Tubes generally run less negative feedback, and those that run zero feedback will exhibit less surface noise than a typical transistor preamp that uses loop feedback. The reason has to do with high frequency oscillation, a ringing effect caused by the feedback itself. This ringing is set off by clicks and pops, which ring in the closed loop for far longer than the actual event.
Thus, the tube unit running zero feedback will appear to play less ticks and pops, even though its overall S/N might be less than that of the transistor unit. Try it sometime- you will see what I am talking about- in some cases this difference can be quite dramatic!
Thus, the tube unit running zero feedback will appear to play less ticks and pops, even though its overall S/N might be less than that of the transistor unit. Try it sometime- you will see what I am talking about- in some cases this difference can be quite dramatic!