Retail price of review component: $1695


Associated Equipment

Power cord: Signal Cable Silver Res Reference

Sources: Arcam FMJ CD33 and Ayre CX-7e

Interconnects: Signal Cable Silver Res Analog w/ Eichmann silver bullets

Comparison amps: HeadAmp Gilmore Lite v2, Singlepower Square Wave, and empirically with Singlepower Extreme (previously owned) and Cayin HA-1A (out on loan)

Headphones: AKG K701 w/ Equinox re-cable; Grado GS1000, RS1, and HF-1; Sennheiser HD650


Evaluation CDs

Alison Krauss - Lonely Runs Both Ways & Forget About It

Howard Shore - The Lord of the Rings: The Return of the King [OST

KT Tunstall - Eye To The Telescope

Massive Attack - Blue Lines

Norah Jones - Not Too Late

Porcupine Tree - In Absentia

Renee Fleming - Thais (Massenet, 1894)

Sarah Brightman - La Luna

The Crystal Method - Vegas


About the EarMax Anniversary

As might be inferred from its name, the EarMax Anniversary is just one in a line-up of tubed headphone amps bearing the EarMax name. There are four EarMax amps in the line-up, which consists of the standard EarMax, the Pro, the Silver, and of course, the Anniversary. All four versions share the same basic physical design - an approximate 3.5" square base, on which 3 tubes are installed, and then partially protected with a wireframe "cage" over each tube. At 3.5" square, the EarMax amps are certainly one of the smallest headphone amps in the world regardless of the fact that they run with a complement of vacuum tubes. While they're not the smallest tube amps in the world (there are a couple of tube amps even smaller than the EarMax), they're in rare company indeed, to be as small as they are. Tube headphone amps are usually large and heavy, they have to be in order to handle the build-up of heat that tubes inevitably create, so to see one at this size is truly remarkable

Each of the EarMax amps are individually tuned for certain types of headphones and have appropriately varying output levels, but common to all four is an OTL Class A Triode design, an approach which lends itself well towards driving efficient headphones. Indeed, the four EarMax amps are probably best used with efficient low-impedance headphones like those from Grado and Audio-Technica, but it's primarily the Pro that's been designed with low-impedance headphones in mind with its 35 mW per channel output - the Silver and Anniversary have 50 mW per channel output, and the standard EarMax has 100 mW per channel output, for them to better handle higher-impedance headphones.

Unique to the EarMax Anniversary specifically is a larger power supply unit over the standard and Pro, upgraded internal components, gold-plated parts including the RCA jacks, and a 4-conductor power supply cable. Its tube complement is one NOS 12AT7 and two NOS 6922. And finally, it's called the Anniversary as it celebrated the 10th year of the EarMax line upon its release in 2005, and as part of that celebration it received a gold color theme, a deluxe metal "bombproof" style carrying case, along with a very, very limited release - only 100 pieces made for the world-wide market, just 33 of those for North America! A collector's item for sure. With a status like that, is $1695 for the Anniversary worth it?


Headphone-Specific Pairings

Since the EarMax amps are known to be tuned with Grado headphones, I took the Anniversary to task with the Grado GS1000, RS1, and the HF-1 (a very limited edition headphone made specifically for the headphone users at


The pairing with the GS1000 was an interesting one. It was synergistic on only a few levels - it subdued the treble refinement of the headphones and made it sound grainy instead, but on the other hand it did add weight and a sense of being more corporeal. There was greater depth to the bass, and in fact came across as a bit boomy. Almost subwoofer-like tonality, but not quite all the way there. Correspondingly, there seemed to be more force and push to the mid-bass coming from within the instruments, particularly noticeable on the Alison Krauss' CDs. The acoustic bass sweltered that much more, with more tactility and power. Music overall simply sounded more dynamic as well, with a strong force on drum and other percussion impacts for a harder, more engaging sound.

With the RS1, the Anniversary seemed to fare much better. Mid-range was smoother on it, with a gentle, almost relaxing quality, yet very creamy at the same time, as if the instruments wanted to condense and coalesce for a build-up. Yet, at the same time, the amp seemed to counter this by splitting the layers apart for a multi-layered feel not too dissimilar from what AKG's K701 intrinsically does. There was more audible mid-range detail as a result, especially in the area of vocals. From Alison Krauss to Norah Jones to the male voices of Porcupine Tree, all sounded more multi-faceted and more dimensional to make it sound like an actual human was behind the words, not just them coming from somewhere. Also lots of palpable texture on guitars and a more noticeable inner push on Alison Krauss' voice, as if it was enhancing the mid-bass and lower mids, but not too much to offset frequency balance - merely just enough to balance out the response of the headphones.

The pairing made everything sound more subtle, with a sweeter emotive power, and ultimately very soothing - though the amp did seem to have a very noticeable tendency of smoothing out attack that it made everything sound a bit slow. On the plus side the amp did hold onto decays amazingly well, possibly the best I've heard from an amp yet - it brought out note decays full and long, no matter the sound, whether cymbal wahs or a guitar note lingering in air or a singer's final gasp for breath. So an imparted slowness in attack, but excellent decay.

The HF-1 was probably the worst pairing though, the amp just didn't seem like a good match for it. Dynamics were too restrained on it, and there wasn't enough treble - the amp didn't seem to offer any treble refinement of its own and the HF-1 is a mid-range focused Grado as well (conversely to other Grados that have bright treble). The pairing simply lost a good amount of detail.

The amp's gain worked extremely well with these 32 Ohm Grados, low enough to achieve any desirable fine-tuning. In fact, the volume knob had to be turned up considerably high to get these Grados to loud levels, and the amp always had a silent background as well, so it can very well be used with even lower-impedance headphones should the need arise. But the most amazing pairing by far was with the Sennheiser HD650, a notoriously high-impedance headphone at 300 Ohms. This rating apparently meant nothing to the amp though, as it delivered a surprising amount of control and power over the HD650, more than I thought was possible. All music gained a huge amount of tactile realism, so much that drums (whether kick drums, timpani, or kettle drums), acoustic bass, and all other possible mid-bass instruments didn't just exist, it was as if every one of them became a veritable punching ball. In the same way that a boxer delivers a hard, focused, crunching blow, the amp delivered the most realistic, out-of-head experience I've heard yet. Impacts didn't just land, and acoustic bass didn't just play either - the amp coalesced these elements to give them not just weight, not just dynamics, and especially not just impact either. There was actual mass and density behind them, at the level of feeling as if an object was actually moving through space to hit another, in the case of the drums. And in the case of acoustic bass, the amp seemed to add so much controlled mid-bass energy that every note felt like a boxer's punch - a huge impact, but no flab, just lots of clean force. And it doesn't stop there either - the amp also deepened out the bass to give the entire spectrum even more bass emphasis than what the HD650 already has, for those who like it. Could be a little too much for those who prefer to have more mid-range and treble, but for those who like bass, the Anniversary would clearly be up their alley. Truly dynamic-sounding, and always powerful - simply an enhancement of the HD650's qualities.



Frequency Response

To get a better idea of the amp's natural frequency response, I paired it up with the AKG K701, always ideal as a reference monitor for any other component. Interestingly I found the amp to not have much synergy with this headphone, strange considering that the K701 often benefits from tube amps.


In this pairing I discovered that the Anniversary wasn't all that stereotypically "tubey" sounding, probably the reason it didn't fare as well here with the K701. It barely added any real emphasis to the mid-range and instead rounded out some other edges of the sonic image - specifically treble, layering, and soundstage. Consistent across all headphones including the K701, the Anniversary didn't offer anything in the area of treble, and in fact downright detracted from it. Leading edges got dulled and lost bite, and there was no shimmer or sparkle. Violins never really sang on it and cymbal strikes always sounded incomplete too.


The main strength of the amp was in the mid-range, not in filling it out per se, but rather smoothing out its imaging, spacing out the layers to prevent them from sounding like a congested mix and less forward, and more 3D. On the flip side, it reduced the size of the soundstage though and sliced out a good chunk of the K701's ambient air. That might be a good thing for those who prefer a smaller, more intimate stage, but that remains a detraction nonetheless. The amp also seemed to give the K701 the same extra bass punch heard on the HD650, which is good and something that the K701 can use more of, but it took away from the attack here too, causing a slight lack of timing. It did help fill out some of the K701's short decay though.







$1695 for an extremely limited-edition amp isn't that bad of a deal, especially for something as small as this, but as with all amps, nothing is perfect, and the EarMax Anniversary does have a few holes in its lining. It's attractively small, and it does have a fine sound, but ultimately this seems like a piece that primarily amp collectors would find worthwhile. The EarMax and EarMax Pro look like far better options in the EarMax line due to their more affordable prices and higher availability.