Atma-Sphere OTL amps deliver the tightest and most articulate bass of any amps I've heard; all the positive benefits of solid state control with the ability to reproduce harmonic overtones, timbre and resolution only seen with the best tubes. Unfortunately for your budget limit, you'll probably not find an M-60 MkII under $2500 (and the MA-1 for considerably more). But if you're able to stretch your budget and if you have a speaker compatible with the M-60, I think you'd find what you're looking for.
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