At that budget price point, I like the Tungsram E88CC and the National / Matsushita 6922.

But National is usually Matsushita, i.e. Japanese. I thought at first that was the Svetlana logo, but I don't think it is. That's a weird one.

Seriously? Wow

Do you also use EQ? I get so frustrated trying to reconcile EQ and tubes.

Spanish wine in the morning? That's a way to start a Sunday!

Was getting some clipping using heavy EQ with HE6SE V1 and Tungsram tubes, so put the LISST tubes in to test. After a couple hours of warm up, the LISST are sounding fine.

I just got a pair of HE6SE V1 (power hungry) and EQ'd them pretty aggressively using Oratory's curve (making them even more power hungry). On high gain, with all the PEQ bands turned on, the Tungsram tubes I had in at the time were clipping a bit (who can blame them). So I swapped in the LISST...

Oh they're going to kick you out of the club for that! New production better than NOS? uh oh ;)

Interesting. Do you know who makes the S4A for BTB? Because it's almost certainly a rebranded JJ, Russian, or Shuguang tube. The 2nd & 3rd harmonics on the graph similar to what I've seen from my EH 6922s.

Interesting...I've got a pair of those, too. They might not be my quietest, but they're not one of my noisier tubes.

I'm surprised 2nd is lower than 3rd and 5th. Curious what tubes you were using?

HAR! BTW, where did the graph come from?

But there are two brown lines. And one of them is flatlining.... ;)

When you guys talk about the brown line, are you talking about the noise floor line?

Steady state fundamental level of interest?

Lowering distortion, and noise, is the main goal of feedback, yes. On the flip side, it may diminish audibility of differences between tubes.

The line about planars was in reference to the Audezes mentioned. But the 33 ohms of the Kennertons are lower than I'm shopping for. I'm looking specifically for high impedance closed back phones.

Do you need to use a 12Ax7 adapter to use them in place of a 6922, or are they direct drop in replacements?

Thanks, but I already have low impedance cans (HE6SE, HE400i) to use with my MJ2 (see sig). I'm not looking to get more planars right now. But I'll definitely look at the ZMFs.

I've never even heard of them. Do they have any models that are >100 ohm? All the models I'm looking at on their website within budget are 33 ohms.

If I'm shopping for a closed-backed, high impedance headphone to use with an OTL tube amp (Schiit Valhalla) is the 1770 Pro still on the short list? What others should I also be looking at that are <$1000?

I can find references that the MJ1 had a zero feedback design, but I'm not clear if that was dropped in the MJ2. Also, Jason seemed to imply it changes between high and low gain.

Very interesting. Were all 5965's meant for digital use, or just some of them?

I have to wonder at the look of disappointment that a porch pirate gets when opening a package of stolen loot and is faced with the mysterious object of a socket saver.

Oh I thought the 6CG7 was not advised for the Valhalla 2 because it uses 600 mA heater current, which is out of spec for the amp.