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

[pjoliver182]

Benny on a 1959T the tremolo circuit is on the first preamp tube...

[pjoliver182]

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.

Cool! Is there anything of the original amp left? Just the transformers sockets and chassis? 6 el34s...jesus!

[bennyx]

Benny on a 1959T the tremolo circuit is on the first preamp tube...

Sorry you have right but usually Caswell move first stage on first tube (2k7/680n) and change value of second and third stage that are the old first and second stage.....so switching system are behind 2k7 stage and second stage.....i don't believe that Frank have re-move 2k7 on second tube

[pjoliver182]

Caswell keeps the stock 2k7 where it is and works to the left. Your own photo also shows that.

[bennyx]

Caswell keeps the stock 2k7 where it is and works to the left. Your own photo also shows that.

That pics have new Caswell switching system.....an old black/white pic show the old minimal switching system more simple and without switching pcb make on a normal 1959 have a first stage preamp tubes added with 2k7/680n.....input cable was in first stage added....the first stage on original pcb was totally changed with 3k3 330uf.......so Caswell on time have changed the way to make 39 and have added more voicing and gain possibility, that have create a dedicate pcb very sofisticated to install directly on the amp without change original pcb values but have several cable to connect all parts of amp.....simply changes wires connections....but first 39 don't have this system and have only 2 or 3 possibility to change gain and voicing....and he have use only 1 or 2 mechanical switch have less cables.....new switching system have electric commutators.....supertremolo sir was the old system.....very easy to remove....but i'm pretty sure that Caswell have use a tremolo tube for make the real first stage of amp....he haven't add tremolo tube behind other stages....that's more complicated to move value of old first stage on new tube

[BRMSlash]

Here's my latest clip. I've ended up with a 470p snubber on the 1st stage and none on the 4th. Grid stoppers are 39k, 220k, 220k, 150k from 1st to 4th stage. I also haven't been using any 10k cathode stages for a little while now.

http://sclk.co/s7w47w

[pjoliver182]

I see what you're saying Benny. Do you have any of those old photos? You say there was a 3k3/330u stage instead of the 10k/0.22u? Interesting...

Tim spoke about his mod here on the forum years ago but unfortunately he has since deleted all his posts...

[pjoliver182]

Here's my latest clip. I've ended up with a 470p snubber on the 1st stage and none on the 4th. Grid stoppers are 39k, 220k, 220k, 150k from 1st to 4th stage. I also haven't been using any 10k cathode stages for a little while now.

http://sclk.co/s7w47w

You have grid stoppers on every stage? How come?

[novosibir]

First of all - sorry guys for off-topic.
It wasn't my intention, to enter this thread for profiling myself and I'll be quite here again soon. Promised!

Cool! Is there anything of the original amp left? Just the transformers sockets and chassis? 6 el34s...jesus!

No even the transformers & the choke are DINO. Original left the chassis, the panels, Power & Standby switches and some elements on the right area of the back panel.

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[bennyx]

I see what you're saying Benny. Do you have any of those old photos? You say there was a 3k3/330u stage instead of the 10k/0.22u? Interesting...

Tim spoke about his mod here on the forum years ago but unfortunately he has since deleted all his posts...

The first 39 mod make for Sir , was a too bright amp, Caswell have admitted that, Frank confirm that.....Frank was ask to Glenn to re mod for make a better sound.....for me Frank don't have complitely remove all mod....he have simply re work on mod for sound better....so probably have used some component of Caswell mod, other have remove.....39 was born like an experiment.....Frank wasn't come back the amp stock....have remove the part that he don't interested, let the parts he was interested and put new components for complete a new mod

[pjoliver182]

I can see why it was too bright yes. To make it less bright you'd just remove/reduce bright caps and treble peakers...

[rockgod212]

yes all of that would do it, plus increasing full freq. gain on xtra stage to add some low end to balance out the tone and give it that squish.

I can see why it was too bright yes. To make it less bright you'd just remove/reduce bright caps and treble peakers...

[bennyx]

I can see why it was too bright yes. To make it less bright you'd just remove/reduce bright caps and treble peakers...

Or remove bright cap and increase treble peaker....like Frank style

[pjoliver182]

Depends what the extra stage of the original 39 was though...10k...or....

[dukeamps]

http://soundclick.com/share.cfm?id=13256062