woollyjoe:
at circa 2k GBP, the chord is a bargain. Quite simply the best DAC you will hear. The 64 is great also and its a question of money. Your set up looks like you would benefit greatly from the DAC especially as the mac source is just not as good as a cd player.
Can I ask what the difference is in signature B&W speakers?
Yes, I'm very tempted by the thought of the QBD, and that's without hearing it!
Woolly Joe, I'm not quite sure what you are saying in relation to the Mac to DAC sound, when compared to the CDP to DAC sound. I have to say that the Mac is at least the equal of the Arcam. So I presume the newer Chord DAC would lift the whole performance of all digital stuff.
Regarding your speaker question: do you mean in relation to previous speakers? If so, incredible gains in all areas, most notably bass delivery. If you mean what's so different about the Signatures, then I'd have to know in relation to what exactly?