No, has to be a 12au7 type!
OK thanks. Too bad have lots of them.
No, has to be a 12au7 type!
I moved to a pair of cryo'd NOS Mullard CV4003's a little over a week or so ago as well. I don't get any flashing/arcing with mine thankfully. Overall, very yummy.
I agree with the previous comments - a very resolving, detailed tube, that's tonally balanced with richly textured bass and superb impact. They've become my favorite WA7tp tube, and play well with all of my headphones. Both my LCD-2 and my HD800 sound tonally "right", which is saying something. The only "gripe" I have is that sibilance is very obvious if it's on the recording (particularly with the HD800, to no ones surprise). This is not a tube that glosses over recording flaws in the slightest. If you're looking for gooey "tube warmth", look elsewhere. However, if you want microdetail, resolution, texture, soundstaging & separation, and excellent timbre, this is the best I've heard. As l've spent time listening with these tubes, I keep picking up nuances and details that I hadn't heard before, oftentimes in the lower registers of the spectrum. The low end punch these tubes can exhibit still catches me off guard, with zero bass bloat. Quite impressive - and the end of the WA7tp tube-rolling journey for me.
Turns out that I've been using the CV4003's in the PSU for a while now. I agree with your evaluation - especially with regard to driving the HD800's. Trouble is that I find when using the EH 6C45 Gold Plated tubes in the amp the highs remain somewhat uncomfortable. Switching to Cryo Treated 6C45Pi tubes in the amp, I think that I get as close as possible to having the "gooey tube warmth" on the WA7.
got a second set of 4 Cryo-treated Mullards from Upscale Audio still in original boxes from great britain and very obviously never used, still with full clear printing on the tubes and shiney copper pins and they do not exhibit the same white strobe on power-up as the others I got from company b. The construction of the cans inside the tube look slightly different too, they don't have holes in them like the others.
That's where I bought mine as well. I like their grading, testing and labeling - knowing what you're getting is worth it IMO. Enjoy.
Just out of curiosity, what were your test rating #'s?
I noticed that when the power supply is right next to the main unit there is a buzzing sound but if there is 2-3 inches apart there is no buzzing. Any one else notice this?
Strange. Mine sit about 1" apart and there is no buzzing/noise whatsoever.
Same here, 1" apart and no noise of any kind.
I changed powercords and now the buzzing stopped thanks.
got a second set of 4 Cryo-treated Mullards from Upscale Audio still in original boxes from great britain and very obviously never used, still with full clear printing on the tubes and shiney copper pins and they do not exhibit the same white strobe on power-up as the others I got from company b. The construction of the cans inside the tube look slightly different too, they don't have holes in them like the others.
just curious do you have a pic of your tube collection? I swear you must have at least 20 pairs or so with all the backup pairs you order.