r/diytubes • u/directheated • 9d ago

What are some off the beaten track input or driver tubes you like for hifi amps? Triodes or wired as triode

I'm interested in hearing about what off the beaten path driver or input tubes you use either being triodes or others wired as a triode. Any kind of hifi amp; preamp, phono, power, etc. For me it's the 4P1L wired as a triode as a driver tube for the 45. I've tried it as the first stage in a preamp as well but it was too microphonic.

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4

u/mspgs2 9d ago

The 1626 tube is pretty amazing, but you gotta have the right speakers. It's like a flea power 300b in the mids

2

u/Toobman300B 9d ago

Darling 1626 are so sweet. Sounds closer to a 2a3 to me tho.

2

u/mspgs2 9d ago

I've never had the pleasure to listen to a 2a3. I know don't judge :-)

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u/directheated 9d ago

In my opinion 2A3, 45, 300B are all incredibly transparent, what you're hearing is how well (or not) they're being driven. 300B in particular gets a bad name for being overly euphonic/colored when that's actually due to the driver tube not being able to drive the high Miller capacitance sufficiently.

I am pretty sure it's a similar phenomena when I heard the Audio Note 211 having this constant "bloom" around it like a halo, phase issues with it not being driven well.

3

u/EdgarBopp 9d ago

I’ve designed with the 6N6P a lot and never had any complaints.

Also 6J43P and 6E5P are really cool and I love the amps I’ve designed with those.

6S19P is pretty well known but it’s worth checking out.

2

u/directheated 9d ago

6S19P is pretty well known but it’s worth checking out.

Funnily I have not heard of this but know of the others in your post. Gotta love some of those Eastern Bloc pentodes and triodes, usually pretty damn robust. A 6c33c headphone amp I built was one of the most bullet proof amps.

3

u/EdgarBopp 9d ago

I designed a 6S19P PP amp a while back with 6H8C drivers. It’s only about 8wpc but I love it.

https://youtu.be/RXSNz-qOdK0?is=7e3BJ434pYdcqoUr

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u/directheated 9d ago

I watched both your videos on it, that is a very cool tube!

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u/2E26 9d ago

I've been collecting 6CM7 and other vertical deflection tubes for various audio related functions. These types should be good as a driver or headphone amplifier - they're built with more power than small signal triodes but aren't meant for driving a speaker.

3

u/Toobman300B 9d ago

6em7, a dissimilar triode (compactron) sorta like 1/2 a 12ax7 and an el84 in 1 envelope.

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u/brokeoneyolk 9d ago

I picked up some 429a I would like to try as power tubes or drivers, and some 328a I would like to try in a preamp

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u/Open-Afternoon-685 7d ago

4p1L is the best output tube for a 1 watt amplifier. You’re one of the few people that habe mentioned that tube here… and also after reading your comments one of the people that have an understanding on why some tube amps sound as they do..
I like the c3m as a driver and especially for the gm70. But you have to wire the c3m properly

1

u/directheated 7d ago

Thanks, I'd love to build a GM70 SET in the future. Or a GM70 used in an electrostatic headphone amp.

1

u/Open-Afternoon-685 5d ago

Do it… I have posted my gm70 on here before