2. amps-preamps
  3. 1245704137

Replacement EL34 Mullard valves for Leben CS300X

6+ months ago I succumbed to temptation and bought a used CS300X over the internet from a German dealer. The unit was in very good condition and the sound quality has been excellent. Sadly one of the Mullard EL34 output valves has now failed and a second is about to go. I have no idea how to source a replacement quad set - though I suspect scarcity is the least of my problems. Finding genuine NOS at a reasonable price feels like a very tricky business. Does anyone have any guidance?

PS - I have bought a quad set of Golden Dragons to keep me going. I suspect there is some run-in required but it does seem as though some of the original magic has gone.
richardjames
dopogue
1,773 posts
 
I replaced Xf1 Mullard EL34s in my SET monoblocks (where they're used as driver tubes) with the reissue Genalex/Gold Lion KT77s. Supposedly a drop-in replacement for EL34s, these KT77s have been absolutely amazing. Much clearer than the Mullards, which are supposedly the holy grail of EL34s. I have no idea how they'd sound in your amps but thought it was worth a mention. Dave
jwmazur
191 posts
 
Doesn't the CX300 use EL84's?
magnumpi205
504 posts
 
Genelex/GL KT77s or Tesla EL34L Blue.
Have been through them all and those 2 have been the best for sound and reliablity.
jrinkerptdnet
430 posts
 
agree with Jwmazur .. the 300X uses el84's
blindjim
3,092 posts
 
guitar amp thread
http://www.eurotubes.com/euro-j.htm

the tube store (canada )
http://thetubestore.com/el346ca7types.html

tube subing website
http://www.pacair.com/discus/messages/23/23.html

vaccumm tube world ??
http://www.vacuumtubes.com/6ca7.html

I'm not endorsing any of the above for purchassing or sourcing tubes from as I've no personal experience with most of them. I figured these links would help inform so some more intelligent choice could be made thereafter.

Only thing I'd also look into is the plate boltage or bias the maker of the amp intended for the tubes... although some are 'drop in exchanges, I'd prefer to know if I'm going to go another way... often minor voltage variances can and are acceptable.

I also agree with the mini remarks on the CED winged C the tube store posts.

if you need EL84... HAPPY GOOGLING!
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