Modded JCM 800 AFD/Slash amp demos

[gldtp99]

http://www.soundclick.com/bands/default.cfm?bandID=741589

I've been messing around with Marshall JCM 800 mods for the past while and did up five different Slash/AFD modded amps----most scratch built, one real Marshall, and one converted Laney AOR 50---- three 50 watters (two with EL34's one with 6L6GC) a 25 watter with JJ 6V6S and a 14 watter with EL84's.
My friends James and Bobby came over and took them into the studio across the hall from my workshop and this is what they came up with---- the three clips with "AFD" in the title...............gldtp99

[EL34]

Not sure what I am supposed to do when I click on that link?

Do you have a link to the song?

[gldtp99]

In the center of the page there is a list of songs--- all amp demos in this case---- to the left of the titles there is a "play" icon (a triangle or arrow)----- click the play icon to start their player, it opens in another small window.
I don't know how to link directly to their player----maybe someone can help here..............gldtp99

[EL34]

Is it the Mule 25 JCM800 link?

[gldtp99]

No, not the Mule 25 link--- that's an older stock-type JCM 800 build with JJ 6V6's and Heyboer 18 watt iron that i bought from you.
The new clips all feature "AFD" in the title, they're also the first three in the list--- referring to the album "Appetite for Destruction" by Guns and Roses--- this first album was a big seller and featured a modded Marshall sound that many are going after again, including the Marshall factory themselves (the new HI-$$$ limited edition "AFD 100" Slash tribute amp).
The orig modded amps in question were modded by Tim Caswell and Frank Levi.
My amps are experiments see just what kind of lead channel i'd like to build into channel switching (clean/dirty) amps-----rock players around here seem to like the tone/dyanmics of these modded amps very much----somewhat similar to a stock JCM 800 with a good OD pedal but with more gain, sustain, hi mids/hi response. All the orig amps modded by Caswell/Levi were 100 watt Marshalls running 6550's----none of mine are 100 watters----- three are 50 watters (two with EL34's and one with 6L6GC's), one is the same 25 watter (JJ 6V6's) as in the old clip but modded to a version of these specs and another is a 14 watter running cathode biased EL84's.
Only one of my amps was built by Marshall, a 4010 50 watt JCM 800 1x12 combo---another was orig a Laney AOR 50 (new turret board--- still using orig Laney iron), the other three are scratch builds (the 14, 25, and the 6L6GC 50 watter).
Some amps are using three preamp tubes, as a stock JCM 800, and some have an extra tube added--- the #34 Mod uses the orig three preamp tubes but the #39 and #36 amps use four pre tubes.
I brought over two of my talented guitar playing friends, rented some studio time, and these three "AFD" clips is what they came up with---- Bobby did two individual amp demo clips and James brought over a backing track (drums, bass) and did a song-like clip with Left/Right/Middle rhythm tracks and another lead track--- Bobby also did a short lead track on this clip---- the 14 watt amp was used for the lead guitars on this track, James used a wha-wha pedal on his lead and Bobby used a Tube Screamer on his.................gldtp99

[LooseChange]

Cool sounding stuff. But I'm confused... Did you mod the amps to be JCM800 preamps? You also mentioned that you added a pedal in front of the amps when these were recorded.
Tell me more about the specific mods. I just finished a JCM800 preamp and I am curious as to how yours differ, if they do. Thanks!

[gldtp99]

The amps are all JCM 800-type preamps that have been modded to higher gain specs, different types/versions of the online Slash/AFD mods out there---plus some have my own ideas in them--- different wattages/output tube types--- five amps with different approaches as an experiment to see what works best as a Lead channel in yet-to-be-built channel switching amps--- i brought over two friends and let them loose in the studio with these amps (they'd never played them before) and the three new clips are what came out of it.
The leads in the two individual amp clips do use a tubescreamer (Bobby wanted to use one) but it doesn't add much gain--- these have plenty of gain by themselves--- Bobby is the only player, out of many that have played these amps, who wanted to use any additional boost-----we were in the recording studio and he felt more comfortable with the Tubescreamer so that's what we went with---- he uses a Tubescreamer in front of his Marshall Jubilee when he plays live so that's what he likes.
In the other many-tracked demo, the lead isn't boosted----- both James and Bobby used a Wha-wha into the 14 watt head for their leads----- no amps (three different amps in this clip) are boosted in this clip--- that's what they sound like in person.
Another player and his son came over and demo'd these amps last night---- Van Halen freaks---- they never felt any need for more boost ---- but i did hook up a Chorus pedal for their VH riffs/leads--- they used it sometimes.
James (author/main player of many-tracked clip) wants a lo-watt channel switcher with the lead channel tone similar to the 14 watter that was used on the lead tracks of his clip---- i have a Bogen SE 10 watter (SE 7868--- i'll use a 6L6GC) coming from ebay that i'll pull the iron from and build him the channel switcher---- or i could do another push/pull EL84 output section--- or i could do push/pull ECL86 outputs as i have two cases of NOS Tungsram ECL86's sitting here---not sure yet.
First i have to build a 6L6GCx2 push/pull (35-40 watts) version of a BF Princeton Reverb--- single 12" speaker--- for another guy----James is working up a Rockabilly demo for this amp to be recorded @ Christmas break----all in my almost non-existant spare time.........................gldtp99

[gldtp99]

As to the specific mods to the stock JCM 800 preamp----- most of the info is contained in this 111 page thread at the Metro forum: http://forum.metroamp.com/viewtopic.php?f=3&t=29759.
There are layouts of many different builds of different versions of the three basic Slash/AFD mod amps: #34, #36, and #39---- these numbers orig identified the stock # stenciled to the ends of the rental amps owned by SIR studios, they owned and had their in-house techs (Tim Caswell and Frank Levi) mod some rental stock Marshall amps back in the 80's.
Over at the Metro forum there has been this on-going project to re-create the tone of these modded amps--- i've used what they've provided and added my own changes on some of my five experimental amps as i've seen fit.
The #36 and #39 Mods have an extra preamp tube----- the #34 Mod does not----- there are detailed layouts of several versions of #36 and #39 mods---- there is no detailed schematic/layout of #34 Mod because they say Frank Levi (tech who did this mod--- Slash still owns the orig amp and it was used as a base by Marshall for their AFD 100 amp) wishes that this detailed info of the #34 Mod be kept "secret" (even though there is enough info out there to figure it out).
None of my 5 experimental amps matches any schematic/layout exactly --- mostly because all the orig amps were 100 watters and none of mine are---i've also used several different approaches on my amps to see how local players react to them, trying to get useful input (as in:What one(s) do you like best? and why?) from players who demo my amps- i tend to like whatever one i'm playing at the moment the best so input from many different players is valuable to me---so far i've gotten a lot of "they all ROCK !!"---- which is great for my ego but doesn't offer much info from an amp builder's point of view.
You, or anyone else, are very welcome to stop by my workshop to play and give opinions of these amps--- i'd welcome the input !!!--- and i'd be better able answer questions on how each amp is modded...........................gldtp99