Who needs a Preamp??

I have always said and experienced that there is nothing like a good preamp in a system. YMMV but my systems have always sounded best with an active preamp.

I will remind folks that The Truth preamp is a wonderful option with an input impedance of 6 trillion ohms and and output impedance of 3 ohms.  If your source puts out 1.5v or more of output, then you are good to go.  They all do today. No impedance issues to deal with.  In terms of the amp you pair with it, ideally it should be relatively sensitive with full volume attained with under 2 or so volts.  

You can use 30 foot long ICs with no issue.  Worth looking into for $1000. 

A "Good" Quality Active Pre-Amp brings the "Life, Soul, Emotion" to the Music.

Technically, seldom needed, but a lot of music played through my Modwright 36.5 in the chain produces an emotional response in me that is kinda like the first bite of a hot fudge sunday...an "ahhh."  The 36.5 replaced the output attenuuator in a high-end DAC.

George says:

It adds coloration that some may like. 

Bingo. Every single component in the world is subtractive. The very, very best subtract (distort) very little. Some distort a lot but with euphonic distortion (ok the world champ in that regard is the sounding board of a boesendorfer piano, but I digress).
The real issue is that most digital volume controls are truly awful. A couple of weeks back i posted a great PPT deck (from ESS tech) on the whys and the measurements.  want to make your 16/44 digital into 10 bit sound? use many digital volume controls. And we aorry about 192/24?  LOL!!!!!!! or am i crying?

That said, the Oppo may in fact use the ESS chip. If they apply digital control in the 32 bit core, it can be almost transparent. But you must check very carefully, and polls on Audiogon don't change the facts. Check how they go about it.
G