SS amp with tight deep bass ?

The EE pre-amp has a 1.5k Ohm output impedance. A Bryston would have too low an input impedance for it, resulting in lean bass. Look for something with a high input impedance, say 100k Ohm.

You should be able to find an Eagle 2A for $1K or less. Hard to beat for bass.

That EE pre has a whoppingly high output impedance. I don't know if they are the only ones, but the only ss amps that come to my mind, that have an appropriately high input impedance that might work your chosen pre., are some of the Electrocompaniets.

The specs shown here indicate an output impedance of 700 ohms, although reviews from some years ago indicate 1.5K.

I would suggest that you try to obtain clarification of that discrepancy from the manufacturer or importer, and, as Bob suggested, try to determine the worst case (highest) output impedance within the range of audible frequencies, which probably occurs at 20Hz.

Regards,
-- Al