2. amps-preamps
  3. 146907-18279

Really...My favorite power tube is reissue that's not widely popular

If you run 6l6/EL34 variants, I HIGHLY recommend trying this tube out.  The Tung Sol 7581A reissue.  I've had these for a good bit of time and compared them against KT150s, EL34s (several brands), KT88s, and maybe another that I'm forgetting.  They are a mere $30 a pop and they are the best tube I have heard. I know that's a brave bold statement to make as there is so much competition out there and the tube is very much under the radar from what I can tell.  

After having these around for a long time (and in and out of the amp), I had them in and was nearly spellbound one night by how great they sounded upon reentry into my amp.  I did a search and could only find one review, which I agree wholeheartedly with.  You can find it here: https://wallofsound.ca/audioreviews/amplification/6l6-vacuum-tube-review-tubes-courtesy-of-www-thetu...

I am nearly incredulous there isn't hype out there about this tube.  Simply my favorite tube.  I thought I'd pass this along as it may be much cheaper to give them a whirl then fuss with a much more expensive power cord, cable, or other tweak.  
128x128jbhiller

Showing 5 responses by salectric

salectric
747 posts
 
Metman, Can you share some details on your “Eico HF-20 JWN” amps?  Are these Eicos rebuilt by Jim Nichols using his input/driver circuitry?
salectric
747 posts
 
@metman 
 I suspect the amps I am using right now look and sound similar to yours.  I used HF-22 chassis (monoblocks), stripped them of all parts, and then rebuilt them using Jim Nichols’ circuit.  I kept the Eico output transformers (same as in HF-20) but everything else is new.  They sound great!  

Right now I am using RCA blackplate 6L6GC from the 1960s but I also have some SED Winged C output tubes that sound really good too.
salectric
747 posts
 
@noromance 
The stock Eico amplifiers are based on the Mullard 5-20 design.  It is a tried and true performer.  

The Jim Nichols circuit referred to above is a different design that uses a floating paraphase inverter instead of the Mullard long tailed pair inverter.  They are both capable of great sound.  So much depends on the execution.
salectric
747 posts
 
There are at least 3 Tung Sol reissue tubes that can be used in an amp designed for 6L6 outputs—the 7581a, 6L6G and 6L6GC-STR.  I recently bought two pairs of the STR version and have just started breaking them in.  So far I am very impressed.  They have a strong bass with excellent detail and weight, and the entire spectrum is fast and detailed.  I still prefer the midrange refinement and coherency of my vintage RCA blackplates, but the T-S is a bonafide contender.

I wonder how the other T-S reissues compare.  Have any of you with 7581a tubes compared them to either the 6L6G or 6L6GC-STR?
salectric
747 posts
 
@larryi 
I have never had 350B tubes to try, but I do have 4 sets of 6L6GC tubes that I have been trying in my new 6L6 amps.  These are RCA blackplates, GE gray plates, SED Winged C and new Tung Sol STR.  The RCA and GE are from the 1960s, the SED is from the late 1990s, and the T-S is a new reissue.  So far my favorite is the GE.



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