How much do I need to spend to get a preamp that sounds better than no preamp?

There's no technical reason to conclude getting gain in a pre-amp stage won't sound better.

Sure there is. Gain means an active circuit. And all active circuits add noise, distortion, phase and frequency distortions. If you don’t need the gain from the preamp, you can avoid these problems by eliminating the preamp. 

Thanks aball. Trying it now.
Ben

My point was that one way or another, you do need gain, no matter what you want to call it, or which box you think it should be in, or not be in. Most amps have 2 or 3 stages of gain, even if you think there’s only one.

Also, a volume control will add noise, crosstalk, and phase error. You don’t need gain to screw things up. And some volume controls do more damage than multiple amp stages would.

Ben - you’re welcome! Let me know how it goes.

You can just put the gain control at some random point like 3:00, but is that the optimal point? Not clear. One would need to know a lot about the circuit design to make that call. I’m not surprised AI isn’t getting involved in the answer, as it can be quite complicated. It’s also why few amplifiers actually have gain controls (except for vintage ones, and that was because of the wide variety of speaker efficiencies back then).

I would have thought the least amount noise would come if the master is at or near full for loud listening, then the gain level if it is controlling the "tube gain" it’s then only increasing any noise to a minium level, as tube noise/distortion increases at the same rate as the gain will.

Cheers George