This might be the Passive Preamp im looking for
The best sound/value passive at the moment is the Schiit Sys at $49 with 30 day trial period.
http://www.schiit.com/products/sys
And if you need one with selectable on the fly tube, solid state or passive output configuration, their Freya model is great value as it has 3 inputs 128 position relay volume control balance or se output and inputs all with remote control
http://www.schiit.com/products/freya
Cheers George