iFi Bundle includes the ZEN DAC Signature usb + Zen CAN Signature + 4.4mm - 4.4mm balanced interconnect to link the two components, making one very high performance usb dac/amp combo for under $1000. (Retail price of each unit is $399 for dac or amp, $99 for cable)
ZEN DAC Signature is an improved version of the ZEN DAC, with the headphone section removed and improved parts used in the analogue output, to provide improved sound quality. The ZEN CAN Sig. also uses improved quality analogue parts and is a fully balanced design. It has 6.5mm and balanced 4.4mm output for headphones. ZEN CAN Sig. also has a XSpace feature, to broaden the soundstage and a HD6xx EQ feature, designed to be an ideal EQ curve for the Sennheiser HD6-- series headphones.
A short iFi 4.4mm balanced interconnect is the ideal way to join the two units and it works when they are stacked, as shown in the photos.
CAN Sig. works great with low impedance headphones (its .25 ohm output imp. ensures it will not change frequency response) and its 4 gain levels 0/6/12/18db and big power output provide huge power for planar headphones and almost any headphone available.