Hello,
Find out that this works fine even in a combo amp.
Look at the drawing ( its in excel ).
sincerely,
Henk
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Quiet operation for a EF86 Penthode
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HBamp
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HBamp
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Hello Gabi,
It's 2 x 1,5 mm and I use hard rubber for it. It's glued together with
the same glue you use for repairing bycicle tyres. The holes are punched out with the same handpunch I use for the tube sockets.
I made a double template to drill the litle holes for the screws an the guiding hole for the handpunch.
Henk
It's 2 x 1,5 mm and I use hard rubber for it. It's glued together with
the same glue you use for repairing bycicle tyres. The holes are punched out with the same handpunch I use for the tube sockets.
I made a double template to drill the litle holes for the screws an the guiding hole for the handpunch.
Henk
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Gabi
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dboul
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Hi guys,
I've experimented with very very complex shock mounting schemes and I've found out that it's really about the tubes. Certain brands are much more solid than others.
Second, it's important that you let the tube get hot for a long time the first time you fire it up. Don't turn it on and off often when you first use it. A lot of EF86 microphonics is caused by the spacers cooling off and shrinking. After they've shrunk, there's no hope. They will rattle. So make sure you burn the tube in gently and slowly before you run a lot of signal in to it.
Lastly, the most effective thing we've found at 65 is to use neoprene rubber washers on the tube socket to reduce vibration, we use 3 on the bottom and 2 on the top.
Also really helps to orient the tube horizontally instead of vertically. The regular 18watt chassis puts the tube about 2 inches from the back of the speaker. The concussion from the speaker just beats the hell out of the tube. Our chassis has the tubes horizontal like a JTM45 and that REALLY helped with the EF86.
But really, it's still about the tubes. Dr Z uses a standard tube socket, not shock mounted. Same with Matchless. They just have to do what we do . . . buy 100 at a time and weed them out.
Strangely enough, I've noticed that Mullard's and Amperex's are really cool high gain tubes, but about a 60% reject rate, especially in a combo.
Okay so here's the good news . . . very good news actually.
JJ is making EF86's and I'm supposed to get some samples this summer.
At NAMM we at 65 went to Jan Jurco himself (JJ) and begged him to make EF86's because we heard from his crew that he was considering it. I got an email from Jan a couple of weeks ago confirming that they have tooled up and will have initial samples for us to check out soon!
I'll definitely keep you updated and I'll have to buy a couple of hundred to get "the deal". We'll happily sell some to all of our 18watt.com bretheren!
Stay tuned for progress!
Cheers guys!
I've experimented with very very complex shock mounting schemes and I've found out that it's really about the tubes. Certain brands are much more solid than others.
Second, it's important that you let the tube get hot for a long time the first time you fire it up. Don't turn it on and off often when you first use it. A lot of EF86 microphonics is caused by the spacers cooling off and shrinking. After they've shrunk, there's no hope. They will rattle. So make sure you burn the tube in gently and slowly before you run a lot of signal in to it.
Lastly, the most effective thing we've found at 65 is to use neoprene rubber washers on the tube socket to reduce vibration, we use 3 on the bottom and 2 on the top.
Also really helps to orient the tube horizontally instead of vertically. The regular 18watt chassis puts the tube about 2 inches from the back of the speaker. The concussion from the speaker just beats the hell out of the tube. Our chassis has the tubes horizontal like a JTM45 and that REALLY helped with the EF86.
But really, it's still about the tubes. Dr Z uses a standard tube socket, not shock mounted. Same with Matchless. They just have to do what we do . . . buy 100 at a time and weed them out.
Strangely enough, I've noticed that Mullard's and Amperex's are really cool high gain tubes, but about a 60% reject rate, especially in a combo.
Okay so here's the good news . . . very good news actually.
JJ is making EF86's and I'm supposed to get some samples this summer.
At NAMM we at 65 went to Jan Jurco himself (JJ) and begged him to make EF86's because we heard from his crew that he was considering it. I got an email from Jan a couple of weeks ago confirming that they have tooled up and will have initial samples for us to check out soon!
I'll definitely keep you updated and I'll have to buy a couple of hundred to get "the deal". We'll happily sell some to all of our 18watt.com bretheren!
Stay tuned for progress!
Cheers guys!
0 x
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HBamp
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HBamp
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- Joined: Fri 06/18/04 2:00 am
- Location: URMOND The Netherlands
- Contact:
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Gabi
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