Most source components will sound better (more linear freq response, wider dynamic range) through a high quality pre-amp. Sometimes a source component will mate beautifully with an amp, most of the time the impedances vary with frequency, and not just one stated imedance, and the match isn't what the spec's would suggest.
But with any system, it's a "system", so use what works best.
But with any system, it's a "system", so use what works best.