My "new" '71 Marshall Super Lead

[Carbia]

Hi guys!

I'm very happy 'cause I get a '71 Marshall on eBay yesterday for a good price

The amp looks great, but we'll see when I got it at home.
It has Drake transformers instead of Dagnalls and most of the amp looks original.

Some pics:












According to what I seen on the photos the 330uF/820ohm on the first tube isn't original, and the 2k7 resistor of V1B too.
Then, some screen resistors and the power and standby switches.
The rest looks original. Am I right?

[Carbia]

Any opinion?

[neikeel]

Well, it is a Rosemary, something was done to the PT loom but it still looks original.

The rest looks good, odd partial bypass of V1b cathode (previous MV cascade?)

A few connections to tweak and realign back to stock (unless the mod blows you away?)

I think we need clips to really comment

Mine like this was hugely loud and you really had to wrestle with it - definitely need hairs on your chest to manage one of these!

[Carbia]

Well, it is a Rosemary, something was done to the PT loom but it still looks original.

I don't understand that phrase
Can you explain it to me?


when I got it, I'm going to fix the messy wiring and fix the preamp's cathodes, and I hope it will roar!

And you'll get clips, of course!

[Tazin]

Rosemary was one of the assemblers at the Marshall factory....You can see her name in the Back Panel slot on the paper tag adhered to the chassis. The Rosemary reference is kinda like the Abigail Ybarra thing regarding Fender pickups. A lot of people have some killer sounding Marshall amps that just happen to have her name on it so she became somewhat elevated in status. Neil's statement about the PT loom has nothing to do with the Rosemary reference....It's just the way he structured the sentence.

[Carbia]

Ahhh, thank you!

The loom part I guess that means that the PT wiring route was changed at a certain point, sure?

[appetite4distortion]

Those big-ass Drake transformers from the early 70s are da bomb - I have one, my only metal panel, and despite I have access to many plexi amps, I really cannot part from it, no matter how hard I try.
These DO sounds different from Dagnalls amps IME.

[Carbia]

Yes, sounds different.

To me, they roll off a little treble and the power transformer sags more than Dagnalls of the same years.

I have mine in 240v tap and it has 475v on the plates, that goes to 415 at full volume. On the screens it goes to 385v

If I set it on 220v's tap I get 515v on the plates... but I don't trust modern tubes to handle it...

That's the result of having 230v on the plug.

[Carbia]

I arranged a little bit the board and the wiring.

I put a NOS resistor/capacitor in V1, fix the wiring and put a .68uF cap across V2a cathode. I don't have any .68 Mullard so I had to use a Mallory.

Well, and I installed a Lar/Mar to allow me to use the amp



Better, right?

[awangotango]

let us know how this compares to your friedman 3 stage amp.
i recently built a '67 clone with those newer white mallories and sounds great. I'm not sure I could tell much difference from the mustards except the mustards might be a touch darker.

those blue 10uf bias caps look original no? if your bias drifts you may want to swap them out.

all the other filtering looks original, which is good. try and keep them if possible. has the amp seen regular use? if so, they are likely fine.

i would cut the screen filtering in half by using only one side of each can..unless you want the stiffer metal panel filter specs. same with PI and preamp filters. lower filters might work better with drakes, will give the amp more breath and 'pump'

the case looks superb condition.
those two 560pf mixer and tone caps are key to getting original tone. nice to see those. should be a nice amp.


if you feel the need to jump channels like in the pic. try friedmans' tweek = solder another 560pf on the second mixer and then blend the two channels by ear using the volume controls (no jumper). this really fattens up the tone without mud and but lets you control the blend same as when using the jumper cable, I've had great success with this. only difference is mine uses vol bright cap which helps keep things cutting. I don't quite see one on yours, and recall the friedman didn't have one either...



what's the B+ from that PT. I had a '71 firebreather with 550V. loved it

[Carbia]

let us know how this compares to your friedman 3 stage amp.
i recently built a '67 clone with those newer white mallories and sounds great. I'm not sure I could tell much difference from the mustards except the mustards might be a touch darker.

The Friedman is more focused, gainier and "polite". This is raw, organic... beast.
The white Mallories runs very well. I've tested in some builds and they are nice

those blue 10uf bias caps look original no? if your bias drifts you may want to swap them out.

Yeah, the bias caps are original Hunts. I watched the bias current on the scope and there's no ripple and the bias stay adjusted.

all the other filtering looks original, which is good. try and keep them if possible. has the amp seen regular use? if so, they are likely fine.

Yeah, they are originals and the amp has no noticeable noise, so they would be fine. Anyway, I'll reform the caps using Larry's technique to promote life.

i would cut the screen filtering in half by using only one side of each can..unless you want the stiffer metal panel filter specs. same with PI and preamp filters. lower filters might work better with drakes, will give the amp more breath and 'pump'

I like the stiffness to play rhythm a la AC/DC. I can try, but I'm afraid of ghosting... The amp has a little bit ghosting full dimed, and I guess that if I reduce the filtering, I'll have more. Now doesn't bother me, it's too little, but if goes more...

the case looks superb condition.
those two 560pf mixer and tone caps are key to getting original tone. nice to see those. should be a nice amp.

The case is in very nice condition for 44 years old. And those RS caps are great.


if you feel the need to jump channels like in the pic. try friedmans' tweek = solder another 560pf on the second mixer and then blend the two channels by ear using the volume controls (no jumper). this really fattens up the tone without mud and but lets you control the blend same as when using the jumper cable, I've had great success with this. only difference is mine uses vol bright cap which helps keep things cutting. I don't quite see one on yours, and recall the friedman didn't have one either...

I only jump the channels to use the strat. With Gibsons the bright runs well alone, buy maybe I'll try what you say.



what's the B+ from that PT. I had a '71 firebreather with 550V. loved it

Well, you know that here in Spain we have 230v on the plug. So, if I use the 220v tap I have almost 520v and If I use the 240v tap I get 475v.

I don't trust modern tubes to handle 520v so I have it in the 240v tap running 475v on the plates.

Thank for comment

[awangotango]

sounds like a sweet amp, and in good hands. I'd be interested to hear more about the difference you hear and preference for 2 or 3 gain stages. Also, it sounds like the stock PT wants to put out about 525v running at 220? Which sounds about right for that year and almost as much as the one I had. That year ran higher B+ from what I understand. But yes, with modern tubes, you don't want to go over 500 for sure. I used mullards at 550 and the sound was sublime. I variac'd it down to 100-110 (B+ probalbly came down close to 500). Stupidly sold my '71 SL though. Big mistake! That amp was instant eddie tone!

[Carbia]

Ok, let me explain about the '71 and the 3 stage.

3 stage sound is more "perfect". Sounds pretty similar to BE100 demo videos. Very defined gain,balanced tone and great with any guitar at any volume.

The '71 is raw, is uncontrolled, but more authentic, more like old AC/DC.

3 stage is friendlier, very easy to play, but maybe too much "polite". '71 is a beast.

I recorded a clip with a friend two days ago, I'll post as soon as I get it

[awangotango]

yep raw is a good way to describe a two stager. regarding the 3stage, think I know what you mean by polite. It is hard to describe in words but easy to hear in reality! like alot of tone, it's all in the room at the time. After that so much happens to the signal it's hard to discuss
3 stagers can clean up but like you say they are still somehow more organized and focused a sound (polite) for some reason while the 2 stage is just more nonlinear. Maybe that 3rd stage can be seen as just another 'shaping' stage that forms the sound, that the 2 stagers doesn't benefit/suffer from. Looking forward to a sample when you get tme......

[Carbia]

What I tried to describe as "polite" is that the amp sounds like in a record, you know, like a mastered recording.
Maybe too pretty for my wild ears