Most preamps require that you turn them on to activate the HT bypass, tubes and SS. Yes this is of more concern with tubes, due to their shorter lifespan than transistors. I do know a gent who had his Gill Audio/Art Audio Alana tube preamp designed for a "true" HT bypass, in that he does not need to power up the preamp to have the bypass become active. A novel idea I think.
Also, as Ruebent states, most manufacturers can tell you their preamps 'unity gain' reading. Unity gain is the point in which the signal is neither cut nor boosted, as in a HT bypass. You could just use any of the preamps inputs, and set the volume to the manufacturer recommended unity gain position.
Cheers,
John
Also, as Ruebent states, most manufacturers can tell you their preamps 'unity gain' reading. Unity gain is the point in which the signal is neither cut nor boosted, as in a HT bypass. You could just use any of the preamps inputs, and set the volume to the manufacturer recommended unity gain position.
Cheers,
John