Since your location should be Japan and you own so many models, I would like to ask some questions regarding the DC power jack.
For
BOSSFET V3 desktop amp,
which Oyaide DC power connector will fit the jack properly?
http://www.ebay.co.uk/itm/OYAIDE-DC-2-1G-AUDIOPHILE-GRADE-DC-POWER-PLUG-FITS-ARCAM-R-DAC-/150868469857
http://www.ebay.co.uk/itm/OYAIDE-DC-2-5G-AUDIOPHILE-GRADE-DC-POWER-PLUG-FITS-SQUEEZEBOX-TOUCH-/350584424390
5.5mm X 2.1mm (
Oyaide DC-2.1G)
5.5mm X 2.5mm (
Oyaide DC-2.5G)
My plan is building my own tower with 2 linear power supplies. That means I will ask someone to make a pair of DC power cables for both connections
http://item.taobao.com/item.htm?id=20394223497
Both DC power cables should look like these guys