Yikes.

Nope, not yet! Just got them this evening and working the next three days, so probably later this week. I have another pair of Ken-Rads, different base but same internals if memory serves, they're good tubes.

Girlfriend found these for me at a flea market, NIB and $10 a pop, not too shabby! She likes to go antiquing, every time we go I try to find tubes and fail. The one time I didn't tag along, she found these. There were maybe 4-5 Ken-Rad 6SN7s in the box too in various states of condition, but...

With a higher Vdrop rectifier, the peak power output will be slightly less, but that is power that no headphone will ever use. So no, there is no downside.

5R4 types will work with anything. No you don't need to stick with GZ34 or GZ32 for higher power stuff, you can use other rectifiers. Just need to be mindful of using GZ34 or GZ32 with certain low power output tubes.

I need a GVM (glossal voltmeter) rated up to 600V, might save me a few bucks on batteries for my DMM. Can this man help me?

Yeah looks that way.

Oh thanks! Unfortunately those aren't going to work, will bias beyond max ratings.

Just bought a pair of Tung-Sol 6K6GT to test. Should work but want to confirm with real world numbers. EL81 I cannot find any triode data. Plate dissipation is 8W and screen dissipation is 4.5W, could work but I can't say for sure. If someone really wants to use this tube, they can send me a...

Here's a pair of Hytron 6F6G (suspect they are made by RCA). These bias too hot with a GZ34, work great with a 5R4. Another one that would be best with higher Vdrop rectifiers, like 5U4, 5R4, 5Y3. Same for KT63.

The two halves don't have to be closely matched, anything ballpark is fine.

Yup. GZ34 / 5AR4 is the lowest voltage drop to rectifier made, so pretty much anything else will get the EL33 further away from its maximum plate dissipation.

Who's on holiday? I'm slaving away over here!...:smirk:

Next up, the Mullard EL33. Another nice pair, good condition. Same envelope as the EL37. Okay so in terms of biasing, these bias really nicely in this circuit. With a GZ34, they are right near their maximum ratings, not quite there, but close. So you could technically run them with a...

6550 and a production Aegis have landed. These tubes are pristine, this was a good buy. Up and running on the top rack. Oh, these 6550s are nice. Perhaps a little less airy and spacious than the EL37, but still throw a large stage. Definitely more meat on the bone, and great tone...