Philips 7581A

[FourT6and2]

Who knows anything about these tubes? How do they compare to new production Tung-Sol 7581A? Compared to regular 6L6GC?

 

[Exo-metal]

Mil spec equivalent to the 6L6

 

[Anje]

From memory the old Philips /Jan / Sylvania 7851A were a beefier military spec version of the 6L6 GC; great tubes.
Never directly compared them to modern versions so can’t comment on that sorry.

 

[CDawg]

30 vs 35 watts plate dissipation. Similar sound from the same company but more headroom and longer lifespan.

GE is the most articulate across the board but especially in the midrange, emphasizes attack and is very neutral sounding. Philips is a little more articulate than Tung Sol but not as articulate as GE, has great sustain and adds to the lower treble region. Tung Sol emphasizes the attack and is neutral but not as articulate as the others.

Tung Sol 7581A is one of the only modern tubes I use. It's nice to go buy a new matched set at a reasonable cost. Currently have Tung Sol in a Rectifier and Philips in a Mark III and 5150.

 

[Racerxrated]

From memory the old Philips /Jan / Sylvania 7851A were a beefier military spec version of the 6L6 GC; great tubes.
Never directly compared them to modern versions so can’t comment on that sorry.

THIS 1000%.

I also think the Phillips has a 35w rating compared to 30w for the Sylvania 6L6GC. But, like we've talked about before in a vintage amp they will shine more vs any new prod tubes...in a modern amp, well, you'll have to try and see. That result varies a bit.

The only newer amp I've bought that appreciated vintage tubes was my newly built Naylor SD60. My Mesa Triple has been hit/miss. It does love the 90s Sovtek 5881 wafer bottoms.

 

[psychodave]

I have like four quads of them. They are great. New production cant touch them.

 

[ilikehats]

I have them in my Twin. They are fantastic, sound huge.

 

[FourT6and2]

There's a guy selling a few quads on Reverb. But he wants too much for them ($800/quad) and he has no way of testing them. He also wants $50 for shipping, which is utterly stupid. There's a slightly used quad on eBay for $380 that test at 89% on a TV-7, which is also stupid because that doesn't tell you if they're a matched set or what the actual plate current draw is. But it is what it is...

I'll probably just stick with modern JJ 6L6GC at this point. Unless anybody has a quad they're willing to sell and/or trade for some of the NOS tubes I have?

This would be for one of my Granophyers. They sound great as is, but I guess the NOS tube bug has me curious.

 

[FourT6and2]

View attachment 465421

30 vs 35 watts plate dissipation. Similar sound from the same company but more headroom and longer lifespan.

GE is the most articulate across the board but especially in the midrange, emphasizes attack and is very neutral sounding. Philips is a little more articulate than Tung Sol but not as articulate as GE, has great sustain and adds to the lower treble region. Tung Sol emphasizes the attack and is neutral but not as articulate as the others.

Tung Sol 7581A is one of the only modern tubes I use. It's nice to go buy a new matched set at a reasonable cost. Currently have Tung Sol in a Rectifier and Philips in a Mark III and 5150.

Interested in letting a quad go? I might trade and/or buy.