Great, thanks oldhvymec! Learning as I go.
Ok to substitute 12AX7 for 5751 tubes in CJ Amp?
Hi Folks.
Despite having owned my Conrad Johnson Premier 12 tube monoblocks for over 20 years, I'm just starting to play around with tube rolling recently. (Previously, when a tube got tired I'd just replace them with whatever CJ recommended at the time).
Playing around with the input tubes: The CJs come with 5751s (I've been using GE), and as I understand it 12AX7 tubes are higher gain. However, are they not interchangeable in most cases? Just don't want to screw anything up in my amp.
Thanks.
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- 28 posts total
@oldhvymec : a 5751 is NOT a 12AU7! And cannot be subbed for one! A 5751 is a lower-gain low-noise version of a 12AX7, with the same current rating. They are interchangeable. The best versions have three micas and low microphonics. The 12AU7 has a much higher current rating and is used in driver stages. I own examples of all three of these tubes! |
+1 @atmasphere ! Sticking to the original tubes is always best! When buying 5751’s always try to buy the 3 mica version. The 2 mica version has poorer resistance to microphonics. |
+1 @facten : A man who knows his tubes! I own many of those 12AU7 sub's! |
- 28 posts total