Disclaimer: I borrowed both Portaphile Micro amps for a recent shoot and decided to review them on my own terms.

Portaphile’s new Micro headphone amp does a Star Trek beam-me-down-Scotty to the excellent audio circuitry (and cool-ass machined logo) found in the Portaphile 627x. The destination? A much smaller, much lighter, pocket-friendly box, that like the Vorzüge PURE II, cuts almost no performance corners. And, at 499$ USD, it costs a full 100 bones less than its big-me-up-Scotty sibling.

Why Micro?

It’s a reasonable beam-me-down, really. Even strapped to an iPod 5G, and huffing through one of Forza Audio’s excellent 30-pin iPod line out cables, the Micro combo weighs 20 grams less than the Portaphile 627x does alone. And, it is both shorter and smaller than its big brother. The only question left is: ‘so, does the Portaphile Micro stand up to 627x performance?’.

With stiflingly few retractable provisos, the answer is a resounding ‘yes’.

The Marque

I’ve followed Portaphile since Dr. Xin, the audio world’s only all-in-one rocket scientist, brain surgeon, men’s speed skating record holder, and inventor of transparent aluminium, dominated the waiting list at Headfi. Well, Dr. Xin went bye bye, but Cesar Aguilera, the human cog behind the Portaphile machine, has kept spinning out amazing amps. And Micro, despite being the brainchild of a Texas resident, is anything but Texas-sized. Thank God.

Portaphile’s new logo is hot. It’s like surfer hot. (I’m a Swedish-born Canadian; I know nothing about surfing, but bear with me as I cast the eyes of my memory over tiny bikinis and lots of sand.) Under the right light, the new logo’s machined edges and grooves look fab. And, their matte contours don’t collect finger prints. I just hope that Cesar will find the time to develop tidy literature to accompany his tidy amps- and, maybe even a box that doesn’t look like something your eggs come in.

The Ins and Outs

In a chassis the size of the Micro, there’s not much room for ergonomic perfection. Case in point: Vorzüge’s PURE II places the ins and outs a little too closely; getting at either the gain or ON/OFF switch can be a bit of a chore. Micro spreads both recessed ports apart, squeezing the gain switch in between the two. The volume pot doubles as an ON/OFF switch. As a result, there is more room to twiddle the gain switch; and fat interconnect cables won’t mash one against the other. The only downside to this design is that you must pinch, not massage, the pot to get it going.

The Chassis

The mini-USB charging port burrows into the back of the Micro. And before you ask, no, Micro is not a DAC. To myriad computer peripherals, the mini USB form factor is ubiquitous. It is great to have on a portable amp. Being able to lean on a single 5V USB charger for your phone, your iPad, and your amp is a blessing, especially if you spend any amount of time in hotels or in airplanes.

Because Micro sports a USB port, you may be tempted to leave it plugged into your computer whilst listening to music. I’ve found that doing so raises the noise floor considerably. Best performance comes by running the amp from its internal battery, and barring that, from the mains.

Fastening hardware fit into deep countersunk niches as do the IN/OUT and gain switches. Even the volume pot twirls in a small shallow of its own. The USB charging port sports a synthetic sleeve to protect it from grinding against the case. Presumably, it also insulates the port against poorly regulated USB power supplies and cables.

The only unclever thing I see in the Micro is its employment of different-sized restraining bolts in the volume pot and chassis. The pot responds to a H1,5-sized driver, while the chassis bolts have a thing for a H2,0 driver. That silly catch aside, the design is solid, if not overly polished. Shaken violently, it gives up nary a rattle. Dropped, it punches a hole in your plastic Japanese flooring.

The Choice

Unfortunately, Cesar gives you a choice. Do you want the OPA627 (regular) version, or do you want the Muses version? I’ve been asked countless times by pretty cool headfiers and pretty cool HFNers and pretty cool Ωers, which is best. The answer isn’t exactly clear-cut- that is, unless you’re all about performance by the numbers.

I have spent weeks with both amps. Sadly, tomorrow both must return to Cesar. But before they do, I want to parade my convictions about. The results of all the listening I’ve done, and from rather hefty hardware testing favours the OPA627 version, but that doesn’t mean it will sound better to you. It simply trumps the MUSES in every significant benchmark, whether driving low, high, or medium Ω loads.

The MUSES version isn’t able to sustain the same strong signal into the usually benign Beyerdynamic DT880 600Ω, or Audio Technica ES10. But when driving earphones of any flavour and spec, MUSES picks things back up. In all instances, the regular OPA627 version simply sings.

Sound impressions on the next page

5 / 5 ( 3 votes )