Slash Appetite amp - concluding article

I've been messing around putting this article together, on and off, for months now. I figured, what the hell, it's not perfect, not 100% polished, but the information is the most important thing... Sorry for the delay Special thanks to Glenn Buckley for all the great information (and for reviewing this draft for accuracy!).

Sweet Marshall O’ Mine Part 2: The Breakthrough - Case Closed!

You might recall my article titled “Sweet Marshall O’ Mine?: The Untold Story of S.I.R. Stock #39,” which appeared in Guitar Digest’s June-July 2005 issue. If you don’t, here’s a recap of the pertinent facts:

In late 1985, during rehearsals following the November 1985 release of Dokken’s “Under Lock And Key” album, George Lynch rented a modified Marshall head from S.I.R. (Studio Instrument Rentals in Los Angeles). The amp was a 100W Marshall Super Tremolo (Model 1959T) - a hand-wired, pre-master volume model of the “Metal Panel” (post-“Plexi”) variety (manufactured sometime between mid-’69 and mid-’73). George was so “blown away” by this “perfect amp” (George’s words - not mine) - known to S.I.R. as “Stock #39 - that he desperately tried to convince S.I.R. to sell it to him. After S.I.R. refused to sell #39 or even reveal the name of the person who had modified the amp, George paid approximately $2,000 just to rent the amp for the first leg of Dokken’s tour in early 1986.

Upon returning #39 to S.I.R. following his rental of the amp, George finally learned the name of the mystery modifier who had performed the modification to #39: Tim Caswell (Tim had worked in S.I.R.’s tech/service department for several years until 1985, when he left S.I.R. just prior to George’s rental of #39). Subsequently, George contacted Tim in order to have a handful of his own Marshalls similarly modified.

In short, Tim’s modification to #39 consisted of utilizing the amp’s then-unused tremolo circuit (with its additional pre-amp tube) to hot-rod the Marshall by adding an extra pre-amp gain stage. A master volume control was also part of the modification to #39, since the amp was a pre-master volume model.

Switching gears to another famous guitar player and S.I.R. amp rental customer, my original article stated that, contrary to popular belief, Slash did not use a 1987 Marshall Silver Jubilee model during the recording of “Appetite For Destruction.” In fact, this would have been impossible. “Appetite” was recorded between August and December 1986. The Jubilees were not manufactured and shipped until 1987.

My article went on to document how Slash has also spoken about his affection for a “magic” Marshall head (Slash’s word - not mine) that he rented from S.I.R. and used heavily during the “Appetite” studio recording sessions. After the “Appetite” recordings had concluded, Slash told S.I.R. that the amp had been stolen so that he wouldn’t have to return it. Slash kept the amp for a while until his roadie at the time made the mistake of bringing the amp to rehearsals at S.I.R. following the release of “Appetite” in 1987. When the guys at S.I.R. recognized their amp, they took it back.

My article made the argument that, given the chronological and other circumstantial evidence available (as well as the lack of any substantive and reliable evidence to the contrary), it was reasonable to conclude that the George Lynch S.I.R. Marshall and the Slash S.I.R. Marshall were one and the same.

Since the time of my article’s appearance in Guitar Digest, my research into the topic of Slash’s “Appetite” amp has continued. In fact, the publication of my article gave me the “credibility” I felt that I needed to take my research to the next level. After all, I was no longer just some dude obsessed with gear and “Appetite” - I was some dude obsessed with gear and “Appetite” *who had written an article that had appeared in a magazine.*

Emboldened by my newfound sense of legitimacy, I began a wide-ranging campaign to attempt to track down and contact everyone I could possibly think of who might have even the slightest knowledge about the subject. Through dozens of weekend letters, late-night e-mails, and lunch-time phone calls (most of which receiving no willing repliers), I was able to get in touch with many interesting and knowledgeable people with various potential connections to the subject. However, despite all the fun I had while following up on all of these potential leads, most of my efforts resulted in dead ends when it came to learning actual historical facts, and I was beginning to get discouraged.

Finally, a *major* breakthrough occurred.

Before I get into this new information, recall the following key excerpt from an April 1987 interview with George Lynch in Guitar For the Practicing Musician (as contained in my original article):

"For the first album I used old Marshalls, which I'd used for years. Then I tried the Randalls and was happy with them for a while. Then I went to Laney and back to Marshall. I was using Lee Jackson Metaltronics, which is what Vai is using. I also used the Jose modified Marshalls for a while. Now I'm using Tim Caswell modified Marshalls. What happened was that I went into S.I.R. and rented an amp. It sounded amazing. It was the perfect amp. You just plug in and it was all there. I went to the guy and said I've got to have this amp. It got to the point where they were calling the owner of S.I.R., who was on vacation, and I was offering him three Marshall heads in trade or $2,000, whatever they wanted. They wouldn't sell it. They said it was their number one amp. Everybody who came in requested it. I ended up renting it for the whole Twisted Sister tour, which cost me about $2,000. Eventually I had to give it back. I had all kinds of schemes in mind. I thought I'd take all the guts out of the brain and put in different guts. I couldn't do that. Eventually one of the repairmen told me the guy's name who did the modification. I called the guy and he did one for me. Now he's done six for me. He is amazing…"

Aside from my actual communications with Tim Caswell, this particular George Lynch interview excerpt was probably the single most important piece of information that I had been able to identify early on in my “investigation.” In effect, this April 1987 interview was the original basis for my knowledge of George’s rental of #39.

One sentence, in particular, had always intrigued (and frustrated!) me:

“Eventually one of the repairmen told me the guy’s name who did the modification.”

Every time I would read this sentence, it always *killed* me that there seemed to be this one “repairman” at S.I.R. after Tim Caswell left in 1985 who: (1) had this type of detailed knowledge about #39 and who had modified it, and (2) had this level of direct interaction with high-profile players such as George Lynch.

While nobody knew for sure who this “repairman” was that George Lynch had referred to, Tim Caswell and other former S.I.R. guys had mentioned the name of one particular former S.I.R. employee whom they felt might be the only person on earth with the type of knowledge I had been seeking for so long. They universally agreed that this one person would be, hands-down, the key to unlocking the mystery of the Slash “Appetite” amp once and for all. His name was Glenn Buckley.

The only problem was, nobody had any idea where Glenn was, or how to contact him. In fact, I wasn’t even sure about the exact spelling of Glenn’s first name (was it “Glenn” or “Glen”?), let alone his last name (“Buckley” or possibly the less common “Buckly”)! The last time that Tim Caswell had spoken to Glenn was in 1986. One of the former S.I.R. guys with whom I had been speaking, Jamie Muntner, knew that Glenn had gone on to work at Alesis in Los Angeles after he left S.I.R., but Jamie had lost touch with Glenn after that. I called Alesis, but the bulk of their California operations, including their corporate headquarters, had fairly recently been moved to Rhode Island.

Finally, I found some contact information for a “Glenn Buckley” who seemed to live and work in the greater Los Angeles area, and I called him up. I was *thrilled* to find out that he was the same Glenn Buckley who I had been dying to reach for so many months.

As it turns out, *Glenn* was the mystery S.I.R. “repairman” that George Lynch had referred to in his April 1987 interview!

From early on during my first conversation with Glenn, I quickly learned that Glenn was, without question, the “missing link” and encyclopedic resource that I had been dreaming about. He immediately recalled intricate details about #39 and the other Marshalls in S.I.R.’s rental inventory during the mid-to-late ‘80s. Most important of all, Glenn vividly remembered all of the key facts and details about Slash’s “Appetite” S.I.R. amp rental.

Glenn moved to Los Angeles from Vancouver, British Columbia in June 1984 and began working at S.I.R. in September 1984 just weeks prior to his 25th birthday. He worked as the manager of S.I.R.’s quality control department for about five years and left the company in August 1989. Glenn worked closely with Tim Caswell for over a year until Time left S.I.R. in 1985. In fact, Glenn even recalls how Tim first demonstrated the newly-modded #39 to him in late 1984 (believed to have occurred around December 1984).

As stated above, Glenn was the mystery “repairman” who finally told George Lynch that it was Tim Caswell who had modified #39. Dokken’s “Under Lock And Key” album was released in November 1985. George Lynch and Dokken had been rehearsing in December 1985 for their upcoming tour when George first discovered #39. Glenn was at the center of the action as George tried in vain to buy #39 and when George eventually settled for renting the amp for the first leg of Dokken’s upcoming tour.

Recent research has revealed that the first leg of Dokken’s tour (which was the U.S.-based portion, with Twisted Sister) began in early January 1986 and concluded with a show in Indianapolis on March 10, 1986. It is believed that George Lynch returned #39 to S.I.R. in mid-March 1986, in the days following the Indianapolis show. This is when Glenn finally mentioned Tim Caswell’s name to George, and George was able to first make contact with Tim.

Meanwhile, Guns N’ Roses signed with Geffen Records within days of all of this, on March 25, 1986. Shortly after signing Guns N’ Roses, Geffen paid for Guns N’ Roses to rehearse at S.I.R. during the Spring of 1986 in order to give the band the opportunity to work on their songs before going into the studio to record their debut album.

Glenn recalls reviewing the S.I.R. equipment rental contract for these pre-“Appetite” rehearsal sessions. At the time, Glenn wasn’t familiar with Guns N’ Roses, who were one of many new Los Angeles area bands of the day. Therefore, Glenn didn’t have any basis for anticipating the sound that Slash would have been aiming for with respect to amplifiers. Consequently, at the start of these pre-“Appetite” S.I.R. rehearsals, Glenn brought down a selection of several Marshall heads from S.I.R.’s rental inventory for Slash to try out. Slash’s choice was clear right off the bat: #39. In fact, Glenn is not the only former S.I.R. employee who recalls how Slash insisted on using #39 during these Spring 1986 pre-“Appetite” rehearsals. It is clear that #39 was the only amp in S.I.R.’s rental inventory that would “do it” for Slash at the time.

A few months later, in the Summer of 1986, Glenn recalls reviewing a second S.I.R. equipment rental contract (again, with Geffen Records footing the bill). This second contract called for the long-term rental and delivery of an amp to the studio for the Guns N’ Roses recording sessions (for the album that would become “Appetite”). The contract specifically listed #39 as the amp to be delivered.

Glenn’s heart sank a little bit as he read the contract, since he had just recently rented #39 to another S.I.R. customer, and the amp would be unavailable during the rental time period set forth in the contract. Glenn hadn’t been kept in the loop about when the Guns N’ Roses studio sessions were scheduled to begin. If he had known this information in advance, he might have been able to plan for it by setting the amp aside. In light of the fact that #39 was S.I.R.’s most in-demand amplifier at the time, unless specific arrangements were made clear to Glenn well in advance, Glenn handled requests for the amp on a first come, first served basis.

In any event, S.I.R. still had to deliver an amp, and Glenn soon had a good plan.

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.

Anyway… getting back to our story about #39 not being available for the “Appetite” studio recording sessions when the amp was specifically requested in the S.I.R. equipment rental agreement… you’ve probably already surmised that Glenn sent #36 to the studio instead. Thus, #36 was the amp that Slash used during the “Appetite” studio recording sessions.

By all indications, apparently, Slash was just as thrilled with #36 as he had been with #39. After S.I.R.’s delivery guys dropped the amp off at the studio, Glenn received no complaints or questions about it. At the conclusion of the “Appetite” studio recording sessions, #36 wasn’t returned right away, which wasn’t unusual, since it was pretty normal that some customers would need a little extra time with certain gear for overdubs and other similar reasons. Then more time passed and still #36 hadn’t been returned. Not only did Glenn need #36 back to rent to other S.I.R. customers, but Glenn started to get a bad feeling about his prospects for ever seeing the amp again. After about three months of the amp being overdue for return, Glenn had one of S.I.R.’s dispatchers call about it. At first, S.I.R. was told that Slash was still using #36 and that it would be back within a few weeks. Another month passed and S.I.R. called again. This time S.I.R. was told that the amp had been stolen.

Given the change of story and the preceding stalling tactics, Glenn had a gut feeling that Slash still had the amp. He alerted S.I.R.’s drivers to keep an eye out for #36, since the drivers were constantly all over town, at dozens and dozens of gigs and studios each week. Several months had passed, and still #36 had not been spotted. Glenn decided not to send a bill for cost of the amp to the record company since, in the event that they paid for it and later the amp showed up, Glenn wouldn’t be able to take the amp back.

In the Summer of 1987 (following the release of “Appetite” on July 31, 1987), Glenn got wind that Guns N’ Roses was coming into Stage 6 at S.I.R. to rehearse. [After doing some research into the history of Guns N’ Roses in 1987, I believe that these particular rehearsals might have occurred during the first two weeks of August 1987, just prior to Guns N’ Roses hitting the road as the opening act for the Cult; the first show with the Cult took place on August 14, 1987 in Halifax, Canada.] Glenn’s hopes rose slightly as he figured that there was at least a chance that he might get some info about what had happened to #36. If, in fact, Slash *did* still have #36, Glenn didn’t think that Slash would ever actually bring the amp to the rehearsals. Nevertheless, Glenn alerted the two S.I.R. guys that worked Stage 6 about the situation, and asked that they call Glenn personally if, by chance, the amp somehow showed up.

During the first days of these rehearsals, Glenn actually went down to Stage 6 himself, standing in the background and hoping to catch a glimpse of #36, but nothing came of it.

A few days later, while Glenn was working late one night, he was informed by the dispatcher on duty that #36 had just been spotted at Stage 6.

The dispatcher, knowing that the #36 issue was personal to Glenn, smiled and handed Glenn the keys to one of S.I.R.’s vans. Glenn asked a couple of the other drivers to come with him to act as witnesses, as well as to provide a little “extra muscle,” if needed. Glenn didn’t know if Guns N’ Roses would be at the stage or not, but it was his intention to walk in, grab #36 “with a smile,” and then simply walk out.

Glenn and the others got in the van and drove the short two blocks down to Stage 6 at Santa Monica Boulevard and Gower Street. They entered through a loading dock door. Glenn went over to the S.I.R. staff at Stage 6 and asked if the band was in. After being informed that that band wasn’t there, without any confrontation or fanfare, Glenn simply walked over to #36 and carried it back to the van, and then drove it back to S.I.R.’s main shop on Sunset Boulevard. Glenn hid the amp for the night in the back of the repair shop under a blanket and some other gear, and then went home, stopping by a local pub, The Cat and Fiddle, in quiet celebration of #36’s surprise homecoming.

Glenn never heard a word about Slash’s reaction to #36’s repossession, although he never asked anyone about how Slash took the loss of “his” prized “Appetite” amp. Glenn looked after the amp the best he could until the day he left S.I.R. in August 1989. At the time Glenn left S.I.R., both #36 and #39 were still available in S.I.R.’s rental inventory.

Then, of course, came the “Use Your Illusions Sessions”… but that is another story (and another amp) altogether!

oops double post

An amazing story. Slash has always been my favorite guitar player and I love his tone as much as his playing. I would love to know if those amps are still there.

itbepopples - I'm glad you liked it. To answer your question, I've been in touch with S.I.R. on multiple occasions over the past 10 months or so, and as far as I know, neither #36 nor #39 is in their rental inventory anymore.

So, Slash stole the amp head? Why now buy it? How cool is that? :wha

Brownsound said:

So, Slash stole the amp head? Why now buy it? How cool is that? :wha

Click to expand...

It wasn't for sale. Also those guys were for real... they didn't just make songs about being street urchins. They were real lowlifes!

Wow man. Cool story, thanks for posting all that.
As for Slash keeping the amp all that freakin' time... :toobad

Is Tim Caswell available to do the same mods to other Marshalls?
Thanks.

MisterMiniMite said:

itbepopples - I'm glad you liked it. To answer your question, I've been in touch with S.I.R. on multiple occasions over the past 10 months or so, and as far as I know, neither #36 nor #39 is in their rental inventory anymore.

Click to expand...

I wonder what could've possibly happened to them! I wouldn't want one of them but it would be nice to know where they are.

drspencer1 said:

Is Tim Caswell available to do the same mods to other Marshalls?
Thanks.

Click to expand...

Looks like lots of people are anxiously anticipating Mr. Caswell's work. Keep an eye on the Studio Electronics website and this might help you out.
CLICK ME!

from looking through caswell website his passions seem to not include guitar amps. i'm intrigued by the mystery sir #39 and #36 amps as well. my question is where is frank levy and is he working with guitar tube amplifiers ?

I'd also like to know the whereabouts of Frank Levi. The question is, where to go for the most likely approximation of that AFD mod: Tim, Glenn, or Frank? If only one does it, then that's the answer but if more than one can and would, what would be the pecking order?

As I posted in another thread, the "usual" Frank Levi mod is:

I've never gotten around to drawing this up, but if you are familiar with a typical Marshall MV preamp, this should make sense to you:

Input jack to first stage - 34k resistance (the two stock 68k's in parallel), or a 33k will do.

First stage cathode - 3.3k bypassed with 330mfd.

Out from first stage, through .022 into a 1 meg pot. Bypass the pot with a .001 cap. Out from pot through 470k bypassed with a 570p cap, on to second stage.

Second stage cathode - 2.7k bypassed by .68mfd (you'll notice this is the stock 1st stage values - you can save some time/trouble by just switching the wires on the first two stages).

Out from 2nd stage, through .022, into 1 meg pot (use one of the now extraneous input jack holes). Bypass pot with a .005. Out from pot through a 470k bypassed with a 500p, on to third stage.

Third stage cathode - 3.3k bypassed by a 330mfd.

Change tone circuit cap from 500p to 250p.

Everything else - leave as stock.

Notes -
-one could certainly argue that the 330mfd cathode caps could be smaller. This is probably true, but this value works well so I've never bothered to try.

-the two "gain" or "preamp" knobs should be set in the 5-6 range to hit the sweet spot. You could replace one with fixed resistors, but I have found that tweaking the two pots in the 5-6 range allows for a good tonal variation (due to the bypass caps) that helps when switching between different sounding guitars, etc., so I put them both on the front panel.

-Amps with EL34's or 6550's both sound very good. The 6550's sound "heavier".

-I believe this is very close to the mods performed by Frank Levi in the late 80's. I first started tinkering with amps at that time, and dissected amps done by Levi, Soldano, Lee Jackson, etc.... so, nothing original here!

Hope this is useful to you.

Click to expand...

Thanks MisterMiniMite, very interesting reading!

Cool stuff. Any chance you could tie all together and post somewhere on the net?? That would be cool to have all together as a reference. Thanks for your efforts into this.

we are talking extra 12ax7 to be this special "everyone wants to rent or steal" #39 or #36 amp. i'm recieving a 2204 head with extra 12ax7 tomorrow so i'm interested in exactly what was done to the 2 magic amps as i can always use some magic, lol.

OK...... I'm bringing up this old thread. But I've got some Questions.

The Silver Jubilees came out in '87. Slash was looking for a new amp in '87. Is it safe to assume Slash used the Jubilees for the tour with the cult, Aerosmith, and the AFD tour??


I've heard that he used a combination of the Jubilees and JCM 800s(2203) for the UYI albums......

Next, to AFD, I think his tone on The Speghetti Incident is his best..... what do you think he was using during that time??

Slash told in an interview with a guitar magazine, that the first time he recorded a song with his Jubilee/Signature amp was on VR's Contraband for the track "You got no right". So you can conclude that for The Spaghetti Incident Slash had to use a different amp.