November 2011

World Premiere!
Edge 10.2 Power Amplifier
The best sounding solid-state amp that has ever been in my system.
Review By Tom Lyle

  I've been involved in this audiophile pursuit long enough to remember an era when solid-state power amplifiers were judged solely on their specifications. At that time it was widely accepted that one should consider purchasing an amp with as much power as one could afford, but not before reading up on the product's specs -- since one isn't going to hear much difference between amps that have the same power rating if they both have decent and similar specifications. When I began to power my system with transistors rather than tubes in the late 1980s/early 1990s I heard this hogwash so many times I started believing it myself. Another reason I started believing this was that even though some of the differences made one amp preferable to another, these differences weren't huge as long as the power rating was the same. This remained true, at least in my system, that is, until I heard what could be done with a circuit in a power amplifier designed and manufactured with no cost restraints, or at least less restraints than with the more affordable species of solid-state power amplifiers that I was accustomed to. My power amplifier epiphany, of sorts, arrived via a Krell, but I'm sure that it could have happened with another brand of equipment with the same aspirations (and talented designers). Things have never been the same ever since. Of course throughout the years things have sonically gotten even better, and (spoiler alert) this has reached a pinnacle with the state-of-the-art design that is the 225 Watts per channel Edge NL 10.2. I will humbly recount the best I can the experiences I've had over the past 60 or so days living with this amplifier.

I guess that it is more than a coincidence that Edge was founded in 1987, more or less the same time I "discovered" that there was more to an amp than proclaimed by the large audio retailers and mainstream audio magazines. With its base just outside of Chicago, Edge was purchased in 2001 by RB Manufacturing and Electronics, but the site that makes the Edge gear still employs about 12 people dedicated to designing and making Edge's top-flight preamplifiers and preamplifiers.

Bulk
The NL series boasts up to 16 low-leakage snap lock 10k microfarad caps per channel.  The bulk of the NL 10.2's over 100 pound shipping weight is likely due to its transformers, which are "low-leakage/low-field" medical grade type units that are contained within magnetic stainless-steel enclosures that ensure that they are not only non-inductive, but that their performance is also low noise. As I used the Edge website for the lowdown in regards  to technical info regarding the NL 10.2, I later learned that the website may not be entirely up to date, and since learned that Edge no longer uses their Optical Bias Circuitry in their NL series. This used a very tiny (630 nanometer) laser wavelength in each channel's circuit to operate directly on the silicon substrate of the bias transistor. As per Edge's chief engineer Matt Mallett: "The lasers were removed from the circuit due to the premium components rendering the additional responsiveness attributed to the laser in the bias as unnecessary", and he continued that "premium low-ESR filter capacitors are used in all of the power supply circuits to lower power supply impedance to increase the responsiveness, speed and accuracy that our customers have come to expect from our premium gear."

The NL 10.2 is housed in 0.5" thick aluminum which is secured with marine-grade stainless steel machine screws. The NL 10.2's heat sinks are machined from bar stock as the same type of aluminum as the cabinet which enables the amp to operate without the use of cooling fans. Other than what I just shard above there isn't  much other technical information regarding Edges amps on their website, which is odd given the outstanding performance of this amplifier. I guess they let the sound of the amps speak for themselves, which after hearing this amp perform in my system I can't imagine anyone disagreeing with their approach. And if someone has the chance to audition this amp at an Edge dealer, I doubt they will, either.

Current
The 10.2 draws quite a bit of current from the wall. I can't imagine any prospective owner of this amp not using a dedicated line to power the the amp, as I couldn't imagine any Edge dealer not recommending that one be installed if it is not already present in a listening room in which they plan to install this amplifier. The NL 10.2 draws so much current that it is fitted with an input for a 20-amp power cable. The 10.2 had a stock cable in its carton, but it was strongly suggested to me that an aftermarket power cable would make a marked improvement in the sound of this Edge amp, and since I did not have any 20-amp power cables of my own I contacted Cardas Audio. They graciously loaned me a 2 meter stretch of their Golden Reference power cord with 20-amp connectors on either end. The improvement in sound over the stock cable was not at all difficult to hear. The Edge NL 10.2 deserves the best cables one can afford, and the Golden Reference definitely was well suited for the job.

Edge outfits their line of amps and preamps with unbalanced RCA jacks owing to the fact that they are not balanced circuits, because of this and other reasons Edge feels strongly that they sound better with unbalanced inputs and outputs. My sample of the NL 10.2 did have balanced XLR inputs along with the standard RCA, but as I assumed that many if not all Edge amps are going to be used with a matching Edge preamplifier. I only used the RCA inputs on the amp throughout the review. And although I used a tubed Balanced Audio Technology (BAT) preamplifier for much of the review using its RCA outputs, I also used Edge's own G2 preamplifier for a time. I decided not include my thoughts about the performance of the AC/DC powered G2 in this review. Even though the G2 has much of the "family" sound as the NL 10.2 amplifier, its performance and ergonomics are idiosyncratic enough (largely in a good way), not to mention that it costs about one-fourth as much as the NL 10.2, that it deserves its own review.

Beast
The Edge NL 10.2 is a beast of an amplifier. Yes, it is large, but I don't think any seasoned audiophile would call it huge. Still, the handle-less amp weighs nearly 100 pounds and is therefore quite unwieldy, to say the least. It took two people to get it out of its box and upstairs to my main listening room (and back downstairs and into its box at the end of the review period). I guess most are going to place this amp on the floor, perhaps on an amp stand, but in my system it was quite at home situated on the very stable lowermost shelf of an Arcici Suspense equipment rack. If you want to classify my next statements as another spoiler alert, go right ahead:  but because of the extremely muscular yet honest sound of the Edge NL 10.2 power amplifier during serious listening sessions I was pretty much limited to listening to the analog source in my system. No, I have nothing against digital. But owing largely to the rapid pace of advances in digital playback I haven't yet convinced myself to take the plunge and invest a huge amount of money into my digital front end. I am currently using a Benchmark digital-to-analog converter connected to a PC music server to play music ripped from my CD collection and a handful of higher resolution FLAC files. I also have a nice collection of SACDs which I play on an Oppo BDP-83 Special Edition universal player. Although both the Benchmark and Oppo make beautiful music, neither can compete with the system's Basis Debut V turntable, Tri-Planar VII U tonearm, and Lyra Kleos phono cartridge fed through a Pass Laboratories XP-15 phono preamplifier. Don't assume that listening to digital through the Edge amp was a horrible experience. It wasn't. Not by a long shot. It was just when listening to a digital file or even an SACD after playing an LP through the Sound Lab DynaStat electrostatic/hybrid speakers it was fairly obvious that the full potential of the Edge NL 10.2 was only realized when playing LPs.

Tracks
Jimi Hendrix's First Rays Of The New Rising Sun is a two-LP studio album released posthumously, made from finished and partially finished tracks recorded before Jimi's death in September of 1970 that he would have presumably be on his next studio album, a follow-up to 1968's Electric Ladyland. Most Hendrix fans would have no problem with me filling up the rest of this review explaining the chronology and genesis of the assembled songs on this album, but briefly, these cuts were already released on a few posthumous albums, most notably The Cry Of Love and Rainbow Bridge, the bulk of them recorded in New York studios in 1970. I became a Hendrix fan around the age of 12, and despite the fact that this stuff is great these albums and the songs on them were never what I, or most likely anyone else I know, would call his best work. But being that he recorded only three studio albums before his death we have to take what we can get. The first appearance of the songs compiled as First Rays... on LP was in 1997, which was mastered from the 24bit/96k transfers made by the famed engineer Eddie Kramer, who worked at the original sessions. But this new LP re-issue was made from the analog masters, as part of Sony Legacy's ongoing project. What a huge difference! Yes, I know this sounds cliché, but even though I've been listening to these songs all my adult life it was like hearing these songs for the very time. And not only was it like hearing them for the first time, I feel as if in the past playing the previous issues, both the original albums from the early 1970s and since then, this material has been poorly represented. I heard this new pressing of this album a couple of times before the Edge arrived in the system. I was very, very impressed. Through the NL 10.2 it was a revelation.

There were so many sonic traits of the 10.2 that made the album come alive as never before, it was almost a mind-bending experience listening to the four sides of this album. Instrument separation is one thing, but the 10.2 was able to place each instrument and voice of the multi-track recording in a separate space of the soundstage, yet at the same time integrate the music into a complete whole. I know this sounds a bit abstract, and I'm well aware this must seem paradoxical – separate but whole, but the 10.2, despite its ability to make each instrument recorded on the album stand out from the others, was simultaneously adept at enabling all of these sounds to contribute to the organic wholeness of the music. I've never heard an amplifier perform this feat so marvelously. This is because I've never heard a solid-state component competent enough to take advantage of its ability to dissect a recording, and at the same time convey its meaning in such a way. It was as if I could hear behind the sound being recorded, with not only the details within the sound of the instrument or voice, but the sonic illusion that there was a human being responsible for its sound.

But to be honest (and at the same time less abstract), the first thing I noticed when playing this album through the NL 10.2 was its slamming bass and its macro-dynamic heft. The album opens with "Freedom", beginning with Jimi playing the chordal riff a few times after the stylus enters after the silence of the lead-in groove, and then...BLAM!, the band enters directly into my brain and body. The way the Edge was able to sort out all the sounds on this crowded recording (Jimi wasn't afraid to fill up all 16 tracks and more) and yet it sounded as if the amp still transferred every iota of transient information that was on the recording to the speakers. The tune "Room Full Of Mirrors" always seemed like an odd song to me. The high-pitched slightly out-of-tune slide guitar over the twisted electric blues was always a Jimi-type thing that I couldn't fully understand. But this pressing of the album finally pulls it together for me, and now it finally makes sense. I know the bass is credited to Billy Cox, and apologies go out to him if it is indeed him playing the instrument on this track, but I have my doubts. It sounds as if the bass is played by Hendrix through a Marshall stack with the volume turned up to 11, the playing too virtuosic to be Mr. Cox. The combination of the new pressing and the Edge NL 10.2 making the bass line now sounds as if it is driving the song. Very cool. Every other instrument recorded over and under the bass, other than the lead vocal of course, seems practically superfluous but at the same time necessary to Hendrix's vision (there is that paradox thing again). What I previously thought of as a throwaway tune on the album is now one of my favorites.

As much as I love my pair of Sound Labs speakers (and I do), I always thought that they sound somewhat forward on some material, though this is something that I am just going to have to live with. Perhaps it is due to my listening room not being as large as the speakers deserve. Along with this slight forwardness there is also a slight harshness, especially in the upper mids when the volume is pushed very high, and I suspected that this was because I often enjoy listening to the music louder than most folks do, and electrostatic speakers, as a rule, were never famous for their high-dB abilities. With the NL 10.2 in the system these negative traits in the midrange frequencies simply did not exist. At all. The midrange response of the the Edge NL 10.2 is amazing. I have no other recourse than to declare the quality of the midrange of this Edge amplifier as silky smooth, well aware that this expression is usually associated with the treble. Combined with the NL 10.2's deep, wide, tall, and immeasurably layered soundstage, the midrange enabled instruments and voices to sound spooky real, and this includes sounds on the Hendrix album that were created both acoustically and electrically. As Jimi was wont to do, he often recorded his lead vocals while he was laying down either a rhythm or lead guitar track. Often this vocal take was eventually replaced, but more often than not it was left as is. This is especially so on this album since many of the tunes on this LP set are not "finished". Somehow engineer Eddie Kramer was able to minimize bleeding of the guitar track onto the vocal track, but still, the ambiance of the studio often remains and there are many times during these songs that the midrange purity of the Edge enables my mind's ear to picture Jimi standing there in front of the mic and delivering his often strained vocals. Not only that, even though there are often multiple tracks of guitar laid down, each one can be clearly heard. During the ripping guitar solo on "Izabella", the guitar can be heard pressurizing the air in the room in which the guitar was recorded. No amplifier during the short time before the Edge arrived was able to separate the lead from the rest of the tracks with such precision and searing emotion, and no amp since the Edge amp has been returned to the manufacture has done so since.

To demonstrate the NL 10.2's prowess with real instruments recorded in a real space I chose Manuel de Falla's ballet score for The Three-Cornered Hat featuring Rafael Frubeck de Burgos conducting the Philharmonia, which was as good as any, and better than most. This record was originally issued in 1964 as EMI [ASD 608], the Alto 180g re-issue I played for this evaluation boasts quieter surfaces than the original (although I'm sure there is a collector out there that would disagree with me). This album was able to establish that the 10.2 was not only a champ at macro-dynamics, but also micro-dynamic detail as well. And the life-like reproduction of every instrument and group of instruments did not only occupy a distinct space in the soundstage, but was patently real sounding as well. When it comes down to it, that's what it's all about, isn't it (real instruments in a real space? Remember?). That also goes for soprano Victoria De Los Angeles voice which was placed between the speakers front and center, but a bit forward of the orchestra most likely because of a spot microphone, both faithful to the original recording and so true to life, listening to it was as if viewing her with some sort of auricular time machine.

Kudos must go out to the 10.2's reproduction of the treble, and this piece was a perfect excuse to revel in the way the 10.2 was able to naturally replicate these frequencies. The score of The Three-Cornered Hat borrows liberally from Andalusian folk music, and requires castanets, cymbals, triangle, tam-tam, and xylophone – with every percussive instrument involved in this score reproduced so magnificently I can only think of using the oft misused term "high-fidelity", yet in this case the definition in regards to the reproduction of sound through the NL 10.2, "fidelity" is according to the strictest sense of the term.  The cymbals, in particular, were extraordinary, as if one could hear the sound of the cymbal in slow motion – first the sound of the air compressing between the two alloyed objects, the initial strike of the instrument, the metallic rise, peak, and decay of the sizzling chime of the percussive instrument's sound, combined with the air molecules around the cymbals reacting to ultra-quick vibrations of the bronze alloy. And this added to the humanness of all the sounds on this album, it was as if I could picture in my mind a wind player's breath rising in strength to produce an audible tone, the tone of the instrument, and the air around each instrument reacting to the instrument. Wow.

The Best
It didn't take long to convince me that the Edge NL 10.2 is the best sounding solid-state amp that has ever been in my system. Does it have any faults? Only that the price of admission is so high. And that I cannot afford one. I often hear or read the term "over-built" in regards to stereo component design, as if doing so was not a imperative to acquiring excellent sound, but rather done because people who spend this kind of money on their systems require a certain level of extravagance, whether it contributes to its sound quality or not.  Does a 225 Watts per channel amp, the rated power of the Edge NL 10.2, really have to weigh 100 pounds? I mentioned to the (now former) director of marking at Edge, Steve Norber, that perhaps the NL 10.2 seemed over-built. He scoffed at the notion. He said that the NL 10.2 was built with its constituent parts and quality because that is the way it needed to be designed and built to achieve its level of performance. I believe him.

Performance
Time does not stand still. I'm sure, or at least I hope, that one day the performance of the Edge NL 10.2 amplifier will be surpassed in my system, and I'm sure I'm not alone in hoping that the amp that does this will do so for less money. For now though, the NL 10.2 has set a new level of performance that I can only hope one day will be replicated in my system. Unfortunately for me, I had to return this amp to the manufacturer. No, the lack of the presence of this amplifier has not prevented me from enjoying music in my listening room with my current set-up. But I feel very privileged to have had the chance to hear for myself what can be done in amplifier design, and delighted to have had the chance to hear it in my own home. I'm sure Edge is hard at work attempting to surpass the engineering achievements that are contained within the NL 10.2, but as far as I'm concerned they could market this amp for the rest of eternity and I would endorse it.  I'll say it again – wow.

Specifications
Type: Solid-state stereo amplifier
Power Rating: 225 watts per channel @ 8 Ohm
Transformer Rating: 2 x 1000 VA Total Capacitance: 160,000 uF 
Output Impedance: 0.03 ohm 
Constant Current Capacity: 27.73 Amperes 
Input Type: Balanced via XLR and unbalanced via RCA 
Approximate Weight: 98 pounds 
Dimensions: 19 x 15 x 9 (DxWxH in inches) 
Price: $17,300

Company Information
Edge Electronics
140 W. North Street
Kirkland, IL 60146

Voice: (815) 522-6200
Fax: (815) 522-3100
E-mail: support@edgeamps.com
Website: www.edgeamps.com