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Adam79
04-12-2012, 11:51 PM
Hi. Sylvania 12ax7 preamp tubes haven't been on my radar until I came across some posting about the Sylvania 12ax7 long black plates (D getter) being the "holy grail" of 12ax7s. This distinction is usually reserved for Mullard 10Ms or Philips long plates (Heerlen, Holland).

I'm curious to hear what you guys over here think of these tubes.

Thanks,
-Adam

midnightlaundry
04-13-2012, 02:08 AM
I have a bunch. I think the D getter is the 50's variety. My experience seems to be that they have a lot of gain with a strong low and highend.

1moreknob
04-13-2012, 06:12 AM
Ive been testing a lot of tubes lately, both Pre-amp and power, NOS and new versions. What I've found is it all depends on the Amp and circuit. At tube that sounds great in a JTM45 (I really like NOS Amperex, made in Holland) is too bright in a Deluxe reverb.

In my DRRI, I put in a new set of jj 12ax7S. they are in expensive, and sound great to my ear. They tame the high end slightly, and are just big and full in the DRRI.

Timbre Wolf
04-13-2012, 07:01 AM
Hi. Sylvania 12ax7 preamp tubes haven't been on my radar until I came across some posting about the Sylvania 12ax7 long black plates (D getter) being the "holy grail" of 12ax7s. This distinction is usually reserved for Mullard 10Ms or Philips long plates (Heerlen, Holland).

I'm curious to hear what you guys over here think of these tubes.

Thanks,
-Adam

The long black-plate Sylvania 12AX7 from the early-'50s are wonderful, in my experience. You really have to be specific about which Sylvania 12AX7 variant your discussing, because they had widely-varying character. These first Sylvania 12AX7 break up much later than all others they made, and the mid-'50s short-plate variants (first black-plate, then gray-plate) are more clear than the later-'50s/early-'60s long gray-plate ones.

As for comparing to Mullard 10M... those are just short-plate Mullard 12AX7A, and the long black-plate Sylvania 12AX7 beats them to a pulp in any contest for clarity. The '50s Heerlen 12AX7 would still win that particular contest, but not by much, and with a different tonal character. Those Sylvanias are very balanced, tonally, throughout the frequency range.

Yes - the Sylvania long black-plate 12AX7 is worthy of attention.

- Thom

Adam79
05-03-2012, 11:26 PM
The long black-plate Sylvania 12AX7 from the early-'50s are wonderful, in my experience. You really have to be specific about which Sylvania 12AX7 variant your discussing, because they had widely-varying character. These first Sylvania 12AX7 break up much later than all others they made, and the mid-'50s short-plate variants (first black-plate, then gray-plate) are more clear than the later-'50s/early-'60s long gray-plate ones.



Check out the picture below. It has a square getter.

http://members.toast.net/adam79/sylvania12ax7.jpg