I had a preamp with a balance control (never used it) and was bypassed, it actually sounded better, transparency and detail improved. So any un-needed switch or pot that can be successfully removed from the signal path would be beneficial for sound quality. But you are in a unique situation where you can dispense with the preamp and use the amp's volume control plus have the ability to adjust the gain of the amp to match your particular preamp however that scenario does not offer any switching between components. If your technician is local I would insist on him making things right one way or the other.
DIY - replace volume control
My tube amp has a volume control. Since I use an active preamp, I simply leave the volume control on wide open all the time. (There is no switch anywhere to take it in/out of the signal path.) Recently, the amp went in for repair for an unrelated issue. Somehow, the technician managed to screw up the volume control by 'fixing' something that didn't need fixing. Now, I'm trying to figure out how to make lemonade out of lemons.
Would the sound be improved if I removed the volume control? Can I simply remove the pot and directly connect the wires that meet at the back? Or do I need to do something else? Thanks!
Would the sound be improved if I removed the volume control? Can I simply remove the pot and directly connect the wires that meet at the back? Or do I need to do something else? Thanks!