Hey all, I don't own an amp that uses tubes anymore so I have absolutely no use for these.
All are in good working condition, verified in my neighbor's Hartke HA3500 just yesterday, Oct 23rd.
Here's how I tested them: Installed tube into the amp, powered up amp and let the tube warm for 2 min. Without an instrument plugged in I set all of the treble controls in the eq and contour to max, compression at 0, and master at 7. Listened for hiss from the tweeter as I turned up the gain for the tube.
All 3 had some hiss at gain settings somewhere above 12, but none were what I would call noisy, just normal amp hiss.
Then I flattened all the tone controls, plugged in a Jazz bass and played each one a bit using fingers and a pick.
Here's my rundown on how they sounded:
First up is the Groove Tubes GT12AX7R.
This one has the flattest freq response, it didn't seem to have the top end of the Philips or the open bottom of the Tung Sol, but it is also the quietest, no hiss til gain hit 3 o'clock.
It was also the most difficult to OD, had to crank the gain to almost max, and it was not rewarding.
OD was harsh and glassy, not very responsive to touch, just goes from clean to buzzy fairly quick.
Maybe not a sought after audiophile quality tube, but it's very quiet and it works.
Good for V1 position if you aren't into OD'ing the preamp.
Second was the JAN Philips 12AX7WA.
This one has the best top end and mids response, hiss free til gain hit 1 o'clock.
Overdrives nicely with a soft purr, the smoothest OD of the 3.
The front end attack of each note seemed a bit sharper, esp with a pick.
I used this as the V1 in both my Mesa 400+ and BB750.
A fantastic USA made tube.
Last was the Tung Sol 12AX7 ECC803S.
This is the gold pin version, made in Russia.
Good freq response throughout, but the top is not quite as present as the Philips, but the bottom is smooth and thick.
Sounds really great with fingers and thumbing, nice pillowy bottom end without being boomy.
When pushed it has a bit of the buzz saw to it, but much more responsive and not as harsh as the GT.
Same as the Philips, a faint hiss started at about 1 o'clock.
I'm looking to sell them together, so I will not split them up.
They will ship in the plastic tubes pictured below, secured in a small cardboard box with a foam liner to keep them from bouncing around.
$50 shipped CONUS.
File size: 314 KB
File size: 302 KB
File size: 316.9 KB
File size: 326.7 KB