HeadAmp is a Virginia-based company focused exclusively on building portable and desktop headphone amps and amp/DACs. For the past nine years, however, HeadAmp has made a point of offering a series of specialized, limited production electrostatic headphone amplifiers, many of them designed by the famous headphone amplifier guru Kevin Gilmore. HeadAmp’s President Justin Wilson provides this brief history:
“HeadAmp’s first electrostatic amplifier was the KGSS (Kevin Gilmore solid state) introduced in 2003—at least five years before any competitors decided to support electrostatic headphones. The Blue Hawaii was released in 2004, and the greatly upgraded Blue Hawaii SE began shipping in 2009. The KGSS has since been discontinued to focus on meeting the demand for the Blue Hawaii SE.”
Our review subject here is the Blue Hawaii SE (for “Special Edition”, $4995 - $5999, depending on options); it is intended as a no holds barred, state-of-the-art product that complements the firm’s slightly less expensive, but also very ambitious, Aristaeus electrostatic headphone amp ($4495).
While the Blue Hawaii SE has been around for several years, it is only recently that anyone offered an electrostatic headphone good enough to show off the amp’s full performance capabilities. Specifically, we are speaking of Stax’s stunning new SR-009 headphones, which Playback recently reviewed (click here to read the review). As we said in the Stax review, the SR-009 is easily a contender for “best headphone in the world”, so it is good news indeed that several high-end amplifier manufacturers are offering products specifically for the Stax (in addition to HeadAmp, Cavalli Audio, Ray Samuels Audio, Stax, and Woo Audio have—or soon will have—notable electrostatic headphone amplifier offerings).
Of course, the Blue Hawaii SE should work perfectly well with other Stax models like the SR-007 Mk II and with late, lamented electrostatic models from Sennheiser. Given the impressive results we have seen to date from the SR-009, however, that is the headphone we used for evaluating the Blue Hawaii. This is important because, as we will see, the Blue Hawaii SE raises questions about whether it is helpful to think of the amp and headphone as an integrated system more than as individual, universal components.
The Blue Hawaii is a large hybrid amplifier with a separate power supply housed in a smaller matching box. Hybrid in this case means that the amplifier’s early gain stages are solid state, while the output stage is built around tubes (hand-picked, matched quad, “reissued” Mullard EL34’s in the Blue Hawaii SE). We asked Justin Wilson about the topology of the amplifier, and he offered this reply:
“Kevin Gilmore goes into detail on the (amplifier’s) circuitry in his HeadWize article. Apart from technical explanations in this article, Gilmore says his inspiration for the design was the expensive and rare Stax SRM-T2 amplifier which was also solid state with a quad of EL34 tubes. Stax has not had a ‘statement’ amplifier since the SRM-T2.”
The amp is designed in what we would characterize as the minimalist chic style. By this we mean that the styling of the amp is deliberately understated, so that instead of emphasizing dramatic visual details, the amp’s appearance invites viewers to savor the Blue Hawaii’s overall fit and finish quality, which are simply superb (this amp is lovingly handcrafted and looks the part in every way). If you go to HeadAmp’s site, the photos simply do not do justice to the execution of the design. The metalwork and engraving, along with the fit of the parts, is excellent.
Two final aspects of HeadAmp’s approach deserve comment. Unlike some high-end electrostatic headphone amps (e.g., the Woo Audio WES) the Blue Hawaii SE is basically offered in one configuration, with one carefully chosen set of tubes (the aforementioned matched Mullard EL34’s), one power supply, one quality level for all of the other core parts used in the amplifier. As Justin Wilson points out, “the Blue Hawaii SE has no capacitors in the signal path, so there is much less reason to have to upgrade.” Expanding on this point, Wilson adds that,
“The BHSE is available with one upgrade, an Alps RK50 volume control (possibly the best audio potentiometer in the world). Over 70% of buyers choose the upgrade. The standard volume control is a DACT stepped attenuator.”