I don't believe the market is large enough or you would find the behemoth companies exploiting it. The multichannel processors all have stereo capability so where is the market for two channel only if you have to supply amps too. One of the attractions of the 2150 is the honest power supplied by its amps at a decent price range. If we based a preamp on the 2150 it would still be priced similarly. Now, you would be essentially doubling the price for a combo which will only give 3-4 db higher SPL.
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Music system
Model 990/7500/Magnepan 1.6 QRs/Technics SL1200 MK2/Aperion S-12 Subwoofer/OWA3/Sony NS75H DVD
APC H15 Power Conditioner

TV System
Large Advent Loudspeakers/ Polk center/Monoprice surrounds/Panasonic Viera 42 inch/Onkyo HT-RC260/Sony BDP S590/Directv


Home Theater System
Onkyo PR-SC886/Outlaw 7125 Klipsch RF-82 L/R,RC-62 center, RB-35 SR/SL, BENQ HT1075, Outlaw LFM1-EX/OPPO BDP-83/Directv
Harmony ONE
Blue Jeans and Monoprice interconnects
APC H15 Power Conditioner