Preamp with tone controls other then McIntosh C22

Parasound does. Fairly clean implementation but they're tilting rather than shelving.

Best,

E

Tone controls are usually implemented in two ways:

1. tilting. The FR goes up or down as it gets away from midrange.
2. Shelving. The entire treble or bass region goes up or down a maximum amount.

These are general assesments. Some of the best, in terms of features, were the older Yamaha series with built in parametrics.

"... to hear SQ difference between two high end pre-amps.  The differences are likely to be subtle."

Only if you don't know what you're doing. If you put together a system where the differences between well made, high end preamps are subtle, you really, really messed up. Its time to rethink your approach to audio.

erik_squires
Thanx, Eric. I was asking about tube preamp.

randy-11
Thanx, and yes I can't agree more - need to try it myself, applying major real estate formula: location, location, location - of components in the room I mean.