I'm also one considering to "potentially" upgrade my ODAC sometime along the future.
My current setup is an ODAC + O2 combo, with HD650's
The questions I have however, arises from my absolute inability to detect any sort of "noise" from the system. Which means (to me) it's clean enough for my enjoyment. If we remove "reduction of noise" out of the equation, then what sort of improvements could I notice from using devices such as the iFi iUSB?
If the changes are too little to even consider, would it be better to just save up for a Bifrost Uber Gen 2 USB DAC?
My decisions and questions come from reading this FlySweep's post: http://www.head-fi.org/t/661444/schiit-bifrost-uber-analog-upgrade/390#post_9704321 , which also includes the BH Crack, something in which I am going to save up for.
*Edit: I'm also going to include the Aqvox USB Low-Noise Power Supply in this question, which seems to be nearly half the price of the iFi iUSB*
Edited by JacobLee89 - 1/28/14 at 3:21pm