Hi all - My amp configuration is a bit different than some, and uses a hybrid bi-amp (tri-amp?) approach.

I use two old Dynaco 70s with the VTA mods/pcbs, as single channel monoblocks (one channel from each amp). Other mods include Roy Mottram's solid state copper rectifier, and the coupling caps are from Convergent Audio. There's a 12BH7s in the center, and RCA clear top 12AU7s in the wings, and Tung Sol 7581A outputs running in triode for about 17 wpc. These amps currently drive only the midbass and tweeter of my old Sterling Acoustics Acumen II speakers.

About 18 months ago, I split up the duties of driving the main speakers by adding a vintage Kenwood integrated amp to drive the main woofers below 80hz, and send power to a powered Definitive Technology subwoofer. The speakers original passive woofer crossover has been bypassed, and an active low pass crossover was put in-line with the Kenwood, which seems to me to be the best of both worlds....sweet clarity of tubes on the mids/highs, SS driving the woofers with authority.

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