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July 27, 2021, 06:44:57 PM

Author Topic: S3X change?  (Read 107 times)

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Offline Mucker

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S3X change?
« on: July 20, 2021, 07:29:20 PM »
If I want to use a 6DN7 tube in an S3X, is it just rewiring of the tube sockets that is required? I am ready to pull the trigger on this amp but it looks like finding an inexpensive 6FJ7 replacement tube is getting harder. From reading, I understand there won't be much if any performance difference if doing so. Is that safe to assume? Thank you!

Greg

Offline Thermioniclife

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Re: S3X change?
« Reply #1 on: July 21, 2021, 03:21:48 AM »
The 6dn7 and 6fj7 are the same except for the package, 8pin vs compactron.
Lee R.

Offline Thermioniclife

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Re: S3X change?
« Reply #2 on: July 21, 2021, 03:43:54 AM »
It is quite doable, I did this and other changes to a pair of s3x amps. I insralled the octal sochets with the keyway pointing to the left.
YMMV
Lee R.

Offline Paul Birkeland

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Re: S3X change?
« Reply #3 on: July 21, 2021, 06:46:22 AM »
6FJ7s aren't widely available because we bought up all the ones that were advertised.  The supply will recover and you should be able to get replacement for under $10 each in a couple of years. 

These tubes last a long, long time.  I was getting 5 years of 24/7/365 use out of them when I ran an amp with 6FM7s without ever turning it off.
Paul "PB" Birkeland

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Offline mcandmar

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Re: S3X change?
« Reply #4 on: July 21, 2021, 06:49:08 AM »
lol

If you ask any of the larger tube sellers they may have some in stock, they fall into the "who the hell would want these" category and not worth the effort creating listings for.  I picked up many 6DN7's that way.
M.McCandless

Offline oguinn

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Re: S3X change?
« Reply #5 on: July 21, 2021, 07:41:59 AM »
I was buying 6FJ7s when I saw them come up (I think they're kinda cool in addition to using them in the S3X). I think I have a dozen or so if anyone needed a couple.
Jameson O’Guinn

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Offline Mucker

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Re: S3X change?
« Reply #6 on: July 21, 2021, 09:13:34 AM »
Wow, all kinds of great info, thank you all! Sounds like a very robust tube so should be good for quite a while.

I appreciate your thoughtfulness oguinn!

Cool amp Thermioniclife!

Sounds like it's time to take the plunge!