what double triode is less microphonic ?

[inertial]

Hi,

More accurately, I'm searching info about a near zero microphonic medium mu double triode. Low Rp is requested.
candidates are
E182 CC , ECC99, 5687, 6H30 or others
I have some E288CC philips SQ but they ring like bells
I can considerate also single triode.
I know EC8020 is the best but they are ultra expansive !
I appreciate any kind of suggestion
Thanks for help,

Paolo

[Frank Berry]

Have your tried a 6922?

[inertial]

Yes frank,
my sowtek is perfect but I would just half Rp .
The problem seems to me that these sovtek 6922 are sort of unique,
others brand ECC88 are more or less microphonic.

cheers,

[cypher]

I'm using 6n6p which is replacement for E182CC and CV5766 and this tube doesn’t microphonic at all. And sounds very very good.. ;-))

[inertial]

Hi cypher,

please what is the brand of the your 6n6p ? Looks very interesting

[cypher]

6n6p this is NOS Russian tube, easy to find on eBay ant very cheap to. I don't really know name of company which was making them.
BTW. Also 6n1p-ew (military version) is very good tube ;-))

[inertial]

Thanks cypher, very appreciated info

[inertial]

Cypher,

excuse me, is it 6n6p pinout the same of E182CC ?

Paolo

[Wavebourn]

A pair of 6J32P triode strapped is the best double triode in terms of microphonics.

[kenpeter]

I xray'd some Amperex, Sylvania, and Telefunken 6dj8's.
Most also bearing the ECC88 stamp. In the thread "I
got waay too many 6dj8's" you will find more photos.

My observation was that the plate structure viewed
straight down from top (right through the getter),
the plate looked like a weirldy bent tuning fork, or C
with sligthly overlapping ends that don't actually touch.

Unless the insulator at top or bottom has a grip that
is effective to damp out that mode, the plate itself is
not a complete closed circle, what supports the open
end of the tuning fork?

---------------------edit-------------------------

I think this was the relevant angle of view