Home » Audio » Thermionic Emissions » New production 12AX7s
New production 12AX7s [message #9894] Sun, 21 January 2007 20:47 Go to next message
Bill Epstein is currently offline  Bill Epstein
Messages: 1088
Registered: May 2009
Location: Smoky Mts. USA
Illuminati (2nd Degree)
I'm breaking in 2 pairs, Sovtek 12AX7LPS and Tung-sols. Driver tubes in the Cornet phono stage.

They are quite different. The LPS' aew balanced and a bit cool: Telefunken-ish. The T-S have more bass weight and the most gorgeous Amperex-ish mid-range.

Re: New production 12AX7s [message #9895 is a reply to message #9894] Mon, 22 January 2007 12:05 Go to previous messageGo to next message
Shane is currently offline  Shane
Messages: 1117
Registered: May 2009
Illuminati (3rd Degree)
I ran the Sovteks in my 5150 guitar amp --5 of em'. They were the stock tubes and always sounded grainy and noisy using the clean channel with a bad "bite" at the high end when distortion was kicked in-- for lack of better descriptions. Replaced them with JJ's where one was voiced to be warmer in the clean section. They just blew the Sovteks away in both noise and overall sound. Course this is high gain guitar stuff and not hi-fi. I just gave all the Sovteks away a couple months ago.

Re: New production 12AX7s [message #9896 is a reply to message #9895] Tue, 23 January 2007 00:09 Go to previous messageGo to next message
Thermionic is currently offline  Thermionic
Messages: 208
Registered: May 2009
Master
Hi Shane,

Out of curiosity, were the Sovteks indeed the 12AX7LPS? Typically the LPS sounds as smooth or smoother than JJ 12AX7s and is very quiet unless you put 'em in a high powered combo amp and crank it up, because those looooong plates will resonate.

OTOH, the Sovtek 12AX7 WA and WB are just as you described, grainy, harsh, and noisy. JJ 'AX7's will slaughter 'em. If I'm not mistaken, one of those is the stock preamp tube in the 5150 nowadays, or else they used to be.

Thermionic

Re: New production 12AX7s [message #9897 is a reply to message #9896] Tue, 23 January 2007 14:45 Go to previous messageGo to next message
Shane is currently offline  Shane
Messages: 1117
Registered: May 2009
Illuminati (3rd Degree)
They were indeed 12AX7LPS's. This amp is the 5150 combo and obviously the tubes got worse sounding with more play due to the tremendous vibration, but they never sounded good from the get-go. I got the JJ's at Eurotubes. I don't remember which one was "voiced" a little different, but just popping that one tube in place of the Sovtek was like night and day. I just replaced all 5 12AX7LPS's with the JJ's as well as the Sovtek power tubes for JJ's. It would be interesting to hear some NOS Tung-Sols in the power section.

Re: New production 12AX7s [message #9898 is a reply to message #9897] Wed, 24 January 2007 15:47 Go to previous message
Thermionic is currently offline  Thermionic
Messages: 208
Registered: May 2009
Master
Thanks Shane, I appreciate your response.

Sylvania STR386 6L6GCs would sound fantastic in that amp, if you could lay your hands on some. I know, I've heard them in a 5150 before. It was the original tube the amp came out with, until Peavey's stock dwindled. Peavey had commissioned an entire production run of the 6L6s from Sylvania way back when, but by the time the 5150 came out it was the only Peavey amp they were installing them in. You even had to show proof of 5150 ownership to get replacement Sylvanias from Peavey.

That was a marvelous sounding tube. IMO, they were the best sounding 6L6GC I've ever used in guitar amps, regardless of the amplifier. I wish I knew then what I know now, because I pitched many sets that just had the new worn off them and replaced them with brand new ones. When I was a youngster, you could buy them for only $15/pr, so once they lost a little tone you could pitch them. Now, they're nonexistent.

A friend of mine who owns a Peavey dealership has tons of them stashed back, but won't part with a single one. He has done both ear and electrical testing on well used ones versus new production 6L6GCs. The worn Sylvanias trump the brand new current production! How sad you can't get tubes like that any more. The closest thing I've heard to them is the winged C SED 6L6GC (which was patterend after the Sylvania), but it's just not the same.

Thermionic

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