- Western Electric (JW, D-Getter, Etc.)
- GE 5 Star Red Triple Mica
- GE 5 Star White Triple Mica
- GE Triple Mica (non 5 star, but sounds the same)
- Tung-Sol JTL-2C51
- RCA Command 5670
- Westinghouse 5670
- Sylvania JHS 2C51
- Motorola 5670 (internally identical to the CBS tubes--must have been made by CBS Industrial)
- Raytheon JAN 5670
- CBS JHY-2C51
- Sylvania Gold Brand
- CBS Industrial
- Sylvania JAN
- Raytheon CK5670
- Tung-Sol Halo
- GE JAN 5670
I would love to go about ranking them in great detail, but it's a project that is probably beyond the time I can commit. All I'm truly after myself are "what's my favorite" and "what's the best all-rounder that I can get for a reasonable price?"
My favorites are probably the Western Electrics (D getter--I can't hear a difference between the JW and non-JW). But for a slightly punchier bass and a little more air in the treble, any of the GE triple micas are awesome and are much cheaper than the WEs.
I have also tried out the Bendix 6385. If you need a little more detail and brightness in your life, these are pretty impressive. I'm too treble sensitive for them. Another good option for the same purpose are the Sylvania Gold Brand, which are also considerably cheaper than the Bendix. Halfway between the two in price and availability would be the CBS Industrial. Hard to find but quite good with gobs of detail.
I've not yet heard Tesla 6CC42 or new production JJ 6386 tubes. I probably won't anytime soon, as I'm focusing on availability and bang-for-the-buck.
I'm using these tubes in the MHDT Labs Atlantis DAC and that is going into Garage1217 Project Horizon, Sunrise, and Ember amplifiers. Being able to tune sound with tubes both in the dac and amp is awesome.
Tung-Sol 2C51 1958 D-Getter is rather good. Right up there with the big guns.
Smooth, authoritative, and detailed. It's not quite as full sounding as a Western Electric, which could be a good thing depending on your amp.
What I've largely found is that the rankings MHDT has are pretty accurate. They don't account for flavor, but you could probably plot out a spectrum of what each tube type delivers.
Bendix seems like it's the winner for detail, Western Electric for maximum enveloping tube sound, then there are quite a few somewhere in between.
Tung-Sol 2C51 is almost as smooth as the WE but has bigger (albeit looser) bass delivery and a little less lush sound.
GE Triple Mica isn't as smooth as the WE but has impactful (again looser) bass delivery and a bit more air (nowhere near Bendix).
Sylvania Gold Pin is airy with big bass punch and fairly bright highs (perhaps more treble even than Bendix).
CBS Industrial is pretty similar to the GE Triple Mica but with a little tighter bass (it belongs in the 2nd Class list) and a little less lushness.
RCA Command to my ears is warm like a Western Electric note for note but slightly less excellent overall (and available for less money).
Raytheon CK5670 is a very good all-around tube. Doesn't do anything wrong, but doesn't knock my socks off.
6N2P-EV (with adapter) combines excellent soundstage with powerful bass and slightly pushed-down treble.
Everything else I've tried is at least a tier below and isn't really bad, but you can find the above tubes for a great price if you look hard enough.