For me it depends on the actual application for that particular driver tube. So do I need trace matched or not , depends on the application. Recently I’ve been tube rolling with the 12AX7 phase tube that feeds the two 12AU7’s in my mono blocks. What I’m finding there is I’m better of going to a lower mu substitute which lowers the noise floor of the amp. Although my pre has five gain settings in addition to the actual volume control , the lower mu tubes ( 12AT7, 12AY7 ) make a noticeable difference. Cheers , Mike B.
Are driver tubes as critical as gain stage tubes?
In an amplifier, do driver tubes need to be matched, balanced, like new, or quiet? For example, is noise as important in a driver tube as it usually is in a gain stage tube? If you must allocate resources among various tubes in an amp, where are the driver tubes in the heirarchy?