Disclaimer: MyST kindly loaned both units for the past several months. This review is way overdue. PortAMP II goes for 850$ USD and PortaDAC 1704 goes for 1100$ USD. For more about PortAMP II check the following link: MyST PortAMPII. For more about the PortaDAC 1704 check the following link: MyST PortaDAC 1704.
Performance-minded users looking for a one-size-fits all amp need look no further than PortAMP II. NOS heads looking for a calm, mindful listen and out-the-wazzo inputs need look no further than the PortaDAC 1704 (herein 1704). Both utilise the same oblong case, the same power nipple, and the same mains adapter. In my opinion, their killer feature is a robust battery.
It is incredible just how powerful PortAMP II is despite being battery powered. It is the most powerful battery-powered amp I’ve used. In fact, it powers my DT880/600 and MyST’s own OrtoPhones far better than the Lynx HILO, and with more power than Linear Tube Audio’s MZ2-S. All that power. Mains agnostic. Which makes silly PortAMP II’s dual, concurrent 3,5 stereo outputs. It’s not a good-looking amp. There’s no way that second output will attract the fairer sex. Which raises the question: why not a single 6,3mm jack?
Despite their length, neither unit flexes under even my squeeziest grip. Each face and ass is anchored by four bolts per side, and helical locks turtle-necking the stereo ins and outs. The 1704’s RCAs are ready for nuclear winter. Each unit’s power button depresses with a bit of work, but is buffered so well that even through the most sensitive earphones, you won’t hear any ON/OFF pop. Cheap but sturdy rubber feet are pasted below each corner. They’re clear, so they won’t mark wood tables or desks.
PortAMP II’s matte picks up fingerprints and other marks easily, the shiny 1704 does not. Not that it would matter. Both look like enthusiastic garage projects. They’re just way better built than any garage project I’ve touched. And that power button, as meh as it is to depress, is so damn solid, and so damn easy on the ears.
Both units’s garage day aesthetics bely their boutique prices. At least all of PortAMP II’s labels are milled into the chassis. 1704’s on the other hand, are laser printed.
The 1704 offers more inputs than typical, a great NOS chip, and both stereo 3,5mm and RCA outputs. I’ve just brought it up from my living room, where it remained connected to an Apple TV (3) via a HDMI splitter. Its RCAs fed directly into a BeoLab 6000 powered speaker set, whose volume, tracking, etc., were controlled by my iPhone SE.
PortaAMP II’s sound after the jump: