X-101-C output tube spacing

[N8Nagel]

Could someone with an X-101-C please measure center-center spacing on the 7591 sockets?

This is related to the sad news that apparently Jim McShane is no longer going to be able to source Tung-Sol 7591s; I am trying to determine if I need to hurry up and order a quad or two before they're all gone. (I also have a HH Scott 340B on the bench with no outputs; I'll be measuring that one tonight.)

 

[Dave451]

Can't help you with the X-101-C spacing, but I just did get a back-ordered quad of Tung Sol reissues shipped today from AES. The rep there confirmed a supply shortage due to "production problems." I love the dang things (just put my newly-restored 340B in service with a quad of them). It's kind of like Costco--once you find something you really like, they quit carrying it. Looks like we're due for a run on the "tube bank" for these. Good luck!
Dave

 

[N8Nagel]

yeah I gotta measure the 340B as well to see if I can use EH. Am guessing no. Haven't actually received the X-101-C yet unfortunately, really bad timing for this to happen, and I'm too broke to justify buying extras so I better not toast 'em.

 

[bhamham]

7591 center-center spacing on a 500-b is 1-1/2" and EH's work. Can't imagine it would be different for a x-101-c but don't know. Another problem is they're too tall for cases.

 

[N8Nagel]

I don't have a case for the X-101-C so that's OK (for now, I don't have the funds to have one made anyway) According to Jim McShane (email I just got this afternoon) the current EH are 1.5" diameter, so that's got to be a press fit! (TS are 1.25")

I *do* have a case for the 340B and I just measured; looks like V4 is partially under the screen and partially under the wood, and the wood is exactly 3-3/8" above the deck of the chassis meaning it's REAL iffy if an EH would fit in that position (Jim says 3.25" tall, and I wasn't allowing for the protrusion of the tube sockets) Dammit. C-C on the outputs there is 2" so I could use EHs without the case, but it came with it and it's beautiful.

Part of me is tempted to shave some material from the case over V4 but I am assuming that would reduce the value of this unit to a purist?

 

[larryderouin]

Nate; In any FISHER I have that uses 7591's the EH's have about 3/16"to 1/4" (plus or minus 1 or 2 RCH(*)) of space between them. That's the 800C's and the X-101-B. Same with the Sansui 1000A. I prefer the Tung-Sols, but the EH's should fit, in the 101-C provided it followed FISHER's standard Octal tube spacing, with a little wiggle room. Scotts have a problem with the EH's and a Case due to placement and angle of the tubes. The X-101-C shouldn't have a problem with the case and EH's as long as the EH's are installed AFTER the case and removed BEFORE the case.

(*)(A RCH is a Red Short Hair which is slightly thicker(a micron or 2) than a Blonde or Brunette Short Hair.)

 

[N8Nagel]

LOL I've hung out with enough machinists you don't need to explain

So am I safe not buying the TS's for the Fisher? I really am pretty broke right now and really don't want to buy tubes until it's in my hot little hands and ready to play, but if it's a must-buy for the Tung-Sols I'll have to suck it up and do it so I don't end up with a pretty paperweight.

 

[audiodon]

This news makes me glad I have saved some vintage used 7591s for the units I have restored for family.
For any 7591 based Fisher integrated amp, you can either use EHs or the cabinet. Not both.

 

[gadget73]

The other more invasive option is changing those sockets out to make use of 7868 tubes. I did it on a Sherwood. Its a pain in the ass, no question, but at the time it was either find dwindling old stock or change the sockets. Can't fit an EH 7591 in a Sherwood, but the EH 7868 fits just fine.

 

[N8Nagel]

I did get a definitive-ish answer to the question, the seller of the X-101-C hadn't shipped it yet as of a couple days ago and he had a pair of EH 7591s laying around. Looks like as long as I don't try to put a case on it (and I don't have one) that should be OK