Is no preamp really better that a good preamp?

09-26-15: Rustler
I guess my final question, then, is what kinds of specs should I look for in a preamp if I want to add one at some point?

Ah!! now that's another ball game, if you want to colour the sound in some way instead what you get going direct, this will be a bit of a merry go round, as all preamps have different sound signatures, and no one here could give you the right answer to which to get unless they are you.

Cheers George

It's not really about the specs, although impedance matching should be considered. Go back and read Atama-Sphere's response. Pay attention to #3 and #4. IMO If you do not need the gain, the source variable output section can control the interconnect, and you like the sound then you should stop there.

09-26-15: Clio09
If you do not need the gain, the source variable output section can control the interconnect, and you like the sound then you should stop there.

Correct Clio,
Once again, please anyone who wants to put their head on the chopping block.
Using and quoting the laws of electronics (not just voodoo speak) what is not matched with the OP's PS Audio Dac 100ohm 2.8v output running direct into the Spectron's 50kohm 26db of gain input.

Cheers George

Wait! Do we have George and Ralph agreeing on something? Guess that loud cracking sound noise I just heard was hell freezing over ;-).

No freezing, just that warm feeling of not having to empty your pockets on an added active preamp that not needed under these conditions, and probably going forward with the sound instead of backward in the process.

Cheers George