Metropoulos Forum

paulster wrote: The Levi amp was built as an exact tonal copy of #39, such was the demand for #39 as a rental amp.

slashsound wrote:

paulster wrote: The Levi amp was built as an exact tonal copy of #39, such was the demand for #39 as a rental amp.

This cant be true, maybe similar but not exact.

slashsound wrote:I got this Email from Tim Caswell, the original designer of the #39 from which Frank Levi derived the number #36.

He writes:

I had a link to a website that I have since lost, where Frank Levi described
what he thought he had done on #36, altho he said it had 2 preamp
controls, which is not how other people remember it.

Although #39 had been S.I.R.’s number one amplifier for almost as long as Glenn had been there, George Lynch’s rental of the amp in early 1986, in particular, served as an important turning point for Glenn and others at S.I.R.. First of all, the intense reaction to #39 by a player of George’s caliber was even further validation of the amp’s special and unique qualities. Secondly, and most significantly, when George rented #39 from early January through mid-March 1986, the amp was sorely missed by S.I.R. and its customers during this fairly long-term absence.

Glenn recognized that S.I.R. simply wasn’t able to meet its customers’ demand with only one amp that sounded the way #39 did. The decision was made to modify a couple of other Marshalls to serve as “substitutes” for #39 for times when the amp was being rented out or routine maintenance was being performed to it.

One of the earliest of these experimental “substitutes” for #39 was Stock #36, which was modified in Spring 1986. The modifications to #36 were performed by Frank Levi (who had just recently been hired by S.I.R. as Tim Caswell’s replacement) in conjunction with Glenn. The two men collaborated on the project, with Frank doing most of the physical modification work.

Frank was very skilled and experienced when it came to all sorts of tube-based gear. When Frank first started work at S.I.R. in Los Angeles, Glenn introduced him to #39. After taking a listen and a look inside #39, Frank was very impressed with Tim Caswell’s work. When Glenn spoke with him about making “more #39s,” Frank was able to make it happen. Frank and Glenn both agreed that #36 was a good test subject to begin their tinkering.

Like #39, #36 was a 100W pre-master volume, “Metal Panel“-era (early ’70s) Marshall. However, while #39 was a Super Tremolo, #36 was a regular (non-tremolo) Super Lead (Model 1959). As such, because #36 didn’t have a tremolo circuit, the amp didn’t have a fourth pre-amp tube as a stock feature. Therefore, when Frank and Glenn applied Tim Caswell’s #39 extra pre-amp gain stage design to #36, an additional (fourth) preamp tube was mounted in a hole drilled next to the original (three) pre-amp tubes.

Frank and Glenn also did some additional tweaking to #36. Specifically, through trial and error experimentation, the switched out certain stock capacitors and replaced them with others obtained from vintage “donor” amps, including some old Fenders, until they were satisfied with the results.

As far as other physical and cosmetic characteristics are concerned, Glenn recalls that #36 had the small, “classic” Marshall logo on the front. The amp had “36” stenciled in white, one-inch numbers on each end (whereas two-inch stencils were used on #39). “S.I.R. LA” was stenciled along the top of the back of the amp (also in one-inch letters), with S.I.R.’s phone number below that. The amp was in fairly good condition for its age at the time.

Another interesting variation between #36 and #39 was that the modification to #36 was always “on.” Whereas #39 had a metal toggle switch mounted in place of one of the amp’s four input jacks (which was used to turn Tim Caswell’s mod on and off), the modification to #36 did not include a toggle switch or any other mechanism to turn the mod off. In fact, to someone looking at the outside of #36, the only perceptible modification would have been the addition of a master volume knob. Even this master volume control would only have been noticeable to the trained eye, since it was done in such a manner as to preserve the amp’s otherwise stock appearance.

paulster wrote:
If you're dead set on this quest then you probably want to get hold of MisterMiniMite and, from him, get hold of Glenn Buckley since he would have the same information.

RACKSYSTEMS wrote:So Slash has a amp that has appeared on most of the records that was modded by Frank Levi and I just worked on it. I can only imagine that this is the same mod. So I know what it is. By the way it is #34 sir amp.

RACKSYSTEMS wrote:So Slash has a amp that has appeared on most of the records that was modded by Frank Levi and I just worked on it. I can only imagine that this is the same mod. So I know what it is. By the way it is #34 sir amp.