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
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.
glow_worm
84 posts
 
Working around the Eico sidebar....good question re midrange. Let’s face it we are all looking for the “Goldilocks” tube, the mid warmth and tone of the EL34 and the highs and lows of the KTs. Have the 7581a’s now, trying to find time to plug them in. 
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?
wolf_garcia
6,672 posts
 
My Dennis Had "Inspire Fire Bottle HO" single ended amp (12wpc supposedly) will accommodate everything from KT150s, 120s, 88s, 77s to 6l6s and their ilk, and, other than 6L6s, I've tried all of the above. Swapping out the rectifier tube can help things, but I generally keep a 274B in there...before the 7581As the Gold Lion KT77s sounded best by far, and I raved about them like an unhinged maniac. Now I'm so impressed by the 7581A's tone palette and seemingly effortless tight power grip from top to bottom, they're staying put. Besides, the blue phosphorescence is so appealing, and clearly I need to get out more.
willmacc's avatar
willmacc
80 posts
 
Keep these comparisons coming.. interesting to read above subjective opinion on 7581a and GL KT77. Also quite curious why some prefer the JJ KT77 over the GL version. Thinking the JJ KT77 may be similar in some ways to the 7581a.
More to discover