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12AX7s [message #10071] Sun, 13 July 2008 02:10 Go to next message
James Christopher is currently offline  James Christopher
Messages: 6
Registered: May 2009
Esquire
The 12AX7 is hot again; prices for the very best are at or above the ridiculous prices charged for 6922 and 7308 types; moreover, dealers always have many more varieties and quantities of the formerly "unobtainium" 6922 and 7308s, while 12AX7s like longplate Amperex and Mullard often can't be had except as poor quality, noisy stock on ebay. This is an overview of the best NOS/Old production and a look at modern production 12AX7s

Re: 12AX7s [message #10072 is a reply to message #10071] Tue, 15 July 2008 14:26 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18669
Registered: January 2001
Illuminati (33rd Degree)

Yeah, I just recently bought a bunch of different ones, and was surprised at the variety of prices. Some were around $10.00, others were $25.00 - $50.00. Some were over $100.00. A few rare birds were nearly $400.00 for a matched pair.


Re: 12AX7s [message #10073 is a reply to message #10071] Thu, 17 July 2008 00:48 Go to previous messageGo to next message
James Christopher is currently offline  James Christopher
Messages: 6
Registered: May 2009
Esquire
OK-- This post is largely in response to a laughable "shootout" of 12AX7s performed by starry-eyed audiophools in Hong Kong. Their #1 12AX7 was the 1970-1975 10M series Mullard ECC83--hilarious, when the GOOD MullARDS like 17mm plate/square getter and even better (for balanced sonics and superior treble ambiance)copper-grid-post 14mm plate 1959-1965 production ECC83 were dismissed! The 10M Mullard is NO MORE than a selected 1970s (or 1968-1970)14mm plate Mullard 12AX7! Most 10M stock is actually later production 1967--1979, non-copper gridpost! These are vastly inferior to the 1960-1965 Mullards (overall, these 1960-1965 Mullards are the best 12AX7 ever made) but have brand cachet that blinds those that audition this mediocre tube. More to come: we examine RCA blackplates, longplate Mullards, blackplate Raytheon, Matsushita/Japan 12AX7 (factory and materials supplied by Mullard; among the best 12AX7s ever made) REAL Mullard 14mm plate, copper gridpost Mullard ECC83, 1959-1968 Amperex 14 mm plate, ECC803S Telefunken (looks like a 6DJ8 and sounds like crap) among others. Plus 7729 CBS, 12DT7 Raytheon, and other special 12AX7s. Most are no better than regular 12AX7s by same maker. One post per type; then we examine modern 12AX7s. I have 30+ types NOS 12AX7 in my collection; all will be examined. All 12AX7s auditioned in Audio Research SP8 MkII and SP6A-1 plus EAR 834P. Tune IN! Chris

Re: 12AX7s [message #10074 is a reply to message #10073] Thu, 17 July 2008 11:46 Go to previous messageGo to next message
Wayne Parham is currently offline  Wayne Parham
Messages: 18669
Registered: January 2001
Illuminati (33rd Degree)

I'd like to hear your impressions of each, so let me know when you write it up.

I have a half dozen of them in each price range. The only one I thought was terrible was the Sovtek. Sounds like they used rusty iron plates and pumped the exhaust of an old school bus inside 'em rather than pulling a vacuum. All the others I have sound good.

My favorite is an RCA, second favorite is GE. Electro-Harmonix is nice too. Tung-Sol doesn't do anything weird, sounds good. All these are new production but the RCA and GE, all used in an Audio Note Kit 2.

I'm thinking about trying a Telefunken. Your thoughts?


Re: 12AX7s [message #10076 is a reply to message #10071] Fri, 18 July 2008 01:13 Go to previous messageGo to next message
James Christopher is currently offline  James Christopher
Messages: 6
Registered: May 2009
Esquire
Evaluating old stock (NOS) 12AX7s is subjective, too much so, as it all depends on the system, music played, individual preference, etc. It would run to thousands of words just evaluating USA made 1947-1970 12AX7s.... and then there are the Eastern European, Western Euros, the surprisingly good Japanese made 12AX7s etc etc. As far as readily available, modern stuff.... that's simpler. None really compares to 90% of the old production, period. In the 1990s, the Ei/Yugoslavian copies of the smoothplate Telefunkens were fantastic; they had 95% of the Telefunken magic for $7 a tube. Even in 2001-2004, when Ei was in financial trouble and quality control went out the window, when you got a good Ei 12AX7 it was a great tube-- better than many of the humbly worshipped NOS types. I like the "Mullard reissue" 12AX7 sold by Groove tubes (it's a Chinese Shuguang). Likewise, what is known as the "C9, or 9th generation 12AX7B" by Shuguang is an OUTSTANDING 12AX7, with almost Mullard-like midrange (REAL British Mullard not Russian)and good soundstaging. I'll post a link to this and another version Chinese 12AX7-- best available. I like the LPS Sovtek, but DO NOT like the Electro-Harmonix/TungSol shortplate 12AX7s. I don't care for JJ 12AX7s. The Sovtek LPS has good sonic balance, but makes my gear sound like solid state. Flat, no texture to the mids.

Re: 12AX7s [message #10078 is a reply to message #10076] Fri, 18 July 2008 01:18 Go to previous message
James Christopher is currently offline  James Christopher
Messages: 6
Registered: May 2009
Esquire
http://cgi.ebay.com/New-Shuguang-12AX7B-7025B-ECC83-Vacuum-Tube-4pcs_W0QQitemZ350036735746QQcmdZViewItem?_trksid=p3286.m20.l1116
These are the Shuguangs. They have just a taste of Mullard to them; nothing comes close to the NOS Mullard, tho. These are pretty sweet sounding, a little dark in the treble, but smooth.

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