Do I really need a preamp?

Mapman is right with proper mating with passives.

And as I have stated many times.

If you decide to give a 10kohm passive a try, such as the very affordable $49.00 Schitt SYS passive pre. http://schiit.com/products/sys-passive-preamp,
the only proviso to look for to give them a great match are.

1: Interconnect to power amp to be low capacitance (<100pf per foot) which most good quality one are, and 3mts or less long.

2: Tube output sources can be a problem if higher than 1kohm output impedance, solid state sources are normally never a problem.

3: Input impedance of the power amp should be 33kohm or higher, which most are (47kohm being the standard).

If you have these, which 99% of systems are, then you can reap the benefits of the transparency and dynamics that a passive will bring to your system.

Cheers George

Robcentola hi,

Almarg (Al) is correct, technically, going direct and using the built in digital volume control of your Dac2, in my opinion will be the most transparent/dynamic way of getting the sound from your source to your speakers, without added colourations of a preamp.

If you find after doing it you would like to "voice " that sound a little, then for no cost you can position your speaker a touch differently
eg: toe them in or out a little, or move them closer or further from the back wall.
Or for some cost you can try different interconnects or speaker cable.

These suggestions are far cheaper than taking a punt on a preamp that costs $K's in the hope it has the right set of colourations for you, as they do all sound different to each other, because they all have their own set of colourations.

Cheers George

I believe even in Stereophile John Atkinson states 47k-51k input impedance has been an unofficial input impedance standard now for over 50 years for most home audio S/S products input resistances. Since it was made the standard for MM cartridge loading way back and they followed suit with preamp and poweramps at 47k-51k.

Tube amps have even higher up to and higher than 100kohm which is even better for higher value passives like 20kohm ones.

As for the very few amps that are 10k that many tube preamps won't drive, they constitute probably less than 1%
of the market share.

Cheers George