Anyone have experience with the Tung Sol 7581a vs. EL34, KT66, KT88, 6L6


I broke down and added another power tube (Tung Sol 7581a) to my collection.  That can get expensive as my Primaluna Dialogue HP Premium integrated has 8 power tubes.   

Why has this tube escaped me thus far?  Why is it not more popular?   Many folks don't sell this reissue tube.  

I think this is a great deal.  I was torn between the lush, thick midrange of the EL34 and the more evenly spread out sound of the KT88.  But the KT88, for all its more correct behavior didn't romance me like an EL34.  

The 7581a from Tung Sol can be had cheap and I really like them.  [I'll spare you all the audiophile terms].  They check the boxes that I was looking for. 

Does anyone have experience, information or knowledge about this splendid tube?  

PS  The next experiment is KT150s but I can't see doing it if I'm gonna lose any of that great EL34 midrange. 
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no romance - when I first tried the 7581As I thought they were good - but perhaps a bit "dry" and not as warm as the KT88s.  Mind you, I last used the 7581As some years ago.  They now sound quite fine - generally well rounded and "warm" .

I mentioned earlier that two of the KT88s I had been using failed in quick succession.  They were getting longer in tooth, and I suppose their sound quality may have gradually changed, i.e., degraded, a bit towards the end of their useful life, thus making any good, fresh replacement tubes sound better.

Who can say?  I do know I'm quite happy with the 7581As now, and I may buy another pair (or even a quad) to have for the next rainy day.

@rshak I found that too. Midband sweetness wasn’t there and they were a little tight. After 20 or so hours, they opened up. I’ve easily 1000 hours on these in my monos (2 tubes each) and they sound sublime.

I would highly recommend Philips ECG JAN 7581A circa late 70’s production … Unfortunately prices have escalated of late. 

Well, I guess one could say I'm sold on the Tung-Sol 7581A.  Bought a matched quad from Tube Depot, which arrived today in good order.  All in, the cost was $210.71.  Together with the low mileage set bought in 2017 and re-installed  a few weeks ago, plus the back-up pair from Viva, with any luck I should be set for the next few years.