Hi-fi's too important to leave it to the experts, Col :-\
Expert = Has Been, Dripping Tap, maybe.
PS I challenge anyone to find a setup with more 'PRaT' and ability to hold the tune together, but with sophistication and ability to preserve tonal colour, than an NVA AP10H / Grado RS-1 combo.
I'm surprised there aren't more DIY amplifier kits on the marker. For example where you buy a pre-built PCB, then select things like case and transformer size, different quality of internal wiring and detailed/simple instructions on building. The raw material costs in most DACs and Amps seems cheap so it feels like there is a gap in the market. The DDDac for example looks like a great piece of kit, but I do think the online ordering process and information on building could be better.