Tube Socket Question

James Edward · November 20, 2010, 02:07:14 PM

I just received a couple of EAT 6922 tubes, with the integral tube damper/cooling fins. However, my amp has a post on either side of the socket, making it impossible to put the new tube in place. The width of the tube, when the damper is in place, is too wide to fit between these posts.
Are these posts removable? They appear to turn in place, but do not come out. I realize that without seeing the amp, it may be impossible to answer this question, but maybe someone has run into this before.

Thanks for any replies.

richidoo · November 20, 2010, 03:43:35 PM

What kind of amp is it?

James Edward · November 20, 2010, 05:25:29 PM

It is an integrated- LSA Signature

James Edward · November 20, 2010, 05:30:20 PM

Here is a picture- you can see the rings around each tube. Thoses were easily removed by unscrewing the nut at the top of the post. It is this post that I am wondering about removing. The posts will turn, but don't seem to be unscrewing. I should add that when they are turned and feel a little loose, the tube socket itself still appears firmly in place.
Thanks...

James Edward · November 20, 2010, 05:30:58 PM

The link I meant to provide:
http://www.positive-feedback.com/Issue35/lsa.htm

Response Audio · November 20, 2010, 06:09:50 PM

Hello James,
The rings should be removable by holding onto the standoffs below with a pair of plyers and removing the screws. I think what you are experiencing is that the screws underneath are spinning. I do not know for sure but i beleive they are similiar to those used in other products.

James Edward · November 20, 2010, 06:23:43 PM

I took the amp out of the shelf so I could get a closer look- and sure enough, there is a nut spinning below.
I can see it through the ventilation louvers in back. I put the amp on it's side figuring I would take the bottom cover off so I could access the nuts, but there is a second board underneath, so that's a no-go.

I will call Music Direct on Monday and special order the tubes without the damper/cooling fins.

And as Nervosa goes, I was perfectly happy with the sound of the EH tubes currently in place, but had to f%*& with it anyway...

tmazz · November 20, 2010, 06:53:57 PM

From what I can see in the pictures, it doesn't look like the ring comes in direct contact with the tube. I wonder that its purpose is. Anyone have any thoughts?

James Edward · November 20, 2010, 07:43:58 PM

FWIW, the rings are off, it's the post the rings sat on that are blocking the tube from seating. And I agree, I see no purpose for the rings anyway. They actually made it difficult to change tubes.

tmazz · November 20, 2010, 08:07:21 PM

Quote from: James Edward on November 20, 2010, 06:23:43 PM
I took the amp out of the shelf so I could get a closer look- and sure enough, there is a nut spinning below.
I can see it through the ventilation louvers in back. I put the amp on it's side figuring I would take the bottom cover off so I could access the nuts, but there is a second board underneath, so that's a no-go.

I will call Music Direct on Monday and special order the tubes without the damper/cooling fins.

And as Nervosa goes, I was perfectly happy with the sound of the EH tubes currently in place, but had to f%*& with it anyway...

You might be able to get enough friction on the nut to hold it in place by just pulling up on the post while twisting it. But before I did that I would look carfully and try to determine if there was a pathfor the nut to drop put of the amp if you urn it and shake it. The lat thing you would want is for it to fall onto that lower circuit board and short something. Before doing anything I would also turn off the amp and let it sit for half an hour or so to let all of the charge drain out of the power supply caps so that if the nut does fall across something there isn't a enough of a jolt in the caps to cause any damage. (Got quite a zap one working on an "unplugged" TV that hadn't drained down

)

tmazz · November 20, 2010, 08:11:35 PM

Quote from: James Edward on November 20, 2010, 07:43:58 PM
FWIW, the rings are off, it's the post the rings sat on that are blocking the tube from seating. And I agree, I see no purpose for the rings anyway. They actually made it difficult to change tubes.

Yeah, if the ring touched the tube It could be doing some dampining, but it's not. And with the cover on you don't see them, so it can't be for aesthetics. I'm stumped at to why they are there.

James Edward · November 20, 2010, 08:17:21 PM

"You might be able to get enough friction on the nut to hold it in place by just pulling up on the post while twisting it. But before I did that I would look carfully and try to determine if there was a pathfor the nut to drop put of the amp if you urn it and shake it. The lat thing you would want is for it to fall onto that lower circuit board and short something. Before doing anything I would also turn off the amp and let it sit for half an hour or so to let all of the charge drain out of the power supply caps so that if the nut does fall across something there isn't a enough of a jolt in the caps to cause any damage."

Exactly. There is no clear path for extracting the nuts, so I am going to just get the 'nude' version of the tubes.

tmazz · November 20, 2010, 08:40:02 PM

Quote from: James Edward on November 20, 2010, 08:17:21 PM
"You might be able to get enough friction on the nut to hold it in place by just pulling up on the post while twisting it. But before I did that I would look carfully and try to determine if there was a pathfor the nut to drop put of the amp if you urn it and shake it. The lat thing you would want is for it to fall onto that lower circuit board and short something. Before doing anything I would also turn off the amp and let it sit for half an hour or so to let all of the charge drain out of the power supply caps so that if the nut does fall across something there isn't a enough of a jolt in the caps to cause any damage."

Exactly. There is no clear path for extracting the nuts, so I am going to just get the 'nude' version of the tubes.

Good idea. You wouldn't want to get a high voltage short across your nuts.