Tubes for AKG C28 etc - size does matter!

Hi!

I wanted to audition some 6072 / 12AY7 tubes in my AKG C28a, and was surprised to find that some brands are simply too wide or too long to fit. The modern EH 6072a is both wider and longer!

Obviously I don't want to spend money on tubes that don't fit. Has anyone else found this and noted tubes brands that do / don't fit?

BTW, I asked this over on the mic forum at prosoundweb, and got the answer... 'get an original GE five star', which is fine. (But maybe I'll look for an AC701, a VF14 and the holy grail whilst I'm at it....).

Like most of us here I enjoy experimenting with different components. I'd hoped for some more creative suggestions - I should have posted here in the first place!

Cheers!
Stewart

[quote author="zebra50"]Hi!

I wanted to audition some 6072 / 12AY7 tubes in my AKG C28a, and was surprised to find that some brands are simply too wide or too long to fit. The modern EH 6072a is both wider and longer!

Obviously I don't want to spend money on tubes that don't fit. Has anyone else found this and noted tubes brands that do / don't fit?

BTW, I asked this over on the mic forum at prosoundweb, and got the answer... 'get an original GE five star', which is fine. (But maybe I'll look for an AC701, a VF14 and the holy grail whilst I'm at it....).

Like most of us here I enjoy experimenting with different components. I'd hoped for some more creative suggestions - I should have posted here in the first place!

Cheers!
Stewart[/quote]

Hey Stew,

Never seen the 6072 of different sizes, but out there the GE 5 stars is OK, for what it is.
To be honest, I don't quite understand why that tube got so popular--low transconductance, high plate impedance, lowish mu...
I'd try some NOS 12AT7--to my ears much more exciting tube... and much cheaper.

Best, M

Hi Mark,

Good to hear from you!

That's more the kind of idea I was hoping for.

The size thing is just a couple of mm, maybe even less, but it's enough to cause the trouble. I'll try to take some photos tonight or tomorrow.

S

The GE 5 star definitely fit, & sound peachy too !!

i know they are a little expensive but check www.tubeworld.com

they usually have some 5 stars, call them if there isnt anything that tickles your fancy on the website.

When I have time I will measure the 6072as and 12ay7s and 12at7s I have with a caliper I will post the H x D in mm and inches. Read what Marik posted.

Now if others do this instead of posting use a 5 star you will have something to add to the meta about what fits a C28a