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
JJ KT77s are so inexpensive that I bought a pair a while back, and they sounded (surprisingly) so much worse in my Had SE amp that I simply shrugged and considered it a lesson learned. Maybe some amp synergy with the JJs was off, and I even tried different rectifier tubes to no avail...When I looked at Gold Lion KT77s and noted obvious build differences I finally got over my KT77 issues and was pleasantly surprised by how good they were, and kept them in the amp until the 7581As bumped them from the top spot.
Based on all your feedback I ended up getting a set of 4 for my PL Dialogue integrated and have about 25 hrs on them so far. I'll give some feedback once I get more time with them. To date I've used the original PL EL34s (still going strong) and KT150's. I love the huge sound and authority of the KT150's but use a pair of Mullards in the pre to warm things up and bring some texture to the mids. I still love the EL34s overall, though it's fun to swap back and forth and do so once a month whether it needs it or not :-) 

@arch2 and @tuberist What bias setting are you using for the 7581A's? Do you have it switched to KT88/120 or EL34? 
I’ve been bopping around through my systems this summer.  I just got back to horns fed by these tubes. Soooo good. Time has shown me these are just so special new production tubes. 
The review of 6L6s linked to further up in the thread lists the SED 'Winged C' 6L6 NOS as even better. Anyone heard those?