best solid state preamp from Audio Research?

All the solid state ARC preamps can be beat by other brands in the same price range!

ARC preamp design expertise is in tube or tube/FET hybrid preamps!

You don't see many SP-7 preamps for sale....and for good reason. A real vintage sleeper!

Nothing like a good consensus so the OP can make a wise choice.

My vote is for the LS-D.

The imaging is almost surreal.

Well, that should narrow it.

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The LS-10 is outstanding.
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I vote for LS3B,I have one since in a secondary system and I am very pleased.
George

I've had the LS3, LS9 and LS12. The LS12 sounded the best.

I liked the LS 9 I had for about a year and the only reason I sold it was because the volume control didn't have small enough incremental changes up and down. Sometimes the setting between one notch up or down on the volume would have sounded best. It provided a very large, transparent sound stage with good instrument placement in the sound stage.