HeadAmp GS-X mk2

True, from "Those Wonderful Folks That Brought You the Blue Hawaii"…

…except, subtract the tubes, use different designers, develop for dynamic headphones, use bipolar transistors output in class A, have a much more extended frequency response, undergo extensive modification including new exquisite volume control, produce up to 6 watts into a pair of headphones, and more. However, the Blue Hawaii and GS-X mk2 do share two important aspects which do relate.

Fanatical attention to build quality and parts use (and made in Virginia!).
Demonstrate extremely high musical taste levels. This works for me!

Specifications for the HeadAmp GS-X mk2:

Type input/output: Low noise quad JFET input; Pure Class A bipolar transistor output
Frequency Response: 10Hz-90kHz +/-0.2dB
THD+N: 0.0008% @ 1kHz/0dBu
Crosstalk Gain: L – 1X, M – 12.5X, H – 21.5X
Input Impedance: 50k ohm
Output Impedance: <0.5 ohm
Dual mono balanced headphone amplifier + preamplifier originally designed by Kevin Gilmore, and updated by Justin Wilson of HeadAmp.

I know I should not do this and rephrase HeadAmp's prose into something unrecognizable, but this was so tightly written and accurate as far as I can tell on my 15 pairs of reference headphones, it is best just quoted:

From HeadAmp:

"The GS-X Mk2 is HeadAmp’s flagship amplifier for dynamic and planar magnetic headphones. With a circuit that has evolved and matured over a 15-year period, the GS-X Mk2 is the most powerful, linear, and transparent amplifier that we have ever produced. Pushing up to 6W of class-A power into balanced headphones, the GS-X Mk2 can tame the toughest headphone loads on the market, while its’ low-noise circuitry delivers an equally brilliant performance with sensitive in-ear monitors.

In addition, the GS-X Mk2 makes a fine preamp for your stereo speaker system. With its’ high input impedance, low output impedance, multiple I/O options, 3-way gain control, and precise volume control, the GS-X Mk2 can fit into almost any stereo rig, and provide the same wonderfully transparent sound output that it does with headphones.

The GS-X Mk2 is a carefully handcrafted piece of audio equipment, with painstakingly matched components, and the highest standards for build quality in the business. Every GS-X Mk2 is tested extensively throughout the build process, as well as before, and after an extensive burn-in process to ensure the best possible performance.

As 0f January, 2017, all GS-X Mk2 ship with the DACT 24-step attenuator volume control."

Reference System

Headphones (all with 6.5mm plugs):

Mr Speakers ETHER Flow
ESS 252
ESS 422H AMT
Grado GS 2000e
Grado LA&OC Audio Society 25th Anniversary Edition
Grado RS1
Grado RS1e
Grado PS1000e
Grado PS2000e
Grado Special Maple Wood Limited Edition
Ultrasone Edition 8
Audeze LCD-X with Kimber Axios and UITaudio PMP headphone cable
Audeze EL-8
Astell&Kern Beyer AK T1p

And utilizing the GS-X mk2 as a preamp: The AKG 1000 Earphones powered by an E.A.R. 534 tube amplifier. (Note to Reader: No, you will not have to sit through an analysis of how the GS-X performed with each pair of cans! I had to do it, but you do not.)

My favorite combo with this headphone amp? An audiophile friend brought over the Sennheiser HD 800S. That was seriously good sound. They were a stellar combo and highly recommended.

Reference Headamps

E.A.R. HP4 tube headamp designed by Tim de Paravicini
Grado RA-1 with AC power supply...now discontinued! Designed by Sid Smith
MicroZOTL from Linear Tube Audio designed by David Berning

This puts Gilmore and Wilson in stellar "designer" company.

Cables

UITaudio with PMP Modules as interconnects (https://www.uitaudio.com/)
Kubala-Sosna Emotion interconnects and power cords
Kubala-Sosna Elation! power cords
Kimber Kable PK 10 Palladium power cord for the GS-X mk2 (after trying every AC Cord I own.)

Sources

Townshend Audio Allegri+ passive preamp as source switchbox
ModWright Sony 9000 Universal Disk Player with Mullard tube in PS
E.A.R. Acute 3 Tube CD player
Stein Aventurin V6 phono cartridge, modified Benz LPS
E.A.R. 324 phono stage
H.H. Scott 350 FM stereo tuner
McIntosh MR71 FM stereo tuner
Dynaco FM 3 stereo FM Tuner
Dynaco AF6 AM-FM stereo tuner

Funny story. I was visiting The Source A/V in Torrance, CA, for the World Premier presentation of the MrSpeakers VOCE Electrostatic Headphones being auditioned on a gorgeous Blue Hawaii Headamp. The brilliant Dan Clark was personally presenting them. The Source is the only dealer in America authorized to sell HeadAmp products outside of Virginia. I brought along my trusty pair of Grado PS2000e Headphones to plug in around the store in the dozens of incredible headamps on display. As I listened to the marvelous(!) VOCE, I asked if there was a phone plug I might use to check the Grados. Right there was a very red finished GS-X mk2 with the identical musical source. I plugged in only to hear my Grados come to life like protoplasm was super injected into the drivers. The BIG Grado PS2000e have the biggest drivers ever utilized by Grado, and the ability of the GS-X to make them sit up and take notice with up to 6 watts of power is rather compelling!

This got my attention and I spent the rest of the time trying to find an even tiny sonic problem with the GS-X. After a bit of begging, a unit all broken in and ready to review arrived at the Levi mansion for my audition. Thank you Jason Lord, proprietor of The Source A/V, for encouraging the factory loan.

Getting Ready to Ride

I turned on the GS-X when it arrived, gave it an FM source, and it stayed playing for two weeks while it was auditioned. It got a bit toasty, but not a problem. Solid-state gear likes to stay on, even Class A pieces.

I will say one thing right off: It is power cord sensitive. In fact, it is not supplied with one, so you might choose your favorite. Audition every one you have before you settle in. I usually do not use the Kimber big boy on anything except power amps, but it not only proved smooth as a baby's ass, but let the GS-X bloom like no other cord in stock. Kimber Kable PK 10 Palladium Power Cord increased impact and reduced grain in the GS-X presentation.

Needless to say, choose your interconnects carefully! The GS-X is so very neutral, it shifts musically to the colorations that may be inhabiting your cables. I found only a handful of cables that answered the musical call. They are posted above and, of course, I recommend them to you. I will not tell you what I left out, but they hang in two very large closets.

Performance, Performance, Performance!

In my judgement, the GS-X is the most neutral, most musical, most powerful, most flexible, and most desirable solid-state offering I have heard to date, period. The nuances are as startling as the crescendos with the GS-X. This modern super headamp is truly super, with flaws so truly subtle they may have been imagined. Plus, the Mercedes-like fit and finish gives you ultimate confidence in its long-term performance.

I found the best headphone performance came from the GS-X in the "M" toggle position of overall unity gain. In medium one has the smoothest, most elegant sound from most cans, and the most flexibility from the outstanding volume control. I did not hear any real advantage on headphones that were balanced versus those that were single-ended. Cans maxed out for balanced connection performed well in the balanced outputs. The same can be said for those terminated with a 6.5mm plug.

Now here is a twist. I did not expect the performance of the preamplifier section to be exceptional, and only utilized it when I checked out the performance of the AKG 1000 Ear-speakers. I kept the preamp section off to avoid affecting the headamp performance. Attached balanced to the E.A.R. 534 amplifier, the GS-X provides smooth, detailed, and delicate music. In fact, the preamp section is superior overall with finer nuances and more warmth than the separate headamp. I was quite surprised.

It is a top-notch and flexible preamp, with ultra-low distortion and no noise of any kind. No kidding, I cannot name a sweeter solid-state preamp under $5000 than the GS-X. Add a very fine flexible headamp to the package and you have a winner no matter how you look at it.

I am delighted to see the unit does not include a DAC. So many do, and it is the Achilles heel of expensive gear right now. I want my money to go into bullet-proof performance and intense, involving musicality. I want nothing obsolete in a year. Makes sense to me that a company that produces the amazing Blue Hawaii can build a compelling solid-state piece.

Though the Grado cans with their great efficiency performed well in the GS-X, the less efficient MrSpeakers Ether Flow and the Audeze LCD-X really sing, as well. The power and punch of the GS-X energize their bass and dynamics. The more efficient A&K T1p Beyer cans were set ablaze in musical glory by the GS-X. The new ESS 422H AMT headphones are 110dB efficient and were better performing than expected from this hammer of a headamp. I was not disappointed, though the GS-X was barely on! These are superb musical cans when efficiency is paramount.

The inefficient closed-in sound from the Ultrasone Edition 8 improved with the GS-X. Not my favorite cans, frankly, but the GS-X powered them with the kind of linearity and smoothness I have not encountered. I liked the way they performed, for a change.

Compared to the twice as expensive E.A.R. HP4 headamp, the GS-X quickly demonstrated the differences between excellent solid-state and excellent tube amplification. They do not sound the same, but are both satisfying in their own ways. I need both, as they represent the pinnacle of design in each of solid-state and tube power. $3000 for the GS-X strikes me as a fair sum for such flexibility, sophistication, and elegant industrial design. The red escutcheon is my favorite, by the way, and worth the small added toll!

Quibbles

There were a few.

About the name: HeadAmp GS-X mk2, is a catchy memorable name if you are a super computer. I bet an engineer came up with it. Call me, and I will suggest something that sparks the imagination the way the headamp itself does.

Another thing: There are a total of four half-inch toggle switches on the two units, each recessed a quarter of an inch. That equates to a quarter-inch of switch area that one can reach without claws. Two of them are three-position switches, with micro amounts of travel. One three-way selects over-all output, is used constantly, and is labeled "L" on the bottom, "H" in the middle, and "M" on top. So to go from low to middle output, one has to switch through high to get there? (Ever wondered why reverse is not between 2nd and 3rd gear?) How about getting rid of the recessed toggles and making them flush with the face. That will give you a reasonable half-inch to use. Plus, the order of the three-position switches needs your attention.

Finally, the four single-ended outputs on the back are a bit too close together. Everything else is perfect. Many expensive cables have really big connectors these days, and at $3000 plus $200 for the magnificent red paint job, your prospective buyers likely buy the biggest and the best interconnects. They need more elbow room!

Summary

The HeadAmp GS-X mk2 is a refined piece of high-end workmanship, built to maximize headphone performance and provide excellent preamplifier applications, both balanced and single-ended. It is quite a looker. Endowed with virtually zero distortion, and with up to 6 watts of output, one would expect superb performance with any cans on the planet. You will not be disappointed with the results: Its smoothness and sophisticated sound yields a top listening experience for the long haul. And you can truly rock out with this beast!

The extra added attraction is a leading edge and intensely musical preamplifier provided in the two-box package. Flexible and powerful, the combination with a solid-state or tube amplifier becomes a compelling combo when space is an issue, but performance must not be compromised. The HeadAmp GS-X mk2 is an advanced design hand-built in Virginia in small quantities. It has my strong recommendation.

HeadAmp GS-X mk2

Retail: $3000, $200 extra for special order color

Factory Direct

https://www.headamp.com/order/headamp-gs-x-mk2-balanced-headphone-amplifier/

HeadAmp Contact: Justin Wilson

+1.888.674.3665

[email protected]

www.headamp.com

Sold at a single U.S. dealer

The Source AV Design Group

3035 Kashiwa Street

Torrance, CA 90505