My understanding is that the power suply upgrade will increase the dynamics of the Dac1. For more info and a good deal on a new piece, email Jonathon@GoldmanAudio.Com I spoke to him about it yesterday.
Bel Canto DAC 1 Upgrade
Here is a copy of the email I recieved from Bel Canto inquiring as to new upgrade for those interested: "Yes, upgrades are now available. Return your unit with a note requesting the upgrade, include a return shipping address with a check for $150.00. We will complete the upgrade in a couple of days. Regards, Michael " Guess they have to keep up with that Full Nelson on the MSB. Charlie