Jimi Hendrix' Gear and Mods at West Coast Organ and Amp

[Doug H]

Awesome thread

Going back a bit, Running the 6550s at ~550 and the screens at 530, I'm guessing the 2.2k screen grids didn't knock that much off, how did you get the voltage down?

I'm a bit confused about the various power sections you mentioned and all the fuss with different phase inverter tubes and such just so cold biased 6550s wouldn't melt at 550 volts? I guess it's a different world on the road. I'm gonna go back and read that stuff over again, it sounded like there was more detail coming and then the conversation changed, maybe I missed a couple things.

Thanks for all the great info

[frenchie]

this is the maximum i could get.

http://i.imgur.com/2A29Xh6.jpg

you can also compare the diameter of the voltage selector, which is about 3 cm.
so the tubes , compared to this, look about 4 cm large. so in the ball park of what you said.

strange thing is that the maximum height of the tube ( mirrored upper glass ) in your cleaned pic ( 2nd superlead ) is lower than the upper end of the bulge on the output transformer which isn't the case in my cleaned pic ( 1st superlead ) ... were there mismatched brands of 6550 between the two super leads ? at first it seems the first superlead has clear glass big bottle 6550 and the second superlead has mirrored upper glass tubes .....

anyone have a theory on that ?

[yladrd61]

Yeah I've still got the tube modulator and it works well. I just took the pictures the other night.
I'm working on getting you a chance to hear it.

Interesting about the long green resistors, I often used those in amp mods or repairs. I never used 7027s in Marshalls, but I did in Fenders. Sweet sounding tube. Better look for a West Coast sticker on your amp!

Haven't seen Frenchie's video, is it positive evidence or negative evidence?

Second try on this post.

My 1970 Super Lead is S/N SL/A 5132A, I still have those green resistors they have "10F1500 WARD LEONARD" and they have green dye on the solder connections. This amp has a very high B+ 509VDC, 504V on the screens with NOS Mullard EL34s, and 1K 5 Watt screen resistors so they must have put the 1500 Ohm screen resistors in there to limit the screen Voltage. So you used 2.2K, to do the same thing on Jimis Amps with the 6550s ? My amp is also shared cathode with no bright cap and both channels internally jumpered, with a Pre PI MV (1 Meg Pot from Treble Ctr wiper to .022 coupling cap)

[Tone seaker]

[swankmotee]

Frenchie, different sockets have different heights too where the tube may sit higher or lower and they do get replaced a lot due to voltage arching between pins when a tube blows.

[swankmotee]

Hey Tone, please don't go there because everything Dave has described in electronic terms makes exact, factual sense and some of thats flies over some posters heads because they don't know the theory. If any of that had been incorrect or misinformation I would have cried foul long ago. Everyone's input is valid here just as long as they are willing to "learn" and remain open minded! Nothing Dave has said has been a personal slam on anyone here and it's only been informative, well written, and backed up with enough factual evidence that I have 100% faith that he did the work he said he did. Please stay involved and just remember to be humble and respectful of what this gentleman has to offer.

[stinkway]

A lot of guys, me included have done an awful lot of research on Jimi for the good part of 45 years. Read interviews with him, people involved with him, etc.
The original GP article, IMO was (even then) fishy at best. The fret filing and such. No proof. IMO, bs. This guy is claiming he worked on a few Jimi amps. Fine. Why, in the original GP article wasn't the (claimed) extensiveness of all the mods noted? Why weren't the fuzzes mentioned?
Claims there was some junker Guild amp onstage. Where? Where is it? Now claims to have tape of Jimi playing thru one of his inventions, but conveniently can't dig thru 1000 tapes.
Claims if Jimi played thru his toy he wouldn't have needed a Univibe. Jimi started using a Univibe months after he worked on those few amps. There was no further involvement. Transformer switching, 6550's, etc. No proof. Jimi's fuzzes had the fuzz set at zero when they arrived at his shop, so that's how he ran them? I doubt it. Any schoolboy knows what a Fuzz sounds like w/ the fuzz dimed and that's what we all hear.
What's unfortunate, is the amount of little guppies, buying this guy's bs stories, hook, line and sinker. You are fools who have been duped.
Like the other dude said, after 45 years guys like Billy Cox have memory loss but he don't?

You've all been had

[daveweyer]

Tone seaker,
Yes, please stay involved and keep posting. I, for one, very much value your input, and your presence on the forum is a very positive thing for all those who are working on the story.
Your input is NOT meaningless!
All of us who had some direct involvement with Jimi are working from memory, and those memories are getting kind of old. That's one reason it's hard to reconcile them all, I like to see photographic proof as much as anyone.
My suggestions were just that, possibilities toward resolving discrepancies, not taking sides.
My apologies if I came across as doubting your word.

[Tazin]

I hear ya Tone seaker....It is fustrating when you believe something to be true and you find yourself trying to defend that truth. I try to keep an open mind about things and be as objective as possible specially when it comes to second and third handle knowledge. Like I mentioned before, sometimes the way I phase things tend to make them sound confrontational, but believe me that is not my objective. About the pictures....Hindsight tells me I should have never even mentioned them since I am in a postion where I cannot share them. So that was a mistake on my behalf.
The '60s was a long time ago and even I don't remember a lot of what I did back then with 100% certainty. Shit, I don't even remember if my house was white with red trim, white with blue trim, or blue with white trim back in 1969....But the car was a late model 1964 Chevy Impala; that I'm certain about.

[Tone seaker]

ok thanks guys. Ill hang in there and keep putting any thing I come up with. Thks

[frenchie]

Frenchie, different sockets have different heights too where the tube may sit higher or lower and they do get replaced a lot due to voltage arching between pins when a tube blows.

makes sense swankmotee ...

For all i know your just some one trying to prove the theory about 6550's and its still not proven. You cant claim it of hearsay by you or pics from a distance of the back of a amp with the cover on it

okay ... this need a repost ;

http://www.partage-facile.com/PEJYGV06C ... s.pdf.html

have a good read now .... if you want , come back at me later when your LOGIC is fully loaded and ready to kill ....

[shakti]

Classic stuff, frenchie!

Still waiting for my 6550s though...

[Tone seaker]

Frenchie, different sockets have different heights too where the tube may sit higher or lower and they do get replaced a lot due to voltage arching between pins when a tube blows.

makes sense swankmotee ...

For all i know your just some one trying to prove the theory about 6550's and its still not proven. You cant claim it of hearsay by you or pics from a distance of the back of a amp with the cover on it

okay ... this need a repost ;

http://www.partage-facile.com/PEJYGV06C ... s.pdf.html

have a good read now .... if you want , come back at me later when your LOGIC is fully loaded and ready to kill ....

Classic stuff, frenchie!

Still waiting for my 6550s though...

Still waiting also. Your LOGIC is just to hammer me and that thing you posted I got tired of trying to watch it after 5 different adds and it still had not loaded. Attitudes like yours keep people from having any opinon different than yours here and ruins discussions.

[mathd]

Please, i think we should try to make this place as much friendly as we can.

I mean, sometime maby its best to send a PM instead to make that in public or take a few minute or day before posting..
Honestly i dont give a shit what the little "chest beating fights" are about, but the less the better.
Am not trying to point someone, this is a message to the general public of this forum.
Dont want to offend anyone there, if i did.. simply send me a Pm(if your language is decent you will get a reply).

Please... Peace....
And dont forget, hendrix will be happy if someone get a different sound while "experimenting new ways..".
Hey hendrix sounds good.. but sometime i think we could try new ways"like the davophone" and do better or just different?
Thats what "the experience" is about.


So... lets get started and try out new things, any idea?

[Doug H]

I finnaly went thru all 10 or so adds and its the planet of the apes movie. WTF does that have to do with Woodstock

lol