I just posted this over on http://music-electronics-forum.com/ and thought it might be of interest over here:
This is a very useful tube for a lot of amp applications, with one half of a 12AX7 and one half of a 12AU7 in the same envelope. JJ is currently making a version as the ECC832, and also offers a version with the sections reversed. It has no officially recognized international designation, but JJ calls it an "ECC823." I think it might be VERY interesting to harpers who want a lower gain tube in the first stage of an amp but don't need to drop two stages to such low gain as a 12AU7's. Or for anyone who needs a lower gain than a 12AX7 in a single stage. I'm sure you can think of many other situations where this combo would be very useful, such as a reverb drive and recovery tube.
Here is the JJ spec sheet for their version(s) of this tube: http://www.jj-electronic.sk/pdf/ECC%20832.pdf
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"A cheerful heart is good medicine."
