Joe's Tube Lore is an excellent guide, though I have found quite a few tubes to vary from his descriptions, depending upon the component used. In two different amps, for example, the Mullard 2493 (6922 equivalent) sounded much more balanced and tonally pure than either the Amperex Pinched Waist or the Telefunken CCa. A friend and I also heard the Pinched Waist in his DAC, and they sounded more etched than his stock tubes. Go figure. I have yet to find an Amperex (save for a 6X4 rectifier) that didn't sound too bass heavy...could be the room, who knows?
The guides are useful, for sure, but your own ears will be the final judge.
Now, the Siemens 1960s (not 1970s) CCa's...yeah, those are sweeeeeet! Definitely get the MBG, however, in case they are microphonic.
The guides are useful, for sure, but your own ears will be the final judge.
Now, the Siemens 1960s (not 1970s) CCa's...yeah, those are sweeeeeet! Definitely get the MBG, however, in case they are microphonic.