Did I save the blurriest photo for last? I sure might have!
This tube probably needs no introduction since it's popular here, but it's the GEC L63 with black ladder plates in clear straight glass brown base clothes.
Right off the bat what struck me about the L63 is how rich the tone is. It actually sounds quite a lot like a Marconi Osram B65 in terms of tonal balance, but it's a bit richer and bolder perhaps. That's actually kind of the theme of this tube all round I would say: rich and bold but without becoming too much or too heavy handed. It pulls it off without any overt bad habits either such as glare or honk in the mids or any etch or hardness in the treble. Pretty impressive.
I think the soundstage is what struck me most. It's intimate, and maybe the smallest out of all the tubes I've tested the past few weeks. Like my comment about the Brimars the sense of air and space just seems to feel more "dense" here, like it's more fog than air. This brings a strong ambience to some kinds of music. It's probably not actually smaller than the other tubes here but rather just comes across that way because the presentation is so musically 'dense' here.
Dynamically this tube is quite forward and expressive. Lots of energy but it's well controlled. I am particularly drawn to how it handles transients and leading edges. They are quick and incisive without feeling harsh or edgy. That's a hard balancing act to pull off. There's something about the presentation here that says "I'm powerful, bold" but at the same time it's still refined and controlled.
Did I save the best for last? Not quite. If I had to pick one tube out of this whole lot of nine it would be the Tung Sol VT94, and if I dropped one of them and broke it I would swap over to the Motorolas and not feel any immediate need to hunt down a replacement. I would put the L63s in a tie for second place with the Brimars. I think I like the Brimar presentation a little better overall, it has some of that round plate 3D holography going on with it's soundstage presentation and I think everything breathes a little better and layers a little better. The L63 is very good at layering and note seperation, it's just that all the musical information feels packed in so tight and I like the Brimar's presentation of that musical information a little better. What hurts the Brimar is that sometimes steely overtone in the mids, and I'm wondering if maybe more burn-in time would make it go away. But for now I think I'd just call it a draw between them. Both great tubes and great sounds.
To whoever is still reading thanks for tagging along and I hope these write-ups have been worth reading. Again this isn't meant to be used as buying advice per se. I didn't put enough effort into controlling conditions from tube to tube, it was more just a stream of consciousness thing. Hope somebody got something out of it though!
For a final wrap-up if I had to rank all of these tubes I think it would land like this:
1) Tung Sol VT94
2) Motorola (Tung-Sol) 6J5GT
3) [TIE] Brimar 6J5G and GEC L63
4) Raytheon 6J5G ladder plate
5) Raytheon 6J5G round plate
6) Sylvania 6J5GT black ladder late
7) Sylvania 6J5GT grey round plate
8) Sylvania 6J5G black round plate
The only tube in this entire list that I did not like was the Sylvania in last place. Which is super interesting because other people swear by this tube and consider it to be their absolute favorite. I guess it just goes to show that we all listen very differently and have different priorities when it comes to what we like. For me this tube just sounds inauthentic in a cartoonish way. Instruments just never sounded real. The only thing that really holds back the other Sylvanias, especially the ladder plate, was that they were simply outclassed by the tubes at the top of the list when it came to sheer resolution. The grey roundplate has it but it's a dead fish in terms of dynamics. The black ladder plate has the dynamics but it just doesn't have the low level detail and texture retrieval of the best tubes in the group. The Raytheons could also basically be another tie. I really liked the round plate soundstage presentation, but when it came to tone it wasn't as well balanced as the ladder plate whose overall presentation I thought was more even handed and pleasant.
One thing I will say is this: nearly every tube on this list is superior to the vast majority of the 6SN7s I have heard, and the top three on this list are flat out superior to EVERY 6SN7 I have ever heard and I have owned/heard pretty much all of the desirable ones over the years. There was consistently a sense of superior note separation and layering, but in the case of the Tung-Sols and the British duo they also had superior musical detail retrieval too. Other than a lack of new production offerings to ensure that future scarcity doesn't become an issue I'm quite surprised more amp makers don't use this tube over the 6SN7. Sure the circuit needs both triode sections sometimes, but in some amps it actually does not. Some even just leave one section unused and literally operate the 6SN7 as a 6J5. Maybe it's better, however, that this tube doesn't become as well known as the 6SN7 thought otherwise price and scarcity will quickly become an issue.