jimi hendrix superlead questions

[Xplorer]

Hi ,

as i'm thinking of rebuilding my metroamp 69 to vintage specs and parts ( keeping the metro board aside untouched )
i started to compare the classic layout, and the pictures of the jimi hendrix superlead. on both ( one is only a possible hendrix amp ) , i don't see this main filter cap ! where is it ? and are there any other variations you may notice ? i'm quite interested.
also, if you saw this amp on a concert picture, i'd love to know more :

http://amparchives.com/album/Marshall/1 ... lead2.html" onclick="window.open(this.href);return false;

thanks

[Roe]

sorry, but I don't understand what you're asking about. pics show a standard 69 chassis with caps on top. are you referring to the dickinson amp with the caps on the boards inside the chassis?

[Xplorer]

Thanks Roe,
in fact i'm not comparing the dickinson jtm but a superlead and a possible superlead, very close, with a 68 layout. i don't see the 32+32 uf cap in there. and i'm curious about the other mods and components types that may be seen in there.

[Roe]

the preamp filter cap is on top of the chassis (like a 69)

[Xplorer]

shame on me lol... and i have a 69 clone !! ha ha. long time since i didn't look inside ...
anything else anyone may notice ?
these 10uf caps seem very big ... ( but this may be me, i have only the jtm45/100 in my mind since months and months now )
i also see some unusual type of caps here and there : so can we conclude that this one was modded from the first time jimi had it or something ? or why changing some mustard caps for some others like some wima ?
i see a ceramic cap accross the volume 1 pot.
about the size : are these 10k iskra 1w or 2w ? the 1w i have seem to be that big so .. i'm wondering.
some pihers and CC here and there ... quite stock in fact ! isn't it ?

[yngwie308]

Here are my 1959HW pics, post George's upgrades, this is the 1969 circuit, hope this may help..
http://s57.photobucket.com/albums/g219/ ... %201959HW/" onclick="window.open(this.href);return false;
yngwie308

[Xplorer]

thanks, beautiful build.

And i finaly ound that on the original superleads, it was some 1w iskras for the 10k and 8k2.

[Tazin]

A couple of things here that might help clarify stuff. First, the second picture posted (called Possible Hendrix 2.jpg) is not a Hendrix amp, rather it's Super Lead SL/A 10836. This amp/picture was just used to show a clearer image of what the Hendrix amp ( SL/12361) was originally like before the modifications, but somehow it got tangled up in this mess and tagged as something tied to Hendrix.

Secondly, even though amp SL/12361 was originally a split cathode style circuit Hendrix had it changed to a shared cathode style. So now both halves of the first preamp tube use the 320uF/820ohm setup.

Lastly, Marshall amps of this time frame (early 1969) used WIMA caps frequently. So, it's not uncommon to see WIMA caps used for the values of 0.022uF and the 0.68uF combined with the Phillips/Mullard caps for the 0.0022uF and 0.1uF. The output coupling caps on the Hendrix amp were changed to the RS brand 0.022uF for some reason despite the fact that the original WIMA caps were the same value (0.022uF). The rest of the modifications appear to be just "fine tuning" of the amp to Jimi's liking. This would include the changing of the Bright channel coupling cap, and the changing of the cathode bypass cap on V2a. And yes, the amp still retains the RS 0.005uF Brite cap on the Volume pot.

[Xplorer]

very nice explanations on things i couldn't see myself. thanks ! how do you know all that ?
do you know some other things on this hendrix amp ?
yes i thought that the picture "possible henrix amp" wasn't hiw amp. i think i saw one other amp from this period that looked almost the same, on amparchives.

[Tazin]

very nice explanations on things i couldn't see myself. thanks ! how do you know all that ?
do you know some other things on this hendrix amp ?
yes i thought that the picture "possible henrix amp" wasn't hiw amp. i think i saw one other amp from this period that looked almost the same, on amparchives.

Let's just say that I've been in a few dicussions about the amp through the years.

[Cheech]

I have been wondering about this amp too. I just noticed the shared cathode right now. I am not sure if I am understanding straight but to me the resistors look like carbon fiber. Your saying that one or more resistors were converted to carbon comp?

[Tazin]

I have been wondering about this amp too. I just noticed the shared cathode right now. I am not sure if I am understanding straight but to me the resistors look like carbon fiber. Your saying that one or more resistors were converted to carbon comp?

This reputed Hendrix amp has only six carbon composition resistors and the rest are carbon film. The carbon comp (CC) resistors are in the following positions: the three 820 ohm cathode resistors for V1 and V2a, the two 470K mixing resistors, and the 27K bias resistor.

[yngwie308]

thanks, beautiful build.

And i finaly ound that on the original superleads, it was some 1w iskras for the 10k and 8k2.

You're welcome though my amp was built at Marshall...
yngwie308

[Xplorer]

Hello !
it's been a while for this post, i'm resurecting it a bit since i'm currently modding and correcting a bit this metro 69.

id like to see it with some hendrix values in it.

compared this schematic, i'm assuming that Jimi's superlead had :

- no difference with this schem except for a 5000 pf on the vol pot,
- changing of the Bright channel coupling cap, and the changing of the cathode bypass cap on V2a

actualy, what values would it be ? and where are they located ? the cathode bypass cap on v2 is one of these 0.68uf , right ?

- six carbon composition resistors and the rest are carbon film. The carbon comp (CC) resistors are in the following positions: the three 820 ohm cathode resistors for V1 and V2a, the two 470K mixing resistors, and the 27K bias resistor.
- shared cathode


currently, my amp features a shared/split cathode switch, and i corrected some silver mica caps, ( big mistakes i made when i built my first amp ! the basse and mediums didn't even work lol ) .
it features two SRC 500 pf, one lemco 50pf, and i tested an RS 5600 pf on the vol pot but i think i prefered without it, with some better cleans i'd say. the gain earned seamed not so hendrixy.

is that all ? thanks !