AXPONA 2015: Woo Audio


by Joshua Emmons

If you walk into a room at AXPONA, and it’s noticeably 3–4 degrees warmer than the hallway, you know it’s chock full of really tasty amplifiers. So it is with Woo Audio: headphone amps with cheerfully glowing tubes every which way you look. Some modern. Some unabashedly retro. But all delivering a sonic warmth to match the heat they’re pumping out into Woo’s small space on the Weston’s lower level.


I’m here to listen to the Stax 009 paired with Woo’s WES front-end. It’s a fully balanced OTL that, I’m told, is a several solid steps up from what you’d get from Stax, itself.

No arguments here. This is my first experience with electrostatics and I have to admit I’m rather at a loss for words. The detail present would be mind-blowing if it weren’t so natural. A better adjective might be “transportive”.

Listening to Todd Garfinkle’s exquisite work with his label MA Recordings, for example, I’m hearing classical piano. But I perceive not just a collection of notes woven into a song, but also the squeak of the pedals, the syncopated thump of the hammers. My ears open to the piano as a machine — an instrument set to the work of producing sound — not just the sounds themselves. It is an incredibly holistic experience.

But at easily 2–4 times the cost of a stock Stax amplifier, I’d have to expect the WES would be pretty darn good. Honestly, I fear the craftsmanship on display is wasted on me, a newcomer not really certain what he’s listening for. Regardless, I’m grateful to be afforded the opportunity.

The WA7 Fireflies

The WA7 is a sight to behold. If you think you might be in the market for a headphone amp for your workspace, and you want to impress your coworkers, this is your pick. There’s something about exposed tubes that makes even hardened tech enthusiasts a little weak at the knees. And the Firefly’s clever glass protector does an amazing job of showing them off in their fullest, providing all the protection of a cage without the gothic sensibilities.

So now you’ve got your silky smooth sound, but do you find the warm, rosy glow of two valves under load just isn’t cutting it for you? Why not pair your amp up with the WA7tp, a matching tube-based PSU that duplicates the WA7’s aesthetic down to the tiniest detail? Double your glow, double your fun.

I should also note the WA7 comes in a WA7d flavor that includes a TOSLINK connector in addition to USB. I thought this a little strange until I remembered the growing number of media streaming pucks plugged into my TV (not even counting the video game consoles that can double as media servers). This is a welcome addition that I’d find many uses for.

The Future

Woo’s (as of yet unnamed?) prototype portable DAC/amp combo unit is also out and available for play. If you think portable amp is synonymous with solid-state, Woo is out to change your mind. This is a battery-powered tube amp about the size (and weight) of a brick. Seriously, “portable” in this instance should be thought of in the same light as how the Apple IIc was, technically, portable. It’s not for throwing in your bag during a trip to the mall, but I can imagine compelling use cases around hotel stays, layovers at airports, or even short flights (though FAA regulations may have a thing or two to say about that).

The (still non-finalized) design is classy and elegant. It’s less WA6 and more WA7 filtered through an old Braun transistor radio. It has a pleasingly large pot for volume and, true to Woo fashion, a large glass window showing off its tubes (though I’m told the window may or may not stay depending on concerns over fragility).

And its sounds is lightyears beyond any other portable amp I’ve tried. I’m using it to drive a pair of Audeze LCD-3s, and for my money, it sounds very close to a WA6. The Woo representative very carefully points out several times that this is a prototype model, and that any number of things like the tubes, the battery life (which is currently around 3 hours), or really anything about the amp could change at any time. But were they to ship what they have now, I’d say it’s a winner.


  • WES: $4,990
  • WA7 Fireflies: $999
  • WA7d (optical TOSLINK): $1,199
  • WA7tp (tube power): $399









About Scot Hull 1062 Articles
Scot started all this back in 2009. He is currently the Publisher here at PTA, the Publisher at The Occasional Magazine, and the Executive Producer at The Occasional Podcast. There are way too many words about him over on the Contributors page.