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

[bennyx]

this is DeMartini amp with Levi mod.....not 36...but have changed half components of pcb.....and i don't see bright cap....first and second stage are totally changed and in series like 2203 or cascade or onewired mod.....i see a shield trick

Good stuff Benny; I see some #36 clues in there...

This is what I meant by 'how Frank mods amps in the 80's'

Ok but he have heavy ripped the amp......Frank have remove totally first and second stage caps and res....remove a bright cap, put in series the stages, change treble peaker and add a cap on first mixer.....not exactly a minimal mod and De Martini sound isn't a tipical plexi sound and don't nail afd sound.....the DeMartini sound are very smooth, not compressed and with more mids......exactly the opposite of afd sound....if you want at home i've a Frank archive, i will you say that mod is in this head....Frank have make several mods, many mods are classic mods like one wired, metronix, cascade etc etc.....he don't have always invented mods.....

[pjoliver182]

He's made some modest changes...that's not what I meant by ripping it apart..

[bennyx]

He's made some modest changes...that's not what I meant by ripping it apart..

34 is a ripped amp? If make 34 with 10k added stage in a supertremolo head is a ripped amp?

[bennyx]

I seems to remember that also Metaltronix mod have an added preamp tubes....Frank have make some Metaltronix in his career....i've just see the is the page 666.....that's diabolic

[pjoliver182]

I'm proposing that the #34 mod required more changes to the stock circuit than #36 did...to end at a 'similar' gain/tone. And therefore that if you start your #36 clone with the #34 mod...you've made too many changes.

[bennyx]

I'm proposing that the #34 mod required more changes to the stock circuit than #36 did...to end at a 'similar' gain/tone. And therefore that if you start your #36 clone with the #34 mod...you've made too many changes.

Where is write that made too many changes? If 34 was made...Frank have make many change....add a 10k stage isn't a change on a supertremolo....

[pjoliver182]

#34 was made after #36. Though for a few years you had us believe it was the other way around. Nothing is written to say what the mod was of course...we can only use logical reasoning and the little evidence that exists. Also Frank seems to give good information to people who have no affiliation with amp businesses. To those who do, he seems to tell them what they want to hear...which I can respect.

[rockgod212]

a one wire wire mod variation does sound good with the right combination of components.

[pjoliver182]

Is slash using #34 on November Rain? Or was it the jubilee? The solos sound like a kazoo or something! Horrible buzz-like tone to my ear...

[bennyx]

#34 was made after #36. Though for a few years you had us believe it was the other way around. Nothing is written to say what the mod was of course...we can only use logical reasoning and the little evidence that exists. Also Frank seems to give good information to people who have no affiliation with amp businesses. To those who do, he seems to tell them what they want to hear...which I can respect.

The reasoning is: Frank have take 39 Caswell ( first version with 10k added stage that sound very bright), the amp was yet ripped, have remove switching and first stage mod....rest of amp was yet modded.....was 10k added stage yet.....probably 100n on second stage yet.....so Frank have make other adjustment and an old idea for sound that correctly for his ear.....that experiment call superkill....on second time he make 36 for clone exactly 39 superkill on demand to Glenn....on third time Glenn ask another amp with this voicing so Frank have only a 2203, he was make a 3 tubes version.....remove 10k stage so have create a low gain version......with same voicing.....

[pjoliver182]

Couple of things I disagree with there...

1) if frank did indeed rework 39...your own article says

"Frank removed all of the components that Tim Caswell had added on the 1st tube of #39 including the switching capability"

You've taken this to mean the first stage...but I think it's referring to the added stage and the 2k7 stock stage is on the second preamp tube...

This means the added stage definitely isn't 10k...which fits with the best sound clips I've heard on the forum....and also with what Frank himself told people (except you).

2) 34 HAS to be quite different to 36 and 39 to get a similar tone and gain with one less stage.

The 2n2 peaker, bright cap pi tail are how i think he tweaked it to get the right tone and gain. Remember too that a HUGE difference between 34 and the other two amps is how the phase inverter is used - the MV must be relatively cranked to get enough gain since there's one less gain stage...this will greatly affect the tone shaping.

Those are my main reasons for believing that 34 was not simply 36 without an added 10k stage.

[rockgod212]

a 34 style mod with a 5n brite cap does get very close to the AFD sound though........im starting to like my 34 set up like that. its got the bite and gain just less bass'y sounding. very crunchy when cranked up. I also like my 34 with no peaker plus 150k on gain with a 5n brite cap, crank it and it sounds great.

[pjoliver182]

a 34 style mod with a 5n brite cap does get very close to the AFD sound though........im starting to like my 34 set up like that. its got the bite and gain just less bass'y sounding. very crunchy when cranked up. I also like my 34 with no peaker plus 150k on gain with a 5n brite cap, crank it and it sounds great.

You're right mate, but there are tons of variations of the mod that get close. The first two stages set most of the tone and we know what they are. The added stage, bright cap values and inter-stage attenuation / treble peaking circuits are mostly what set the mods apart.

I also don't think 36 had 6550s for what it's worth.

[bennyx]

Couple of things I disagree with there...

1) if frank did indeed rework 39...your own article says

"Frank removed all of the components that Tim Caswell had added on the 1st tube of #39 including the switching capability"

You've taken this to mean the first stage...but I think it's referring to the added stage and the 2k7 stock stage is on the second preamp tube...

This means the added stage definitely isn't 10k...which fits with the best sound clips I've heard on the forum....and also with what Frank himself told people (except you).

2) 34 HAS to be quite different to 36 and 39 to get a similar tone and gain with one less stage.

The 2n2 peaker, bright cap pi tail are how i think he tweaked it to get the right tone and gain. Remember too that a HUGE difference between 34 and the other two amps is how the phase inverter is used - the MV must be relatively cranked to get enough gain since there's one less gain stage...this will greatly affect the tone shaping.

Those are my main reasons for believing that 34 was not simply 36 without an added 10k stage.

On a supertremolo 2k7/680n are on first tube not on second tube......

[novosibir]

Looks like a beast; which of your amps it that one?

It's a beast with 6 EL34 power tubes, but it's not an amp of my amp line, but a rebuilt Marshall 2203 with the circuit of the DINO 939 in it.