.

Originally Posted by rockgod212

well my dsl is back on the bench, i seem to get an annoying crackle from my v30's when i hit certain notes. i dont know if its just resonating, pushing the speakers too much, or whats going on.

other questions though for jcm2-60-02(iss5)

r16- grid to ground resistor, can it be removed or adjusted?
r20/ r27- coupler to ground resistor, can it be removed or adjusted?
r18- grid to ground resistor, can it be removed or adjusted?
c18- what does this cap do, is it some sort of filter or shelving freqs?
how do the LDR's work?

[Ghostman]

I put the Joey Mods back in today, and since I'm not chasing a cable issue, it sounds a lot better. However...

..I have some fizzyness on all channels when I strike a note. The harder the strike the more apparent it's there. Sounds like a little bit of raspyness. Almost like a blown speaker but the speakers are good.

Any ideas?

[gh9597]

OK....I just recenty purchased a DSL 100 head and 1960cab from a friend who was needing some money. Something tells me I think he got the better end of the deal. I have been playing a Mesa Boogie Nomad 45 for 10 years now. Ive never owned a Marshall. For some reason this Marshall is not cutting through like I think its supposed too. It seems I have to crank the gain and volume up on the O.D channel to hear it. My mesa just rips through this cab and my volume is very low. Channel one clean I have gain and volume almost maxed out. The crunch on channel one sounds awesome. 2nd channel has no bottom end. Its very thin and its just not coming through. My volume is on 3-4 and gain is on the same. Is this normal or do I have something going on. Just change power tubes and preamp tubes.

[rockgod212]

i have bypassed my fx loop by removing RL3B and it sounds great without the loop, but does anyone know how to energize or de-energize RL3B with just a switch added, as it looks like all the relay circuitry is there, just need a switch to switch it. or am i wrong about this?

[ChrisYoung]

na

[xjbear]

I did all the Joey mods, still wasn't real happy with it. Tried some other cap roll of mods on the gain and volume pots, still not much help. Wasn't until I changed some tone stack values that things got right, although I have lost some versatility(who cares) it pushes air and does the plexi thing on the clean/crunch with all knobs dimed like it should now. The lead and lead2 are perfect as well. 2 100pf silver micas in parallel in c20, c22 change to 4.7n or .0047 polycap, r38 to 560k or 1m and 1.5m paralleled if you don't have a 560k, c12 is out and r20 is jumper end per JoeyMod.

[xjbear]

Along with a previous mid Q mod I did this is the way for doom sludge metal

[xjbear]

Here's the mid q mod, used a micro stack knob for authenticity

[CRunCH]

Originally Posted by TwinACStacks

Popcorn's good. Anybody got some salt?

TWIN

TWIN, I've been lurking this thread for months and must have always breezed over this comment. Nice stiletto ... and since I'm not in NY, I'll have a 48 oz Big Gulp with that popcorn.