August 2010

ASR Emitter I Integrated Amplifier

Associated Equipment

Speakers -- Wilson Audio Specialties Sophia, Audioengine A2

Integrated amplifier -- Jeff Rowland Design Group Concentra

Sources -- Wadia 830 CD player, Logitech Transporter, Apple MacBook, Devilsound USB DAC

Interconnects -- Cardas Audio Neutral Reference

Speaker cables -- Cardas Audio Neutral Reference

Headphones system -- Sennheiser HD 600 with Cardas headphone cable upgrade, Ultimate Ears UE 11 Pro, Ray Samuels Audio Emmeline The Predator

Accessories -- Audio Power Industries Power Pack II, Cardas Audio Signature XLR, RCA and BNC caps

Reviewers' Choice LogoIím no slave to dogma, but Iíve clung to a few personal truths about home audio that Iíve been unabashed to share with anyone whoís bothered to ask. No. 1 is that the bulk of an audio budget should go to the loudspeakers, in the belief that they make the single largest contribution to the overall sound of a system, and that the rest of the money should be spent on the source and amplification components. Recently, however, Truth No. 1 was upended. 

ASR Audiosysteme, founded in 1980 by Friedrich Schaefer, is a German maker of electronics with the stated goals of ďreproducing music as a complete experienceĒ by combining ďthe harmony and musical sound of tubes with the accuracy and sovereign power distribution of modern transistor amplifiers.Ē ASR manufactures phono preamplifiers, but their best-known products are the Emitter I and Emitter II. Although both are integrated amps, ASR designed each as a power amp with a gain stage and volume control, for the purest signal path possible. The Emitter I has been in production for 30 years, during which time its circuit design and parts content have been continually refined and updated. That apparent total confidence in the design and implementation of the product is one way to explain why these amps are so rarely available secondhand.  


The ASR Emitter I ($10,950 USD as reviewed) is a solid-state, MOSFET-equipped integrated amplifier with a separate power supply that connects via a hefty 2.0m umbilicus. The Emitter I is also equipped with its own heavy-gauge AC cord, though ASR warns that this not be replaced with an aftermarket cord, and that the power supply should be plugged directly into the wall outlet instead of a power conditioner. Because ASR believes that metal is too resonant to be used in casework and can adversely affect the signal, much of the Emitter I (except for those parts that must be made from other metals) is enclosed in acrylic. 

From an aesthetic standpoint, Iíve never been a fan of the use of acrylic in stereo gear, but the Emitter I is beautiful -- photos really donít do it justice. ASRís rather dated-looking logo aside, the amp is gorgeous; the visible glow of the LEDs on the internal circuit boards elicited positive comments from everyone who saw them. The Emitter I is available with casework of clear or black acrylic. Both are beautiful; Iíd have a hard time choosing between them. Thereís also the Emitter I Version Blue, an $850 upgrade (cosmetics only) in which the front LEDs are blue, the heatsinks can be specified as black or silver, and the brass feet are chrome. 

The main amp measures 16"W x 7"H x 16"D and weighs 42 pounds. The standalone power supply, which contains two 500VA transformers and provides a whopping 406,440ĶF of capacitance, measures 18"W x 6.3"H x 12.5"D and weighs a hefty 68 pounds, despite being smaller overall. The Emitter I is claimed to output 140Wpc into 8 ohms or 250Wpc into 4 ohms, so it should have no trouble powering most speakers. The frequency response is stated as 1Hz-100kHz, +/-1dB, and 20Hz-20kHz, +/-0.2dB, with a maximum distortion of 0.01% and a damping factor of over 600. While my review sample came with the standard AC power supply, a battery power supply is available as an option.  

Each side panel of the main amplifier is a massive heatsink. Despite my long listening sessions, sometimes at high volume, these sinks never became uncomfortably hot to the touch. On the front panel is a central volume control knob of polished chrome that is silky-smooth in action, with a feel that reminded me of a fine Swiss watch. Below this is a LED display that indicates the volume level, in digits large and bright enough to be seen from across a big room. Flanking the volume control are two more polished knobs, the left for Power/Standby and the right for Source selection.  

At the center of the rear panel is a fixed umbilicus whose other end attaches to the rear of the power supply with a massive clamp. Flanking that are pairs of hefty speaker binding posts. These can be hand-tightened; they tightly gripped the spade lugs of my speaker cables. The top of the rear panel can include a pair of balanced XLR inputs (a $400 option); below these are six pairs of RCA inputs and one pair of RCA outputs. These are standard, high-quality, Teflon-insulated jacks; better copper or silver WBT models are offered as an upgrade. Supplied with the Emitter I is a small Corian remote that controls the volume, input selection, and mute, and comfortably fit my palm.


If, like mine, your listening room is not on the ground floor, youíll find it best to uncrate the Emitter I and its power supply at ground level anyway -- the size and weight of the shipping containers make them unwieldy. Even so, great care must be taken; this fairly compact amp and power supply -- especially the latter -- are surprisingly heavy. Once Iíd unboxed both components, I wrestled them into place on the floor on opposite sides of my component stand, and proceeded to connect the umbilicus from the power supply to the amp, then hook up my sources and speakers. Only then did I plug in the power supply. Set up was pretty straightforward; I barely consulted the ownerís manual. 

As usual, I began by playing music in the background to let the amp warm up while I did something else (reading the ownerís manual or a magazine, surfing the Internet). After a decent interval, I set out to evaluate the Emitter Iís sound. 

Surprise, surprise, surprise . . . 

After firing up the Emitter I, my first thought was Hmmm, this is one cool-sounding amp -- not cold, hard, or analytical, but definitely not what Iíd expected. At first, I assumed that the amp needed to be broken in, but this characteristic persisted even after extended listening over several days. However, this impression of coolness was dispelled when it dawned on me that what I was hearing was not a cool-sounding amp, but the complete absence of any sonic artifacts that would otherwise obscure the sound. My second thought was Now this is high-resolution sound. Thatís how profound a difference the Emitter I made with my system.  

Transparent doesnít begin to describe the sound of the Emitter I; it was as if a window on the recording venue had opened, to reveal sonic images that were almost tactile. These images were not hyperrealistic, as if etched with lasers, but were fully formed, holographic, and organic. I dislike the characterization sonic bloom, but thatís exactly what I heard -- the music opened up in a way I had never before experienced. Rather than present the music as beautifully reproduced sound, the Emitter I did more to re-create what sounded like a live event than any other component Iíve heard.  

The soundstaging was outstanding. The Emitter I projected a wider and, more important, deeper soundstage that really brought to life recordings of unamplified instruments. I love ECM recordings for their rich warmth and lush, natural tone; the first track I played was ďBlessed Feet,Ē from the Tord Gustavsen Trioís Being There (CD, ECM 2017). It begins with a quiet backbeat from the drums, followed by piano and bass together, with slight variations on pianist Gustavsenís gorgeous melody. As Gustavsen plays, letting the melody develop and progress, I was amazed that this studio recording could come so close to the sound and feel of a live performance. My main complaint with studio recordings is that the reverb used to add space and body often results in a feeling of artifice. The Emitter I went a long way toward eliminating this with its reproduction of the soundstage and by ameliorating the artificial effect of the reverb, which allowed for a natural-sounding decay that was especially notable at the end of the track. All I can say is, Wow! 

The Emitter Iís transparency meant that there was no grit or grain in the treble, and the highs were light and airy, notes floating in the space defined by the soundstage. In the recording of Beethovenís Symphony No.6 with Claudio Abbado conducting the Berlin Philharmonic (CD, Deutsche Grammophon 469-003 2), the Emitter I displayed a delicate touch with the smooth textures of the violins, while still allowing for heft, as needed, down below. And as far as Iím concerned, in the midrange the Emitter I has no peer. The tonally uncolored ASR let the midrange flow from my speakers unfiltered in a most neutral manner, without adding any unneeded warmth or glow. On the title track of Shelby Lynneís Just a Little Loviní (CD, Lost Highway 1744825), she often sounds as if sheís singing too close to the mike -- her voice sounds overripe, tonally too rich. Through the Emitter I, Lynne seemed to take a step back from the mike, while still conveying the songís immediacy and emotional texture. 

With the exception of the low end, Iíve described all of the individual characteristics of the Emitter I, but no track better illustrated how this amp stitched everything together into one cohesive whole than ďDark Star,Ē from the Grateful Deadís Nightfall of Diamonds (CD, Grateful Dead GDCD4081). I may be a heretic among Deadheads for preferring this version of this iconic track, but in addition to an otherworldly performance, itís a sonic delight. Through the Emitter I, all of the textures and soundscapes that the late-era Dead (this show was taped in 1989) was capable of creating were there in all their glory, along with the low-end weight and impact of Phil Leshís bass and Brent Mydlandís synthesizers. Awesome-sounding stuff! And although Iíve heard tighter bass control with one other amp (see below), the Emitter I was only a smidgen less firm while being just as tuneful, and still able to keep a firm grip on the low end. 

ďDark StarĒ was also useful in highlighting the Emitter Iís dynamic performance. I could turn up the volume to very high levels with no sense of strain; the more I turned up the power, the more the music opened up to reveal layers and layers of sound. I reveled in that sound -- it was as if waves of music were washing over me.

Clash of the Titans 

Like the Luxman L-509u ($10,000) and the Esoteric A-100 ($19,000) integrated amplifiers, both of which Iíve reviewed, the ASR Emitter I is in a class that so far exceeds the performance of my Jeff Rowland Design Group Concentra integrated ($5600, when available) that any comparison to the latter would be unfair to both. However, sonic and financial comparisons of the Emitter I with the L509-u and A-100 are certainly fair. 

All three amps are very quiet, with extraordinary dynamic range that seems to exceed their stated power outputs, especially the Esoteric A-100. The A-100 was most like the Emitter I in terms of dynamic range and overall headroom, but seemed a little softer in the treble, with a bit more midrange warmth that was likely the result of its tube-based circuitry. As noted above, only one other amp in my experience has had tighter bass control than the Emitter I, and that is the Luxman L509u, which has bass to die for. But while both of these amps compared favorably with the Emitter I, and had individual characteristics that equaled or bettered the ASRís, the Emitter I was simply more transparent, more cohesive, and a better all-around performer. I could easily live with any of the three, and until now the L-509u has been my favorite. But if I now had to choose only one, it would have to be the ASR Emitter I. 


The Emitter I is a fantastic product thatís so close to the audiophile ideal of a straight wire with gain that itís hard to believe thatís true without hearing it for yourself. In earlier reviews Iíve tried hard to avoid hyperbole, and in writing this one Iíve had to try even harder. When the importer told me to guess the Emitter Iís price, I figured it was close to $20,000. I was astounded to learn that the base price is $10,000: Although by no means inexpensive, the Emitter I costs the same as the Luxman L509-u and only half as much as the Esoteric A-100, but comes with its own separate power supply, jewel-like build quality, and excellent sound -- all of which makes it the much better value. 

I mentioned at the beginning of this review that I used to believe that the bulk of an audio budget should be allocated to the speakers. After hearing the ASR, I now believe that, in this case, Iíd give equal weight to the speakers and the Emitter I and spend far less on a digital source, confident that any compromise in sound quality would be little to nonexistent. Some ďtruthsĒ are meant to be shattered, and Iím happy to chuck this one in the dustbin. The only thing Iím not happy about is sending back the Emitter I. God, Iím gonna miss it.

. . . Uday Reddy

ASR Emitter I Integrated Amplifier
Price: $10,950 USD as reviewed.
Warranty: Two years parts and labor.

ASR Audiosysteme
Hohe Strasse 700, Haus 5A
Herborn D-35745


Phone: +49 (27 72) 4 29 05
Fax: +49 (27 72) 4 04 88


North American distributor:
Musical Sounds, LLC

Phone: (203) 877-7776