Author Topic: Got my amp back! (JCM 900 SL-X MOD!) (Read 8115 times)

fps_dean · « **on:** June 06, 2006, 01:54:53 AM »

I got my JCM 900 SL-X back. Had a Marstran '68-'80 spec transformer (C1998) installed and the gain toned down a bit, and new tubes.

Now it sounds just like one of Lee Jackson's modded '69-'74 era Marshalls. One of my tones is Steve Vai's Bad Horsie to a pinpoint, but I can do more standard Marshall sounds like Iron Maiden, etc. Still not much of a clean tone, but I'm getting a lot of really killer distorted tones from it ;)

Will record some clips when I get the BKPs!

chrisola · « **Reply #1 on:** June 06, 2006, 06:57:17 PM »

less gain eh?

Pfft get out :P

Sounds like a great amp, look forward to some juicy clips 8)

fps_dean · « **Reply #2 on:** June 06, 2006, 07:11:30 PM »

Quote from: chrisola

less gain eh?

Yeah it still has a lot of gain to it though, and before I would never come close to maxing it out. This gets me more poweramp distortion, as well as a little more headroom.

JamesHealey · « **Reply #3 on:** June 07, 2006, 08:43:50 AM »

SL-X's have enough gain as it is.

fps_dean · « **Reply #4 on:** June 07, 2006, 08:57:03 PM »

Quote from: JamesHealey

SL-X's have enough gain as it is.

Thank you, at least someone understands why I had the gain taken down a notch ;)

Not only did it improve the tones I get significantly, but I can now get the classic overdriven Marshall tones as well as more modern modded Marshall tones as well. I am so loving this amp right now...

BleedMarshall · « **Reply #5 on:** June 08, 2006, 02:13:35 PM »

Good deal. Would love to hear the clips of it.

fps_dean · « **Reply #6 on:** June 08, 2006, 06:55:25 PM »

Quote from: BleedMarshall

Good deal. Would love to hear the clips of it.

I'm just waiting to have my BKPs installed in my Les Paul. I was going to do it myself ... I actually had the neck pickup good to go minus the ground, but I actually got two push pull pots for coil splitting and the shafts pulled right out of both of them, I didn't even pull on them hard. When I removed the bad pots, the wires from the switch broke off, and left not enough room to strip it.

I'm just going to have someone else fix it at this point. I'm not going with small stuff like that and it was just pissing me off to begin with.... :(

Bainzy · « **Reply #7 on:** June 08, 2006, 07:17:02 PM »

Sweet - from what I've heard Brian's transformers are top notch, and the 1.5" C1998 Dagnall is a great model (the best for rock in my opinion).

fps_dean · « **Reply #8 on:** June 08, 2006, 10:33:41 PM »

Quote from: Bainzy

Sweet - from what I've heard Brian's transformers are top notch, and the 1.5" C1998 Dagnall is a great model (the best for rock in my opinion).

That's what I thought. I was thinking of getting a C2668 (I think thats the correct number?), the JCM 800 one but then I thought about it and with 4 preamp tubes, the tone will be bright enough. The C1998 is well balanced and aggressive, sort of the best of both worlds.

I asked people at the forums over at plexipalace.com whats a good transformer these days, and literally everyone recommended Marstrans.

I brought the guitar to the shop today - should have my BKPs installed sometime in the middle of next week!

HTH AMPS · « **Reply #9 on:** June 08, 2006, 11:39:46 PM »

Quote

Thank you, at least someone understands why I had the gain taken down a notch Wink

Not only did it improve the tones I get significantly, but I can now get the classic overdriven Marshall tones as well as more modern modded Marshall tones as well. I am so loving this amp right now...

its certainly a balancing act getting alot of gain & retaining good tone too - I tweaked my own homebrew high-gain amp for around 6 months on/off to get it where I like it now. I actually cut back on the gain a little compared to some schematics I have with a similar circuit topology.

glad you like the SL-X now, be sure to post some clips with the BKPs.

:twisted:

fps_dean · « **Reply #10 on:** June 09, 2006, 06:47:02 AM »

I liked it before too, but it's just so much better now ;)

I should have the BKPs installed mid-next week. Now the trick is to get some day time hours off of work, which I believe is easy next week.

HTH AMPS · « **Reply #11 on:** June 09, 2006, 01:53:23 PM »

upgrading the OT to the Marstran one you got will yield a big improvement by itself - the other preamp mods will zero in on the tone to take away the OTT gain. I'd imagine there will be a very noticeable improvement in that amp (I've got SL-X gas now damnit!!!) :lol:

:twisted:

BleedMarshall · « **Reply #12 on:** June 09, 2006, 01:53:58 PM »

Quote from: fps_dean

Quote from: BleedMarshall
Good deal. Would love to hear the clips of it.

I'm just waiting to have my BKPs installed in my Les Paul. I was going to do it myself ... I actually had the neck pickup good to go minus the ground, but I actually got two push pull pots for coil splitting and the shafts pulled right out of both of them, I didn't even pull on them hard. When I removed the bad pots, the wires from the switch broke off, and left not enough room to strip it.

I'm just going to have someone else fix it at this point. I'm not going with small stuff like that and it was just pissing me off to begin with.... :(

I hate when things break like that. Just leaves you discouraged and too mad to do the job right afterwards. No worries. I am patient. :lol:

fps_dean · « **Reply #13 on:** June 10, 2006, 04:02:44 AM »

Quote from: HEAVIER THAN HELL

upgrading the OT to the Marstran one you got will yield a big improvement by itself - the other preamp mods will zero in on the tone to take away the OTT gain. I'd imagine there will be a very noticeable improvement in that amp (I've got SL-X gas now damnit!!!) :lol:

:twisted:

Yup there are. The mids are very smooth now. Sounds very similiar to the mids on my '69 Major (part if it is my Classic Lead cabinet too though), but with more gain. I think a modded '59-'74 era 1959SLP similiar to Steve Vai's is the best way to describe it ;)

fps_dean · « **Reply #14 on:** June 10, 2006, 04:05:51 AM »

Quote from: BleedMarshall

I hate when things break like that. Just leaves you discouraged and too mad to do the job right afterwards. No worries. I am patient. :lol:

You don't even know I was ready to break something when that happened. I barely have money to get this fixed. Of course, if I could soldier better it may help, but part of the problem was the last time I put pickups in, the soldier was cr@p and even with a 65 watt stained glass soldiering iron it was hard to melt that shite.