Actually, I found that putting Walker SST or SST Extreme carefully on tube pins (for me it is a C2200 pre), whether the stock tubes or replacement totally eliminates any tube noise. The Walker SST is pricey, and even though the little jar doesn't contain much it is more than enough to treat 10-15 complete audio systems.
Try this first before replacing your tubes, although I highly recommend replacing the stock tubes; doing so will transform to an entirely new, and higher, level of performance.
Try some NOS Telefunken ECC83(smooth plates), 50's or 60's Siemens or Telefunken ECC803S(expensive) in the phono section,for the ultimate in accuracy and low noise. The ECC803S was manufactured specifically with those attributes in mind. Amperex and Mullard ECC83's, of course, will add warmth, if you are looking for that. Be certain they are tested and guaranteed, Low Noise. I do endorse SST or Xtream AV Quicksilver(applied VERY carefully), but neither will help quiet a noisy/microphonic tube.
Jgiacalo...I will look in to the Walker SST as I am really trying to lower the noise floor on the MC phono section.
Rodman...where are you getting the tested and guaranteed Telefunkens from? I don't necessarily need added warmth--a more detailed/precise tube is preferred. I mostly want dead quiet! What benefits do you hear from using the SST or Xtream?
BTW--I am using VPI Aries 3 with Lyra Argo i cartridge and XLO Reference3 phono cable--if that helps any.
Herbies Tube dampers are also good for quieting microphonic tubes @ $13. They also have a 90 day full refund policy in case you don't like them. But I Think you'll keep them.
Talk to Andy
heck with guys at Audio Classics to see if they have done any experimenting.
The last time I bought anything upper crust from the 12AX7 family, in a Tele or Siemens, I got them from a seller in west Germany. He had his own website then, and I dealt with him a few times. Now he sells on eBay as 'audiotubes_de'. Very reliable and honest. He does have these listed currently:(http://cgi.ebay.com/2-NEW-NOS-Tubes-Siemens-Telefunken-ECC83-12AX7_W0QQitemZ160410679934QQcmdZViewItemQQptZVintage_Electronics_R2?hash=item255938ba7e) For a few years my tube compliment has consisted of Siemens CCa's(6), Tungsol 6SN7GT(RP-2) and Sylvania 6SN7W(tall bottles-2), so- I've not had occasion to hunt the 12AX7 woods for awhile. If you desire the clean sound you describe; stick with the early Tele and Siemens offerings(50's to early 60's). Happy listening!
You want to skip the 12AX7's altogather IMO (not that there aren't some quiet ones) but for REAL quiet and smooth, grainless, flat frequency response, you want matched triple-mica black plate 5751's, with the copper support rods and rectangular getters. My personal favorites (of that type) are the 50's and early 60's Sylvanias (~$200 - $250 a pair) or RCA's (~$150 - $200 a pair).
Some facts on subbing the 5751 for the 12AX7: (http://www.upscaleaudio.com/GE-5751_p_47.html) (http://thetubestore.com/gainfactor.html) NOTE: What is said about changing the sound of a guitar amp will also apply to an audio circuit. Bottom line: It will be a matter of taste.
Thanks Rodman...both of those links were helpful
Nsgarch...i will read up on the 5751. It looks like there is about 30% less gain with this tube--hence the quiet.
I agree with cpk, give Andy at VTS a call. Also, you can check Music Reference/RAM Labs who also sell low noise and well matched tubes.
FWIW I just bought a Music Reference RM-10 MkII and it uses 12AX7 tubes. I can swap in 5751's, but to work optimally a couple minor changes to the circuit have to be made. So it's not always plug and play.
All the NOS tubes I've tried from UA (maybe a dozen or so) have been weak and overpriced! And their remarks about 5751 are incorrect from an audiophile POV. (Might apply to guitar players overdriving their amps to get that "fuzzy" sound they like.)
Regarding the "fact" that 5751's have 70% the gain of 12AX7's: First of all, 5751's were initially designed for military use (the 3-mica version, anyway) and the Air Force wasn't going sub tubes which couldn't PERFORM the same as regular 12AX7's. Second, most circuit designers would never ask any tube to operate in the range (top of the curve) where that extra 30% would be a factor; and third, the best examples of 5751's (like the RCA's and Sylvania's I mentioned earlier,) if really new old stock, or almost new old stock, have transconductance readings way above the "average normal". The AN for a 12AX7/5751, for example is 1250 micromhos. All my good ones read 1300 (minimum) and most are 1500 +/-. So I wouldn't let the 70% thing bother you if you're buying premium NOS 5751's (but don't buy them from UA ;-) I also caution against buying really 'brand new' (never used) vintage tubes. You could be spending a lot of money for something that pops the first time you power it up. I have purchased truly NOS tubes, but insist the seller run them in a piece of equipment for an hour before shipping them to me ;--)
For those unfamiliar with "Joe's Tube Lore", this rundown on 9-pin twin triodes, is highly recommended as a place to get your feet wet. It's where I started, and a good guide to future exploration: http://www.audioasylum.com/scripts/d.pl?audio/faq/joes-tubes.html
Joe's Tube Lore is a great place to start learning about tubes in general. I have several of the tubes he has referenced, especially 5751's.
I'd like nothing more than to use some of the 5751 tubes I have lying around. Maybe I'll give them a try anyway.
I agree about UA. I've bought from them twice, but not a third time, no way.
I've only purchased power tubes from Upscale(NOS and new production, over the past 12 years), and have had nothing but good experiences and performance. Never small signal tubes, so- no comment there. I HAVE BEEN purchasing NOS small signal tubes(Mullards, Teles, Siemens, etc, from the 40's through the early 60's) for decades, and HAVE NEVER had one go south, even after years of use. I'm simply careful, regarding from whom I buy them. Whatever you choose to do(Cajunpepe), don't pass up listening to the Tele ECC83 smooth plates, at least.