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Rolled some 12ax7's recently...

Hi All,
I went through my supply of 12ax7's recently and found some goodies.
I recently compared Bugle Boys to Telefunkens in the phono stage of my pre-amp. Interesting (to me, at least). I found the Telefunkens to be nice sounding; very clean and clear, very nice detail, over all a very nice sounding tube. The Bugle Boys, however, were magical! WOW! Timbre was so much more apparent. The soundstage depth and width increased; especially the depth. The music seemed to come alive and glow. It was much more captivating.
I found such a dramatic difference between two high quality tubes very interesting.
I have yet to try 10m's, and 70's Mullards that I found. I will report when I do...
By the way, NOS Sylvania's sound nice in the line-level stage. All tubes reported are vintage NOS. I match them with my tube tester. And, I do not change the volume setting between tube brands tested.
Any comments are more than welcomed! I appreciate any information on your experiences with 12ax7's. The price of some of these NOS is incredible; I am glad to have these nice examples in my collection!
Cheers.
bicycle_man
rodman99999
6,206 posts
 
Sounds like me. I should have stocked up on TungSol 6SN7GT/VT-231 Round Plates($50.00 ea, when I fell in love with them) while I had the chance. I was going to use three 6201's as phase splitter/drivers, but gave up on that amp after getting burned by the transformer builder(paid for, never received). Nothing I own now uses 6201's, so- I've never even heard these.
nsgarch's avatar
nsgarch
2,524 posts
 
R -- I know, don't ya just hate when that happens! ;-)
rodman99999
6,206 posts
 
Every time(you'd think I'd learn!). =8^(
bicycle_man OP
100 posts
 
Hi Clipper,
I have the BB 12ax7's in the phono stage, a BB 12at7 nearest the transformer, 2 Sylvania 12at7's near the can caps, and an unknown old stock 7025 in between (near the 6v4 rectifier).

The pre-amp sounds fine on tuner and both aux's, and of course, super fine on phono. I have repaired mine as many of the old Wima caps have dried out and wasted away.

I have also used the BB's in my Dynaco Pas3x and have found the same results as I previously described. The Fisher is not as forward sounding as the Dynaco, but it is, oh, so much sweeter! I was happy to see some Fishers selling on ebay for more than $450 in the last few months! As I recall, one of those was the 400-cx, which has a better following, but the other was a plain old 400-c. I have the 400-c. I like it and can't wait to get my Koetsu re-done -- should be mid-range luscious delight!
larryi
4,188 posts
 
In my phonostage (Viva Fono) I've tried a number of different 12AX7 variants. The Mullards sounded a bit veiled (muddy) for my particular application. In a friend's Tron phonostage, Mullards actually sounded oddly phasey.

I liked the sound of 5751s -- neutral, reasonably detailed and open on top. I did not notice a loss of gain, but, I wasn't looking at gain because gain and noise are not issues with my phonostage.

Telefunken 12AX7/ECC83s were also very good in my phonostage -- quite detailed, extended top and good harmonic density without being muddy sounding.

The Telefunken ECC803S is a very different animal from the other 12AX7s I tried -- incredible clarity and detail and explosive transients. It sounds a bit lean (less upper bass) and perhaps clinical, but, I made other minor compensating adjustments (primarily to VTA), and it is the very best tube for my application.

However, the ECC803S is WAY more expensive than the competition. For the money, a good pair of 5751s are hard to beat.
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