Humphrey Espresso Amp Review

AG 222 June 2011

by Doug Young

Low-power boutique amplifiers are common in the electric-guitar world, where the merits of different designs are debated with the same passion that acoustic guitarists devote to the subject of tonewoods. Humphrey Amplifiers is now bringing that trend to acoustic players with its Espresso, an eye-catching, audiophile-quality 15-watt all-tube amplifier designed specifically for acoustic guitarists. All Humphrey amps are hand-built to order in Minnesota by Gerry Humphrey, who has combined his engineering background with inspiration from modern lutherie to give guitarists a unique amplification alternative.

Tubes and Tonewood

The Espresso makes a strong first impression. The small combo amp is covered with dramatically figured hardwood, and its sweeping curved lines make it look far more like an elegant piece of furniture, or even modern art, than a guitar amp. Our review model is made from lightly spalted poplar, but Humphrey will build the Espresso from a variety of woods and can even incorporate inlay and binding to match or complement your guitar. With a hand-rubbed oil finish and dovetail joints, the amplifier would look right at home in a living room beside fine furniture or, of course, a high-end guitar.

The organic look of the wood cabinet is interrupted only by the glow of a row of tubes behind a glass panel and a stainless-steel plate that contains a single 1/4-inch input and a bank of controls, arranged to emphasize the curves of the cabinet. The Espresso’s feature set is minimal, with a gain control for setting input sensitivity; volume; and bass, mid, and treble tone controls. A switch engages the horn tweeter, and another switch activates a treble boost. The amplifier’s back panel is completely sealed and offers only a power plug and on/off switch, and an optional, unbalanced 1/4-inch line out.

A note on the sealed-wood back panel indicates that it should not be opened; there are no serviceable parts, but Humphrey says that capable users can change their own tubes, if necessary, because this is not really a safety concern. I couldn’t resist a peek inside, and removing the panel revealed a very clean layout and neat handwiring. Humphrey uses Teflon-insulated, silver-coated wire and even, high-silver-content solder throughout. Interestingly, even with the back opened, the tubes were not easily accessible.

Clean and Simple Hi-Fi Tones

Part of the mystique of tubes is their sound, of course. With electric-guitar amps, it’s mostly about distortion, but tubes are also a key part of the pristine sound of audiophile-quality stereo systems. The Humphrey fits into the latter category. I found the Espresso’s sound to be warm, transparent, and musical. Playing an acoustic guitar through an amplifier can sometimes be unsatisfying; it’s easy to lose the nuances we hear when playing acoustically. In comparison, playing through the Espresso is fun, and getting a satisfying, expressive tone is all but effortless. I tried a variety of pickups, including an L.R. Baggs Anthem (undersaddle plus mic), a Fishman Rare Earth magnetic pickup, and a K and K soundboard transducer, and the Espresso produced a uniformly excellent sound with all three. The tone was smooth and clear and the amplifier seemed to enhance the tone of the pickups in a very pleasing way, bringing out the best characteristics of each.

The Espresso’s simple tone controls are effective for making broad adjustments but do not support drastic changes. The midrange control offers the most noticeable tonal effect, but the bass control seems to have substantial impact only in the upper 25 percent of its range. The tweeter switch provides one of the most noticeable effects, adding a high-end sheen that makes it easier to get a shimmering rhythm guitar sound and gives definition to fingerstyle and flatpicking tones. Without the tweeter, the amp has a rounder, darker tone that is equally pleasant, but probably most suitable for soft fingerstyle or jazz. The Espresso has no provision for effects, not even reverb, although the direct sound was so rich, I never felt the need for reverb.

With 15 watts of clean power, the Espresso is certainly not a loud amplifier. With most guitars, I was able to play in my living room with both the gain and volume most of the way up without feedback or uncomfortable loudness. The amplifier appears to have some extra headroom in the input gain stage, and I got substantially more clean volume by adding a preamp (an L.R. Baggs Venue DI) in front of the amp. The Espresso would handle some quiet coffeehouse gigs by itself, but it would be necessary to use the line out to feed the sound to a PA system for larger or noisier venues. However, guitarists may be reluctant to take the Espresso to most gigs: the canvas cover offers minimal protection for the fine wood cabinet, and the amp is surprisingly heavy for its size, which, along with the design of the leather handle, makes it somewhat awkward to carry.

Audiophile Acoustic Amplification

With its good looks and impressive sound, as well as an undeniable cool factor, the Espresso is very appealing and fun to play through. Humphrey set out to build an acoustic amplifier that doesn’t look out of place in a living room, and the Espresso succeeds on that front very well. Many will find the Espresso’s minimalist feature set a bit too basic for gigs, and its great looks probably work against it as a gigging workhorse. But if you are looking for audiophile-quality amplification for your home and studio or to add a touch of class to a low-volume gig, the Espresso is an elegant and great-sounding choice.

SPECS: 15-watt all-tube amp. Twin EL84 push-pull design. Single channel. One 1/4-inch input. Gain, volume, bass, mid, and treble controls. Bright switch. Ten-inch Eminence baffled speaker with switchable horn tweeter. 600-ohm line out. Tilted hardwood cabinet, with optional wood choices. 20 inches wide, 16 inches tall, 9 inches deep. 36 lb. Canvas amp cover. Made in USA.

PRICE: $2,495 direct.

MAKER: Humphrey Amplifiers: (612) 770-5012; humphreyamps.com.

Excerpted from Acoustic Guitar June 2011

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