S.I.R. 100W SuperLead Schematic pt. II

[BRMSlash]

Thanks. I've got partial bypasses on the 2nd and 3rd stages. Since I moved the 2nd stage from the 1st to the 2nd tube, the sound hasn't been able to clean up as much, so I upped the partial bypass resistors. This does clean it up a bit, but I think it loses too much gain and boost. Hence, in my last clip I lowered the resistors back to previous. The cleans still need a bit of work, so I think I may need to lower the B+ going to the 1st tube slightly and maybe adjust the 1st stage output resistor to ground.

I haven't tried the SE Lead mod, but I have used it for some ideas.

[snakepit86]

are you using all 100k plate resistors?

try with lowering the resistors that goes to ground in the voltage divider, like 470k/220k and if it doesnt work try with 1M/220k (the 1m resistor tames also some highs and noise), specialy if its the 3 stage and you go with a cathode resistor lower than 10k (the lower the resistor the gainier the sound and also gets a little thin) try to partially bypass with 2k7 and use 4u7 cap

i've been testing some big caps around 2 and 3 stages, i liked a very little cap on 2º and a big one on 3º to fatten up a little the sound, if it goes too flubby use partial bypass and change the couppling cap.

sound seems to get a little SPECIAL around 47n/470/4u7/47uf, magic numbers perhabs? mmm

[BRMSlash]

Yeah, still using the 100k plates.

Which voltage divider are you referring to? Either way I don't they'd help in this situation. I've currently got a 150k/150k on the input to the 2nd stage, although I was previously using a 150k/330k. My 3rd stage output voltage divider adds up to 600k and I won't be changing that any time soon, as it effects the feel of the amp.

I've tried big caps before with some success, but I don't think they help with clarity, even after adjusting the coupling caps and/or using a little cathode cap on previous or later stages.

[Prowler]

Here's a longer clip (full of mistakes ). I lowered my partial bypasses slightly and put back the cathode follower.
http://sclk.co/s7wdkz

Sounds great BRMSlash! What kind of reverb plugin or pedal are you using on this clip?

[BRMSlash]

Cheers. Using Reaper's built in ReaVerb with Reverb Generator and Filter(LP/HP).

Wet: -6.5
Dry: +0.0
Start Pos: 40ms
Length: 750ms
Volume: 0.0dB
Room Size: 80
Dampening: 65
Stereo Width: 1.00

Low Pass: 10400
High Pass: 0

[stoof]

as i promised, the AFD double mono izzys guitar!

http://www.filedropper.com/1987-appetit ... emono-izzy

i must say what i discovered at 15, they are 2 different worlds izzy and slash sides buy togheter they created the best hard rock album ever

Thanks a lot dude

[snakepit86]

you are welcome stoofy!

[bennyx]

re fresh solder.....one shield trick....tone stack stock......2n2 second treble peaker

https://www.youtube.com/watch?v=E-apfXn48kY

[BRMSlash]

There are some nice tones in there Benny. What speakers are you using?

[bennyx]

always g12-80 celestion.....cabinet 1982 jcm 800

[maxamus]

always g12-80 celestion.....cabinet 1982 jcm 800

Found this info on other thread seems there's more chance they used G12 65s than the 80s, are you sure Slash used the 80s?.


Although your probably more interested in the modern designs, it doesn't hurt to know the extended history of Marshall 4x12 cabs, because this legacy impacts the modern designs and designations, as well.

Terms like JCM800, JCM900, ...ect... just denote the time period that the cab was built and do not denote modifications in design. A lot of Marshall's confusing numerology stems from their old distributer; Rose-Morris. Jim Marshall had to make a deal with RM in 1965 to obtian a larger factory. A lot of the numbers like 1960, 1982, 1987, ect.. were simply the stock numbers that RM listed in their catalogs. In the year 1980, the RM deal expired, but RM held considerable Marshall JMP invetory to saturate the retail market with for some time. Marshall came up with a new look for their products, and a new name to make the RM invetory obsolete in the market. The new name was JCM800. 800 simply denoted the decade of the 80's with an extra zero added.

The original Marshall cab was slant faced (simply a cosmetic thing) and open backed. It had acoustical foam lining the inside too. These cabs were loaded with Celestion G12 Alnico 15's. By about 1964 it became completely closed back but retained the foam lining for a few years, but this was eventually dropped, because many players didn't like it, and ripped it out thinking it deadened the resonance. After the full stack became a big thing, a straight front version was offered. The early straight front, or B cabs , were about 4 inches taller. The slant, or A cabs, were stacked atop the straight cabs.

Post 1968 to JCM 800 cabs are pretty simple. It was the same cab, but the cab numbered 1982 was loaded with G12H30's, and the 1960 was loaded with G12M25's. In 1978 the G12-65 replaced the Greenback. The G12H30 was replaced by a G12-50, then eventually by the G12H80 (aka Classic Lead 80). At that time the G12-65 was well recieved, because it exuded the same warmth of the Greenback (with a tite bass), but the 80's were not liked much at first. The 1982 320 watt cabs were considered too tight, and too bright, and too agresssive. The 80 watt loaded cabs soon made a following among lead metal players though.

In the mid 80's the new speakers now had so much power handling that there was no point in offering a heavy duty cab, and the 1982 was dropped. The G12-65 was superceded by first the G12M70, and then by the G12T75, by about 1985. The G12M70 was much hated as perhaps the most sterile sounding Celestion ever. The G12T75 wasn't much of an improvement, but it was an improvement. It had the tighter bass of the 65 but had scooped mids in comparison. I still find the 75 harsh and brittle, and so did many others at the time. The Vintage 30 came into it about 1987 as a ceramic alternative to an alnico 15, and Marshall was quick to have their own version of this to quell the complants about the more modern speakers. This became the 1960 Vintage cab.

The steroe switching and jacks came into use with the higher power handling JCM 900 era cabs. The standard cabs used the G12-75's and the Vintage used the V30. After a awhile you could get the regular 1960 cab with re-issue Greenback, called the 1960 Classic. This cab doesn't have the steroe jack plate. There was also the reissue cabs with 60's (1960TV) and 70's (1960X) cosmectics. Both of these are Greenback loaded. The 1960TV was 4 inches taller like old straight fron cabs from 66 and 67, but it's a slant front to be used with the JTM45 re-issue heads in a 1/2 stack format.

All these top line cabs are 13 plye birch, except that the post 72 cabs have particle board back plates.

[bennyx]

Jcm800 1982 most common speakers in this cab was g12-100 and g12-80....g12-75 on mid 80's cabs.....g12-70 and g12-65 was more common on combos version....g12-70 and 65 don't sound right don't have right mids and right trebs......

[maxamus]

Benny where did you get your info on Slashs cab?

[bennyx]

Benny where did you get your info on Slashs cab?

Don't exist exactly infos on afd cab.....Slash on first period was use jcm 800 cabs on several live stages......on pre afd period he was use Risson amp with greenbacks cabinet (not Marshall cab), sometimes was used 2210, other times a 2203, other times a 1959 ( i have see it in a photo, seems to me #39.....so, he was said on his bio "i was a 2203 stock (that he was used for clean sound) but i was wanted a more distorted sound" so probably he was used his jcm 800 cabinet with 36....so i have try all jcm800 speakers......the only that have right mids and right treb are g12-80....

[BRMSlash]

Some good info there. In regards to G12-65, I own both current model G12-65 and Classic Lead 80's. As far as recording goes, the CL80's are the only choice as they give more clarity, punch and headroom. The CL80's are quite punchy and beamy, whereas the G12-65's have a better spread of sound but lack definition and punch for recording. In summary, for playing I prefer the G12-65 due to the better spread of sound, but for recording the CL80 is my speaker of choice.

It's interesting, that I hear quite a difference between the G12-80 and a CL80. The G12-80 seems to have more of that greenback type tone. Or it may just be the cabinet differences that I'm hearing?

I'm planning to get some Scumback H75-PVC's in the new year, as listening to the clips on their website, that speaker seems to have the tonal qualities I'm looking for. I'll probably get the 65w versions as I don't fancy setting the paper voice coil formers on fire in the 25w version.