The 6550 Experience

[Billy Batz]

For so many years I just didn't have time to get into arguing about it, but I thought one day I might actually join a discussion to see what happens.........................
And no one is taking my word for it now either, I'm just a guy saying stuff.

Oh and Billy, thanks for jumping in again.

Adrien has kept in touch since Ive stopped posting here. He told me to get involved with this one since I was the crazy guy on here who believed in this nutso theory from some old article

People do get entrenched on forum debates.

[Xplorer]

Glad to see you here Dan !
Beaujolais ! great clips ! it's getting closer and closer ...
next months will be very exciting

Adrien

[Billy Batz]

I thought it fun to rehash and reread that old thread. I moved to the burbs this fall and have some space now so the other day I went to plug in the old 68 era switch monster with the same tungSol 6550s and BAM! Fuse. Must have a dead one. No spare fuses

[Xplorer]

that's a sign .... time to tweak it, and maybe experiment with the west coast mod

[frenchie]

You know, for the life of me I could never understand why folks had such a hard time believing there were 6550s in Jimi Hendrix' Marshall amps, at least those that were tuned up by West Coast Organ and Amp Service.
It always seemed so logical to me, especially when Marshall started shipping their amps with the same tubes.
The 6550 was more rugged, it lasted longer, and was a much safer bet for a traveling band which relied so heavily on the proper operation of their amps.
What do you suppose created all the resistance to this rather obvious fact?

Hmmm let me guess .... i'd say for 50% of the nay sayers it's business model related , 20% sheer stupidity with an inner crave for shameless trolling , the last 30% of them have at least a thousand posts raving about EL34 for bog and woodstock and must save the face because editing "en masse " leave traces ?

besides i have no doubt hastily "distributor" converted to 6550 plexis can sound bad , like anything that is not tuned up properly ... Now there are people eating a single bad apple who will dismiss apples as a whole .... I guess with 6550 it's the same ...
you will also see people buying high dollar gibsons online without trying them because they made some good ones in the sixties , and webstore sales of gibsons are HUGE....it's the herd behavior at play here ..Some people just have a hard time with novelty , you wonder how come they came to listen to hendrix ....

[daveweyer]

Tazin,
Why do you suppose Marshall started using those 6550s if they sounded so bad? Wouldn't someone at the factory go "hey wait a minute, this amp sound like shit with 6550s" and try to get the old sound back?
Do you suppose it was a corporate thing, to reduce warranty replacement costs or something?
Maybe they couldn't get good EL34s any more, or the price went way up.
Was there anything you had to do to the amps besides simply put the EL34s back in to get that sweet crunchy sound everyone loved?

[Tone seaker]

I had always heard Marshall changed tubes because during shipment from England to the US a lot of EL34's were not surviving the trip in new Marshall's

[bill bokey]

I was watching the Woodstock concert the other day and noticed the beginning of Spanish Castle Magic is played without the fuzz, we can see him reach for the pedal at the very first note of the solo. So I had a go, with the following amp settings :
Volume 7, Treble 4+, Mids 6, Bass 2+, Presence 9+

https://soundcloud.com/castle-made-of-s ... stle-magic


The speakers are definitely not the right ones for this job but I really enoyed playing it, there's so much gain, I didn't expect that with a Strat !

The fuuz is on 0 and the volume about halfway.

[stinkway]

I had always heard Marshall changed tubes because during shipment from England to the US a lot of EL34's were not surviving the trip in new Marshall's

Yup, same here. The switch wasn't for tone, it was for making the trip to the US. History being rewritten here on this forum lol

[Tone seaker]

When did Marshall switch tubes. What year?

[C J H]

No one in here has claimed that the switch was for tone either. If you read Dave´s post he clearly states that it was for increased reliability. so SAME REASON as marshall some years later (sorry Tone, I don´t know the exact year).

Anyway; Bokey, yes I hear alot of what you are getting but your amp seems to be gainier than mine (which makes sense). Nice playing and tone BTW. I´ll contribute when I get ahold on some mics and my Strat in order

Too bad some people can´t keep these discussions civil.. To all others, keep up the good work!

[bill bokey]

Anyway; Bokey, yes I hear alot of what you are getting but your amp seems to be gainier than mine (which makes sense). Nice playing and tone BTW. I´ll contribute when I get ahold on some mics and my Strat in order

Your amp has more NFB and no mixer cap IIRC. And has it a bright cap ? Mine has a 5nF, I'll try without eventually.

Anyway I don't know if the amp Hendrix used at Woodstock (or anywhere else for that matter) was ever setup like mine but I gotta say I really like it !

[Tazin]

Tazin,
Why do you suppose Marshall started using those 6550s if they sounded so bad? Wouldn't someone at the factory go "hey wait a minute, this amp sound like shit with 6550s" and try to get the old sound back?
Do you suppose it was a corporate thing, to reduce warranty replacement costs or something?
Maybe they couldn't get good EL34s any more, or the price went way up.
Was there anything you had to do to the amps besides simply put the EL34s back in to get that sweet crunchy sound everyone loved?

The mid '70s Marshall's are not really my area of expertise, but I kinda remember the story something like this:

Rose-Morris had distribution rights to Marshall products and I believe Rose-Morris used Unicord as their USA distributor. I guess Unicord was having problems with valve failures due to shipping; hence warranty claims; so around the end of 1973 they started using 6550 valves. I think what may have compounded the valve failures is the fact that tube production in the UK was declining and QC was following suit. It's a bit of a 'gray area' as to whether amps exported to the USA had output valves (6550) installed in them or not. I think it was either Steve Grindrod (Marshall) or Mitch Coby (Merson-Unicord) said they did not and Unicord was the one responsible for installing the valves and biasing them up....At least initially. All I do know is that Unicord had the facilities and capabilities to perform such actions. I believe Unicord went with GE 6550-A valves; verse other 6550 variants; and from what I gather tend not to exhibit a nice sonic palette like the EL34's so purchasers weren't always happy; hence the bad rap. Nonetheless, Marshall's exported to the USA had 6550 valves through to like the mid '80s.

Marshall amps shipped else where in the world during this time frame still used EL34 valves which I guess is what Jim Marshall preferred in his amplifiers.

[daveweyer]

Tazin thanks.
I can sympathize with Jim Marshall on the EL34 thing. It's hard to find a sweeter sounding tube. If I had a room full of Marshalls, I would definitely have one especially dedicated to to EL34 sound.
That said, for the more percussive and attack oriented sound, I would also have a 6550 amp.
I would hate to think it had to be one or the other.
I think the message that's coming out of this forum is that whatever tube you use, it has to be a decent one that excels at its job. And it does seem the earlier NOS American and British models had a lot happening in that regard.

[fakeox]

An old man memory here.. seems to me in the earlier 70s quality of the el34s took a nosedive & caused a lot of failures.