Brdsmith, having just come off a high from trying what I am about to relate, in a friend's system, I am keen to share. That stridency you mention with the SS Bryston may be curable at least in part, with the Ayre Acoustics tuning disc, "Irrational but Efficacious".
The business part of this disc is simply a 5-minute tone that sweeps from below to above audibility. You may well have tried it before and if so, I didn't say anything. If not, well, you just play it occasionally, at moderate volume ( because it can exercise your woofers fairly strenuously ).
The result in a friend's system with a Benchmark DAC feeding a GamuT power amp directly ( no preamp ) and Gradient speakers was a very noticeable reduction in hardness and glassiness. This was the first time I had heard the disc used on a SS amp and it really worked well. It might work for you if you haven't tried it.
The business part of this disc is simply a 5-minute tone that sweeps from below to above audibility. You may well have tried it before and if so, I didn't say anything. If not, well, you just play it occasionally, at moderate volume ( because it can exercise your woofers fairly strenuously ).
The result in a friend's system with a Benchmark DAC feeding a GamuT power amp directly ( no preamp ) and Gradient speakers was a very noticeable reduction in hardness and glassiness. This was the first time I had heard the disc used on a SS amp and it really worked well. It might work for you if you haven't tried it.