Join Date: Nov 2003
Location: North Adams, MA
Got my amp back (JCM 900 SL-X mod!)
Well I got my amp back. Had a Marstran '68-'80 era Marshall spec transformer [C1998] installed and the gain toned down a little.
All new tubes, SED "Winged C" EL34s in the poweramp, and for the preamp I got both 4 RFT ECC83s and 4 Amperex ECC83s and tried them both. I found the RFTs to be meaner but the Amperex's were higher gain overall and I got better power side distortion from the Amperex's so I went with them (the RFTs will be split between the Vox and Studio 15).
It's absolutely sick! I get a wide variety of new sounds from it as well as the old but only better. One of the tones I can nail is Bad Horsie as well as more typical Marshall tones like Iron Maiden, Judas Priest, etc.
Also previously, it wasn't usable with the master volume below a certain point, usually 5 but varied depending how loud I turn the preamp up to, and now it sounds good at lower volumes as well. Still not much of a clean tone, but it opens up a whole new world of distorted sounds!
I'd recommend the same thing to any other SL-X users. The transformer swap should help out with any new Marshall as well.
I'll post some clips when I get my BKPs.
Last edited by red5; 06-06-2006 at 03:59 AM.