The dsl joey mod thread

[Buggs.Crosby]

Originally Posted by jcmjmp

You have to be very careful when you do that because that connector might go somewhere else depending on the board rev and issue number.

thats why i'm trying to get every known scheme on these....if something cannot be confirmed it will be omitted....and it will tell you this

[tweed]

So does anyone have a step by step hookup of the tranny on the right of the board for a 50w? I think I still have them in the correct order but would be nice to know for sure. Mainly the two purple and 3 blue connections, to bad they didn't make them all different colors.

[TwinACStacks]

You mean like this?

Marshall DSL Transformers

TWIN

[tweed]

Kinda like that.

Here's my tranny



Here's the leads coming off the tranny



And here's where they connect to the main board.



Just have to figure out where the three blue leads and the two purple leads hook to and in what order if that makes sense. After that gets done and I hook all the "cons" together, it's bias and test time.

[jcmjmp]

Originally Posted by tweed

Kinda like that.

Just have to figure out where the three blue leads and the two purple leads hook to and in what order if that makes sense. After that gets done and I hook all the "cons" together, it's bias and test time.

The blue leads are the 22-0-22 taps (W11/W12/W13), the red/orange are the HT (See Schematics) and the purple are the heaters (W9/W10).

If you're not sure on how to hook 'em up, bring the amp in to a tech.

[tweed]

Originally Posted by jcmjmp

The blue leads are the 22-0-22 taps (W11/W12/W13), the red/orange are the HT (See Schematics) and the purple are the heaters (W9/W10).

If you're not sure on how to hook 'em up, bring the amp in to a tech.

I know that the heaters go to w9 and w10 and the 22-0-22 blue wires go to w10 w11 and w12. Just not sure if the purple connections, even though they are both heaters need to connect in a certain order, like the first purple off the tranny goes to w9 then the second goes to w10 or if that even matters, maybe since they are both heaters they are interchangeable. That make sense?

Same for the 22-0-22.

[jcmjmp]

Originally Posted by tweed

I know that the heaters go to w9 and w10 and the 22-0-22 blue wires go to w10 w11 and w12. Just not sure if the purple connections, even though they are both heaters need to connect in a certain order, like the first purple off the tranny goes to w9 then the second goes to w10 or if that even matters, maybe since they are both heaters they are interchangeable. That make sense?

Same for the 22-0-22.

The heaters are interchangeable but not the center tap for the 22-0-22 taps.

[tweed]

Originally Posted by jcmjmp

The heaters are interchangeable but not the center tap for the 22-0-22 taps.

Is there an easy way to determine the order of the 22-0-22? Or am I making it to hard? Are outside blue leads on the tranny the 22's and the middle lead is the 0. Connect a 22 to w11, 0 to w12 and 22 to w13...

[jcmjmp]

Originally Posted by tweed

Is there an easy way to determine the order of the 22-0-22? Or am I making it to hard? Are outside blue leads on the tranny the 22's and the middle lead is the 0. Connect a 22 to w11, 0 to w12 and 22 to w13...

one word of advice - Always double check what you read on the 'net and make your own readings with your own multimeter. Its easy enough to check. If you can't do that, bring it to a tech. With schematics and a DMM, this is a very simple job.


... and this should be in a separate thread - it has nothing to do with modding the DSL.

[tweed]

Originally Posted by jcmjmp

one word of advice - Always double check what you read on the 'net and make your own readings with your own multimeter. Its easy enough to check. If you can't do that, bring it to a tech. With schematics and a DMM, this is a very simple job.


... and this should be in a separate thread - it has nothing to do with modding the DSL.

Ahh sorry about that.. Thanks for the help though

[jcmjmp]

Originally Posted by tweed

Ahh sorry about that.. Thanks for the help though

no prob! Good luck with your amp!

[javier pintos]

well i tried r12 last night and do notice the change, i did not necesarily got a pissed off irish man (dont know any drunk irish man) but rather a drunken mexican tequila dude, however i just tried it like 5 min with some gator clips, i´m planning on getting Graham´s mode shitching for the green channel so i will try it more then with an external switch to bridge r12 on the fly, is there any risk on doing it while operting the amp?

can i assume the same can be done for the clean mode on the corresponding resistor?, more or less what i´m looking for is to do the higher/modern gain and delay/chorus stuff on the clean with my ME50, classic rock (ACCD, Sabbath and the likes) on the crunch and heavier classic on the lead 1-2 when i can find a way to make them chunkier, i would like to have them as chunky as the crunch mode, so i´ll read the 11 pages to find out what to do, unless someone saves me the long read

How does R30 mod opposes to R12mod? doing both wouldn it be like making the lead 1 and 2 sound fantastic with the deep grit as Twin mentions but at the same time keep the crunch more or less same to stock and making it overall more plexierish?

Cheers

[el zilcho]

Hey, before I go on a jumper-clippering expedition...

Does anyone know how to get some real midrange in the clean channel?

[el zilcho]

So it looks like C4 (100pF) is the bright cap for the clean mode. C6 (1000pF) gets added in parallel to C4 when the crunch mode is engaged. Is this right?

I was thinking about swapping C4 and C6 so that the clean mode gets some more upper mids but the crunch mode will still sound the same. Not sure if that will get me the midrange I want or if the clean will be too bright after that. There might be a way to put a cap across the volume pot and tie one leg in with the mode switch...

[el zilcho]

Tried it, didn't like it. 1000pF doesn't bring the corner freq low enough. Just made the clean mode quacky.

What I really need is to bring up the ~500hz range.

[Joey Voltage]

Originally Posted by el zilcho

Tried it, didn't like it. 1000pF doesn't bring the corner freq low enough. Just made the clean mode quacky.

What I really need is to bring up the ~500hz range.

I'll help you with the clean thing, but It wont be until later, I'm not on my computer right now.

[TwinACStacks]

If Anybody can Help You El Zilcho, it's Joey. After all the Mod is Named after him.

TWIN

[Joey Voltage]

Okay Zilcho put everything to stock, on the pot board increase R2 to 56K, and C2 to .01uf that will give you more mids for your clean. If you need more, and like the frequency, increase R2 to 100K, and C2 to .0047uF. You will also notice a slight gain boost/volume increase.

[el zilcho]

Okay I put C4 and C6 back to their original values. I didn't have a 56k lying around so went ahead and tried the 100k and .0047uF for R2 and C2.

This seemed to just add a lot of low end and gain. The stock values were .047uF for C2 and 10k for R2, is that right?

[Rogue]

Hey fellas! I'm a new happy DSL50 owner. I've read through most of this thread. I knew I'd be doing some modding to it to tailor to my wants and needs, and that's cool. It's a great base!

It needed new tubes so I ordered up all of them. After I give that a go for a while and determine what I want to do with it, I'll be asking you guys lots of stupid questions! Just a heads up.

Rocking amp!

[rockback]

LOL Maybe I'll feed my ipod into it and walk away for a day

[Rogue]

Ok guys, I have a question. I've spent some quality time with my amp. I have have noticed on the red channel a top end sound that drives me nuts. I've experienced this sound on other amps. I call it a "wirey" sound because that's the word that describes it best to me. It might be considered sizzle by others as it kind of sounds like that, but I don't know if we are talking about the same thing. I would also call it "thin", but may not be an accurate description. It doesn't matter whether I turn the treble and presence down, it still has that sound just with less treble.

It's just an unnatural, sharp, "wirey" kind of sound. Hard to describe really. It goes away somewhat as the volume increases. I had the same issue with my 1959x. That same wirey sound. I clipped the bright caps on the board and it sounded much better. I think I ultimately just changed the value.

I stumbled across this thread....

JCM 2000 DSL (Page 3) - Joe's Guitars, Amps and Gear - Joe Bonamassa Official Message Board

I believe this guy experienced what I am experiencing now. mantegna said he did the "C12 mod" (apparently clipped a cap out of the circuit) and he as very happy with it.

It is also (assuming everyone is talking about the same cap) in the list of mods in this thread. "C12 Lower to 150pf or REMOVE (I removed it)"

So, does this do something similar to clipping the bright caps on 1959x (seems like they were C17 and C18 or something like that)? On the 1959x, the mod made the amp less aggressive, but made it more natural sounding and more musical, IMO. I'd like to do the same with the DSL. I'll likely find a value that works best for my normal playing conditions to keep it somewhat aggressive, but still more natural.

I'll get my new tubes tomorrow. They might take care of, but I have doubts they will.

Is this the right tree to be barking up? Are there any other mods that might help address this top end wirey sound?

[el zilcho]

There are a bunch of different things you can do. It really depends on if you're just trying to get rid of "fizz" (the really high frequencies that are mostly noise up above 6khz), or if you're wanting to change the upper midrange voicing of the amp.

Two things I would consider before you mod it:

1. The bright cap (C12) has less and less of an effect the higher the gain is set.
2. When you change the upper voicing of your amp, listen to it off-axis as well as on. What may sound perfect standing straight in front of the amp may end up sounding like it's under water if you take a step to the side (how the majority of people in an un-mic'd venue will hear it) or play it in the context of a drummer with loud cymbals.

-Clipping C12 on the pot board will get rid of most of the fizz and also take away the upper midrange bite that the cap adds.

-Lowering C12's value from the stock 470pF will reduce the upper mids more or less depending on how much you decrease the value. It will also reduce the fizz slightly.

-Increasing the value of C9 on the tube board will roll off the top end and get rid of the fizz. Using 1000pF rolls off highs at 3.2khz. This effects both the clean and dirty channels. I found that this was a little too dark on the clean channel so I went with 560pF for a roll off at 5.7khz.

-For a high end roll off on just channel B, you can attach a capacitor across the wiper and ground of the channel's volume pot like this:http://local.anchorstates.net/images/tsl/vr2-47pf.jpg. 68pF will roll off around 5.1khz, or you can use 100pF for a 3.5khz roll off.

[Rogue]

Thanks el zilcho. Yes, I understand I will aslo that I'll loose other frequencies to get rid of the fizzies. If there is a way of getting rid of the fizzies without loosing some of the upper mids, that'd be great. As I understand it, a capacitor doesn't just cutoff at a certain frequency but is linear...which means it's going to get into other areas we might not want.

I suppose that is the price of fizzy removal.

I doubt I'll be using a great deal of gain ever on the red channel. Probably 1 o'clock is as high as I'll go. No amount of off axis gets rid of these fizzies.

That is some great info. I haven't really noticed any 'fizz' on the green channel, but it wouldn't hurt my feelings to help fatten it up a little and give it a little more naturalness.

I think I'll start with C9 on tube board and see where that leads. If I get somewhere cool on the green channel, but the red still needs some top end taken off, I can still tweak C12, right?

On the green channel, do you use it in crunch mode or clean? Crunch mode has a lot of bottom end and I'm curious if changing C9 pronounces that even further.

[Rogue]

And I also found this...

DSL 100:C17 Treble bleed cap/MM OT questions?

For a noticeable tonal change (warmer tones) you must replace C16 on THE MAIN BOARD (if your amp was built in 2005 or after - pcb JCM2 60 02 -, C12 if before).

Mine is a 2006, is this information correct?

I don't know what my board numbers are. I'll find that out tonight.

[el zilcho]

I'm not sure about the board change. The bright cap will be next to R19.

Honestly, I would just try a 68pF cap on the channel B volume pot first. That will get rid of most of the fizz and not make the channel overly dark. The upper mids won't change and channel A won't change.

[Joey Voltage]

Originally Posted by el zilcho

Okay I put C4 and C6 back to their original values. I didn't have a 56k lying around so went ahead and tried the 100k and .0047uF for R2 and C2.

This seemed to just add a lot of low end and gain. The stock values were .047uF for C2 and 10k for R2, is that right?

try decreasing the value of the cap, if you notice, you are only really dealing with a fixed tone network in that area, which is gain dependent.

[Rogue]

Originally Posted by el zilcho

I'm not sure about the board change. The bright cap will be next to R19.

Honestly, I would just try a 68pF cap on the channel B volume pot first. That will get rid of most of the fizz and not make the channel overly dark. The upper mids won't change and channel A won't change.

Thanks. I'll give that a try first. I'd like to affect the mids as little as possible.

[el zilcho]

I left the 100k in R2 and tried decreasing C2. The more I decreased C2, the more bass and gain I got. Going back to .047uF brought the bass back to where it was. I tried a 4.7uF to see what that would do, but it didn't sound much different than .047uF.

Now that the bass is under control, I can hear how that 100k is adding a decent amount of mids. It sounded kind of muffled though, so I paralleled a 560uF with C4 and it opened it up nicely.

I'll mess around with it more when I get some time.

[Joey Voltage]

Originally Posted by el zilcho

I tried a 4.7uF to see what that would do, but it didn't sound much different than .047uF..

It won't, because you are passing most of the audible limit at that point. The 100K IS what is doing the work of increasing the mids, not the cap. I mentioned the cap in order to tailor the upper limit of the bass in order to include frequencies above 500hz, but yes, added gain and muddiness might (and seems to be) a side effect, if we cant limit the lower bass spectrum somewhat, treble can be easily increased as well. I will take another look at the scheme.