One aspect often getting lost is the relationship between driver and power tubes. On my Wavac EC300b I use different driver tubes depending on which 300b tube I am using.
With Takatsukis the best result is achieved with Tungsol 6l6G coke bottles, using more high powered 6L6GCs (eg. JAN Philips 7581a or Svetlana Winged Cs) results in an overblown, harsh sound. Conversely using EAT 300bs with the coke bottles doesn’t work, resulting in early clipping and constrained dynamics. The EATs work best with Svelana Winged Cs, the even more high powered 7581as still feel overblown.
Given these findings, taking single power tube tests at face value without referencing the driver tubes seems problematic.
With Takatsukis the best result is achieved with Tungsol 6l6G coke bottles, using more high powered 6L6GCs (eg. JAN Philips 7581a or Svetlana Winged Cs) results in an overblown, harsh sound. Conversely using EAT 300bs with the coke bottles doesn’t work, resulting in early clipping and constrained dynamics. The EATs work best with Svelana Winged Cs, the even more high powered 7581as still feel overblown.
Given these findings, taking single power tube tests at face value without referencing the driver tubes seems problematic.