Did the guys at your audio club do any mods to the ANK DACs or are they great as there are?
The guys are mad scientists and are incapable of building anything stock.
Audionote DAC 5.1 Signature upgrades:
Silver (.999) signal wire 16 gauge, instead of 18 gauge supplied copper
High voltage and high current hookup wire 16 gauge
Printed assembly manual from latest released version online
Six 1/4 watt resistors on Super Regulator board replaced with 1 watt
Basic rubber feet replaced with large aluminium/rubber footers
Small rubber washers for mounting power transformers and chokes
Super-Reg board: United Chemi-con capacitors replaced with audio Elna Silmic of same values, sometimes higher voltage
Analog board: United Chemi-con capacitors replaced with audio Elna Silmic
RCA panel jack replaced with WBT RCA jack for aux S/PDIF connection (for looks really, who cares if it makes any difference I won't be running a CD transport any time soon)
Front-mounting rotary switch and gold knob optional addition instead of rear toggle on/off (I may not wire rear switch at all) Long 120v live run will be high grade sheilded and grounded
Replacement 5x20mm fusses (possibly better audio grade, but in my mind they are all pretty stupid)
Copper tape for making a flux band around the smaller choke (more a learning experience, not sure it will make a difference, but it shouldn't hurt)
V-Caps upgrade from Audionote caps, purchased from ANK (suggestion from Brian at ANK)
Fourteen Non-magnetic Tantalum resistors all replaced on analog board, from ANK (I love these resistors for signal paths)
I will use a familiar USB board: WaveIO with latest clock, opposed to supplied Chinese brand of questionable origin?
Added 5 volt power connector for outboard linear power supply instead of using USB cable with computer supplied voltage leg
I will experiment with different rectifier tubes besides the one supplied, 5Z3PJ (new), Jan5931 (NOS), WE274B (Psvane), 5U4G (whatever), etc
Experiment with the two analog tubes ECC82/12AU7 and ECC99 (EH, JJ, Sylvania, Phillips, etc)
Power transformers mounted in slightly different location with 90 degree turns
Aluminum panel with Mu-Metal shielding between digital/analog side and power supply side
I will also rout signal wires more directly, and for now not wire the balanced output connectors.
ANK DAC 5.1 Signature upgraded parts

The off the grid power supply for the music server and WaveIO USB board is a custom LiFePO4 battery power supply.
