PS audio m1200

I am not an audiophile, but have spent like one.

I have the ref 6 paired with a Bryston 4 b cubed.

I find if I want to crank it up the volume flattens out.

It was relayed to me that the design of the volume control on the ref pre is the limiting factor, something to do with gain.

Will a more powerful amp solve this? I don't think so.

On that note does anyone know if that vole control on the ref 6 can be modified?

Mossy

Gain switch makes a difference, but the ceiling is still there.

Can't comment on input impedance. The pairing was suggested and confirmed by multiple dealers.

Will see if I can find a better match of amp for the ref 6