For those looking for 12AU7 sub-types.

75.140.84.148

Posted on May 28, 2017 at 16:29:15

These are the ones I've had most success with. Lightly gray glass, black plate, square getter ring Hytron made 7318 tubes. Often labeled CBS-Hytron or National. Think they are late 1950s, early 1960s era tubes.

Rich tone. Good in phase inverter position.

photo 7318 CBS Hytron_zps9sspu5sq.jpg

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RE: For those looking for 12AU7 sub-types.

Mechans

16:54:52 05/29/17

RE: For those looking for 12AU7 sub-types.

FenderLover

23:17:37 05/29/17

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RE: For those looking for 12AU7 sub-types.

Mechans

16:54:52 05/29/17

RE: For those looking for 12AU7 sub-types.

FenderLover

23:17:37 05/29/17

RE: For those looking for 12AU7 sub-types., posted on May 29, 2017 at 16:54:52
Mechans Audiophile Posts: 1804 Location: East Coast Joined: May 23, 2004	I have been looking for 7318s for a long, long, while and never found anything that seemed real . I never thought of them as black glass tubes but more as a refinement of the 7316s. Which I have a number of variants of. I have a couple of black 12AU7s The sleeve you have provided is most convincing I must admit. And So my search goes on- All I can say is WOW -What A Find-

RE: For those looking for 12AU7 sub-types., posted on May 29, 2017 at 23:17:37
FenderLover	Thanks! I found them in my stash. Must have bought them years ago. These test higher and sound much better than even the CBS-Hytron 5418A I've tried. The 7318 is crazy good in an Ampeg V22 amp I redid. That amps runs 7027A output tubes. Very, very, very good tubes. RCA black plates.

Tubes Asylum

For those looking for 12AU7 sub-types.

75.140.84.148