miss matched 12AX7,s
- Thread starter rjag46
- Start date
Register to hide this ad
Depends where and how they are used. If you've got one tube for left and one for right, having mismatched tubes may give a slightly different sound in the left and right channel. If they're used in series though, like one half of each tube is right, one half is left and they feed one into the next, it won't matter. Electrically it won't hurt anything, but sound-wise you may hear a slight difference. Play around with different combos until you find something that sounds good to you.
The A suffix just means controlled warmup time. They're totally interchangeable in most circuits that aren't series wired. Basically unless you are running them in an old TV, it doesn't make any difference.
The A suffix just means controlled warmup time. They're totally interchangeable in most circuits that aren't series wired. Basically unless you are running them in an old TV, it doesn't make any difference.
Going from left to right, from the pictures above... tubes 1, 4, 5 and 6 are essentially the same tube (RCA). Blackplate vs. gray plate won't make much difference in the sound, IME.
2 and 3 are the odd ones out. If you can find one more tube somewhere, that matches either one of those, you can have another pair.
In that amp, there are three pairs. If you're looking over into the inside of the amp from the front (front panel closest to you), the far left two are, IIRC, the phono stage (I'd put tubes 4 and 5 there), the middle two are the preamp/tone stage (I'd put 1 and 6 there), and the right hand two (closest to the power transformer and rectifier tube) are the amp driver (I'd put the two mis-matched ones there, until you can match one or the other of them).
That should minimize any difference in sound, due to the tubes not being exactly the same...
Regards,
Gordon.
2 and 3 are the odd ones out. If you can find one more tube somewhere, that matches either one of those, you can have another pair.
In that amp, there are three pairs. If you're looking over into the inside of the amp from the front (front panel closest to you), the far left two are, IIRC, the phono stage (I'd put tubes 4 and 5 there), the middle two are the preamp/tone stage (I'd put 1 and 6 there), and the right hand two (closest to the power transformer and rectifier tube) are the amp driver (I'd put the two mis-matched ones there, until you can match one or the other of them).
That should minimize any difference in sound, due to the tubes not being exactly the same...
Regards,
Gordon.
