Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: TerryD on April 24, 2014, 01:33:53 pm
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These were in the vibrolux I got. There are three of them and between them all, I can just make out that they are Amperex and then there is a number in grey on the bottom that says 49H2.Any idea what exactly they are? I'm hoping 12AX7s vs any of the alternatives.
Also, there are Sylvania 6L6s in there. What is their reputation, soundwise?
I havn't played the amp with these in yet as I was getting it going with newer tubes to get started.
Thanks,
Terry
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These were in the vibrolux I got. There are three of them and between them all, I can just make out that they are Amperex and then there is a number in grey on the bottom that says 49H2.Any idea what exactly they are? I'm hoping 12AX7s vs any of the alternatives.
Post a photo. Or take a hi-res photo, put on photobucket and post a link here.
Amperex was part of the Philips conglomerate. 80-90% chance that the "49H2" you describe is not the type-number of the tube (like 12AX7) but part of a factory and batch code system. With a picture, I can tell for sure.
Question: Is the "4" leading "49H2" really a right-triangle? It will look like a "4" but without the stem on the bottom.
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I'm not sure these will work for you. Yes the first doohickie is a diamond and not a 4. I knew this is not a type number, but didn't know if someone could tell from that. Terry
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Those are Amperex 12AX7's, probably made 2nd week of July 1969 in Heerlen, Holland.
That triangle is a right triangle, which makes a difference. See the Philips Factory Codes (http://eastwoodamps.com/PhilipsCodes.pdf) sheet.
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Great. I'll take those. Thanks again.