Ibanez JEM Forum banner
1 - 17 of 17 Posts

·
Premium Member
Joined
·
2,851 Posts
Discussion Starter · #1 ·
I'm on a roll with new posts, so humor an old man........

I just had some work done to my main Marshall head: it's a 1990 JCM900 Dual-Reverb 4500 model and I've always liked them over the older 800's because of TWO real channels ( and of course, verb).

I was telling Dankynugs recently that I changed out the pre-amp tubes to original, real NOS Mullard 12AX7 tubes. These are expensive, rare and sought after. If you happen to see them for sale and they are real -BUY THEM.
Definitely the single biggest change you can make to your amp.

THEN...I took a deep breath and had a Mercury Transformer kit put in.
I spoke with many techs and asked lots of questions because I've never done that mod before- and HOLY COW does it make a difference. Even a 2-year old kid will notice the difference- it's not a subtle change. More SAG, more power & crunch- and now you really hear finger and string definition.

Anyway - thought I'd share:^)
-jemaholic
 

·
Registered
Joined
·
1,076 Posts
Yeah, been scouring for a Mullard or two, lately. Keep getting outbid. From all that I've read and been told, they are the Holy Grail of tubes. Congrats on the mods!
 

·
Registered
Joined
·
152 Posts
anyone have any experience modding a tsl100 parallel fx loop?? its never 100% wet kinda annoying

wana get a series loop in there
 

·
Registered
Joined
·
359 Posts
I have the model 4100 JCM900 and the last time I had it re-tubed/biased I used sovteks and I liked them better than stock. Where can I get more info on this mercury transformer kit?
 

·
Registered
Joined
·
1,923 Posts
now, anyone know any mods for the MG100 HDFX?

i kid... i kid...
Well.. I can tell you that replacing one of the two diode clipping pairs with either an LED or a 1n4001 will give it some more character. When I was still managing a guitar shop, me and one of the other guys I worked with took apart the MG mini stack when the boss wasn't around. We found that changing one of the two clipping diodes actually produced an improvement. Changing boths caused crazy amounts of noise.

I honestly still want to buy myself one of those mini stacks to gut out and replace with a mini 18w tube head or something.

I'm actually tempted to buy a cheap HDFX and gut it out with a hand wired plexi clone or something.
 

·
Registered
Joined
·
1,076 Posts
I'm actually tempted to buy a cheap HDFX and gut it out with a hand wired plexi clone or something.
That would be a cool idea, especially to rope people in. Imagine some gear snob scoffing at your "rig", when you turn it on, and crank it out. One of two things would happen:

1 - His jaw would hit the friggin' floor.

-or-

2 - He would still stick by his "your tone sucks, cause it's an HDFX" attitude, in spite of the killer tone, present, all the while being clueless of what it REALLY is, and showing him for the jackass that he truly is.

Either way, you get a good chuckle out of it. :mrgreen:
 

·
Registered
Joined
·
1,923 Posts
That would be a cool idea, especially to rope people in. Imagine some gear snob scoffing at your "rig", when you turn it on, and crank it out. One of two things would happen:

1 - His jaw would hit the friggin' floor.

-or-

2 - He would still stick by his "your tone sucks, cause it's an HDFX" attitude, in spite of the killer tone, present, all the while being clueless of what it REALLY is, and showing him for the jackass that he truly is.

Either way, you get a good chuckle out of it. :mrgreen:
You got that right! I'm hoping that the day I do that, the guy's jaw will hit the floor but still think my tone sucks 'cause it's an HDFX. You know there's at least ONE guy like that at practically every gig. Seeing that it's a $#!TTY solid state HDFX, I doubt he'd ever figure out that someone would have gutted it out or even think that I 'modded' a solid state amp, 'cause who the hell does that?!?

Damnit, now I really wanna pull this off. Of course I'd also have to have the most UN-shred & Un-Metal guitar like a big jazz-body but with some awesome pickups(with aged scratched up nickel covers so it looks stock).
 

·
Registered
Joined
·
352 Posts
I'm on a roll with new posts, so humor an old man........

I just had some work done to my main Marshall head: it's a 1990 JCM900 Dual-Reverb 4500 model and I've always liked them over the older 800's because of TWO real channels ( and of course, verb).

I was telling Dankynugs recently that I changed out the pre-amp tubes to original, real NOS Mullard 12AX7 tubes. These are expensive, rare and sought after. If you happen to see them for sale and they are real -BUY THEM.
Definitely the single biggest change you can make to your amp.

THEN...I took a deep breath and had a Mercury Transformer kit put in.
I spoke with many techs and asked lots of questions because I've never done that mod before- and HOLY COW does it make a difference. Even a 2-year old kid will notice the difference- it's not a subtle change. More SAG, more power & crunch- and now you really hear finger and string definition.

Anyway - thought I'd share:^)
-jemaholic
any chance of doing some sound clips? would be interested to hear the beast in action :p
 

·
Premium Member
Joined
·
2,851 Posts
Discussion Starter · #12 ·
any chance of doing some sound clips? would be interested to hear the beast in action :p
We have some big gigs coming up this summer which will be recorded directly off the mixing board. I'll throw them up on the site....
 

·
Registered
Joined
·
63 Posts
Some great topics being discussed on this thread. Most of the sound of a marshall is the transformer and tubes( El 34s). The sound of a marshall is unmistakable: the puchiness and articulation. We've all heard the over distorted/ compressed/fizzy sound of too much preamp gain...Mesa Boogie comes to mind as do the terrible rack sounds of the early eighties(too much processing/solid state power amps). Tube heads work as complete units; compare the sound of a Mesa triaxis/tube power amp to a dual rectifier or Mk IV -its not even close. Your upgrade makes perfect sense.
The issue of the effects loops on Marshalls: anything you put in an effects loop is going to change your sound. I've never had a marshall with a good loop and I've owned a few(early 800, Silver Jubilee 100 watter, Slx 900, Splawn Jmp). Its a common problem is amps whose sound is based on the output section-the loops in Soldanos are useless too The best solution is to mike your cab and run your effects thru the pa -No signal or tone loss issues-unfortunately you're at the mercy of the soundman. The Custom Audio Electronics heads and the Bogners have great loops.
 

·
Registered
Joined
·
1,076 Posts
You got that right! I'm hoping that the day I do that, the guy's jaw will hit the floor but still think my tone sucks 'cause it's an HDFX. You know there's at least ONE guy like that at practically every gig. Seeing that it's a $#!TTY solid state HDFX, I doubt he'd ever figure out that someone would have gutted it out or even think that I 'modded' a solid state amp, 'cause who the hell does that?!?

Damnit, now I really wanna pull this off. Of course I'd also have to have the most UN-shred & Un-Metal guitar like a big jazz-body but with some awesome pickups(with aged scratched up nickel covers so it looks stock).
Go one step further, and do it with one of those Hello Kitty Squiers, with a killer bucker! REALLY make em piss his pants! hehe.
 

·
Registered
Joined
·
1,081 Posts
Well.. I can tell you that replacing one of the two diode clipping pairs with either an LED or a 1n4001 will give it some more character. When I was still managing a guitar shop, me and one of the other guys I worked with took apart the MG mini stack when the boss wasn't around. We found that changing one of the two clipping diodes actually produced an improvement. Changing boths caused crazy amounts of noise.

I honestly still want to buy myself one of those mini stacks to gut out and replace with a mini 18w tube head or something.

I'm actually tempted to buy a cheap HDFX and gut it out with a hand wired plexi clone or something.
I run my hot-rodded Epi Valve Junior 5-watt head through a power soak and into my Marshall Mini-Stack--my friends freak out when they hear the crunch, tone, and responsiveness coming out of that rig!
 

·
Registered
Joined
·
70 Posts
Hey Bud, Ive got one of the HDFX 100 half stacks in the Special Edition Red if youre interested. Funny, I was just thinking of getting rid of it. Pm mw if interested.
 
1 - 17 of 17 Posts
Top