September 2003 Reviewed by Anthony Di Marco	Coda Technologies v10 and 10.5r Amplifiers

Description Model: 10.5r Price: $3250 USD Dimensions: 19"W x 5.75"H x 12.5"D Weight: 50 pounds Model: v10 Price: $3450 USD Dimensions: 19"W x 5.75"H x 12.5"D Weight: 50 pounds Warranty: Ten years parts and labor; five years transferable

Features Precision Bias class-A/AB operation FET input with bipolar current gain Remote-controlled balanced and unbalanced input selection True DC-coupled design with no overall feedback Proprietary protection circuit guards against incoming DC offset and oscillation Remote-controlled standby circuit Double-sided gold-plated circuit boards Thirty-two 30MHz output transistors, each rated at 15A and 200V Anodized aluminum chassis

My cousin likes buying expensive watches -- for as long as I can remember, he’s bought a new timepiece every few months. As time has gone on, however, his watches have become more expensive, their names more obscure. I trust most people know Rolex, and maybe even Breitling or Omega. But I doubt many know Vacheron Constantin, Patek Philippe, or A. Lange & Söhne.

My watch is a Citizen Promaster. It’s silver, attractive, and has a reliable quartz movement that deviates only 20 seconds per month. But for the true watch aficionado, a "quartz movement" is the equivalent of a burger and fries. My cousin respects and enjoys his watches for the beautiful engineering that goes into their movements. These mechanisms are not only lovingly assembled by hand, but are accurate to within a second or two per month.

Appreciating a beautifully engineered device is something I can identify with. Each time I break open the carton of a new audio product, I take the time to look at the work that went into designing and building it. Although many mass-manufactured products are, like my Promaster, well made, they don’t have the accuracy or attention to detail, or inspire the pride of ownership, of a low-volume specialty product, in which a polished faceplate, precisely machined enclosure, and well-laid-out circuits combine to create an object that is gorgeous in its own right. The 10.5r ($3250) and v10 ($3450) amplifiers from Coda Technologies of Sacramento, California are such components.

The test of time

Coda’s two-channel 10.5r is small compared to most amplifiers, but the four-channel v10 is the most petite multichannel amplifier I have auditioned. To drive a full 5.1- or 6.1-channel system you need both units in order to get the requisite number of channels. Combined, the pair costs $6700, which buys you six 100W channels.

Both amplifiers are built on the same rugged chassis: the thick aluminum, the large, beefy heatsinks, and the 1"-thick anodized faceplates give the diminutive enclosures a rugged yet elegantly industrial appearance. Each amplifier’s weight belies its relatively small size -- these very solid boxes have the density of blocks of granite. Their construction suggests that noise induced by mechanical vibrations would be highly unlikely.

The rear of each amplifier has a heavy-duty rocker switch for power on/off, and a small toggle switch for bridging adjacent channels. Inset into the front faceplate are two buttons: Input Selector switches between balanced and unbalanced operation, while Bias enables current flow to the final output stage of the amplifier. The Bias button allows the amplifier to be powered up while keeping the speakers safe, and maintains the temperature and stability of the circuit so that no warmup period is required. Under a thin plastic window, three LEDs indicate whether the amplifier is powered on and whether balanced or RCA inputs are being used.

High-quality Neutrik balanced and gold-plated unbalanced connections stand out against poorly spaced plastic binding posts that were an absolute pain to torque down. Still, the binding posts and the plastic covering the LEDs were the only disappointing aspects of the Coda’s otherwise handsome, well-made chassis. The company’s director of marketing, Mark Ward, assures me that the binding-post issue has been resolved with heavy-duty Cardas posts. Anyone who currently owns a 10.5r or v10 with the cheaper posts can send their unit back to Coda to be retrofitted at no charge.

A look inside the 10.5r and v10 reveals how serious Coda’s engineers are about circuit design. Only a few inches of wire connect the amplifier’s main board to each single-ended input and speaker binding post. In addition, a single ribbon connector handles the front-panel controls. All other signal paths follow embedded traces in glass-epoxy boards. But Coda doesn’t stop there. To ensure long-term durability, resistance to corrosion, and the elimination of noise, each circuit board is coated with a barrier made of an alloy of tin and nickel and plated with corrosion-resistant gold. A shielded toroidal transformer helps keep internal electromagnetic noise to a minimum.

The 10.5r and v10 share the same DC-coupled design: no capacitors are used in the signal path. Coupling capacitors are known to induce phase shifts and cause high frequencies to sound brittle and grainy, according to Coda. This distortion can also manifest itself as instability in the stereo image, and induce listening fatigue. Both amplifiers run in class-A up to 25Wpc. If a quartz movement is considered fast food to a connoisseur of timepieces, then class-A/B can be the soft drink that washes it all down. Coda alleges that running output transistors in class-A generates the same even-order distortion of tube amplifiers. According to them, odd-order harmonics cause listening fatigue, while even-order distortion exists in the resonant properties of musical instruments.

Gold-plated circuit boards, DC-coupled design, shielded power transformers, and limited use of wire not only give the interiors of the 10.5r and v10 a jewel-like appearance, but also furnish them with very wide bandwidth. Each amplifier has a specified frequency response of 0Hz to 100kHz. This reportedly removes noise from the audible spectrum, as well as from any frequencies beyond human hearing that can affect the sound. For instance, the frequencies of 40Hz and10kHz have harmonics from 20Hz on up to 100kHz. Although human hearing doesn’t extend much below 40Hz or much above 15kHz, the purity of these sub- and supersonic frequencies is critical to such audible phenomena as the decay of cymbals, the overtones of a musical note, and the ambience of a recording venue.

Winding ’em up

I found that bridging the v10 or 10.5r required using the amps’ balanced connections. Because I didn’t have a balanced system I simply used three of the v10’s four channels. The v10 powered my center and surround speakers, while the 10.5r handled the front left and right. Those who have processors with balanced outputs would be able to bridge two of the v10’s channels to form one 400W channel with two 100W channels -- or, if the need arose, bridge all four to create a very powerful 400W two-channel amplifier. In my configuration, the fourth channel could also drive a passive subwoofer.

Other than running wires and selecting the appropriate input, I found setup to be simple. And although the Codas lack a 12V remote turn-on, Coda does supply universal remote controls that will operate the input and bias switching as well as manage other components.

Like the gentle tick-tock of a clock

I love these amplifiers. At no point during my evaluations did the Coda 10.5r or v10 not deliver superb sound quality. Their sonic signatures were ones of speed, harmonic richness, and impressive detail, nor did they roll off high frequencies or compress dynamics in an attempt to add warmth to the sound. These were very dynamic, very high-resolution components that revealed texture in recordings and infused images with weight, presence, and an uncanny realism.

All the high-frequency information in the "Bee Dome" sequence (chapter 11) of X-Files: Fight the Future was reproduced clearly, but, unlike other amplifiers, the Codas gave each bee its own sonic profile. The bees no longer sounded like sound effects hovering in midair, but like actual insects with individual sonic details and pitches. Sculley and Mulder’s voices displayed a fullness that gave distinct outlines to their faces and physical forms. Clothing, footsteps, and human breath all had mass, which made them appear and feel more tangible. The agents’ voices sounded so real that I lost count of the chills that ran down my back.

Not only people but places, too, emerged from the surround image with more concrete presence. The Coda’s fullness and high-frequency purity allowed visuals to appear within my room with three-dimensional scale and depth. The gigantic industrial fan that greets Will Smith in chapter 6 of Men In Black looked even more imposing. As they pushed air through the MIB agency’s front foyer, the blades of the fan seemed even heavier, the air more dense.

With every film I sampled, it was if the Coda was replicating the sense of gravity possessed by real objects and living beings. Everything felt more real, more accessible, more there. The rich, colorful images in Amélie were perfectly complemented by the rich ambience of the film’s soundtrack. The sounds of Paris’s Montmartre district heard throughout this wonderful film were beautifully layered and separated within the images.

Many amplifiers favor certain frequency ranges. The midrange may seem a bit too forward, or the bass too full. Or high frequencies may sound exaggerated to make up for a lack of extension. The 10.5r and v10 didn’t seem to play any favorites. The guitar in Jesse Cook’s Gravity [Narada ND-63037] sounded full, but quick and sweet at the same time. I don’t know how many times I listened to "Luna Llena," but each twang of Cook’s guitar string launched overtones into the room without losing the detail of the initial pluck. An overly warm presentation would have made the twang sound slow and too thick -- the result of harmonic structure collapsing into one indefinable heap. But even with less-than-stellar recordings, the Codas never ignored the harmonic structure or sapped the music’s soul.

The strings on track 3 of Music for a Glass Bead Game [John Marks JMR 15] can sound slightly strident and unexciting if an amp is on the lean side of neutral. The Codas injected sweetness into the strings without killing the detail, which drew me in and allowed me to forget I was listening to an electronic reproduction.

The bass of my Canton Ergo speakers has a tendency to sound a bit lean and dry when I use the wrong amplifier. Driven by the Codas, the Ergos’ bass possessed weight, but didn’t lumber along or get too punchy. The sexually charged bass line in "Butterfly’s Dream," from Tim Booth and Angelo Badalamenti’s Booth and the Bad Angel [PolyGram 526 852], can sound too forward and fat, but here it exhibited the appropriate amount of ripeness while keeping the bass tight and detailed.

Mary Black’s No Frontiers [Gifthorse D2-77308] proved once again how engaging music can be when notes have a chance to build and decay without being cut off or artificially enhanced. The guitar and cymbals on "Vanities" and "Fat Valley of Pain" were reproduced with all the sparkle and shimmer that make these songs two of my all-time favorites.

Multichannel music did not reveal any surprises. The dense nightclub atmosphere on John Pizzarelli’s Live at Birdland SACD [Telarc SACD-63577] was retained, while the raspy, soulful quality of Sting’s voice on Brand New Day [DTS 91061] exhibited an authority and weight that eclipsed those from other amplifiers. The 5.1-channel soundstage demonstrated the same weight and presence I’d heard while watching films. But listening to music only, everything sounded more natural and realistic.

High noon

Does having two completely separate chassis offer any benefit to music reproduction when compared to a single-chassis solution? Answering this question turned out to be tougher than I’d thought it would be.

The Pass Labs X5 ($4500) is a well-made multichannel amplifier that houses all of its five channels under one roof; together, the Coda v10 and 10.5r offer six channels of amplification in two chassis. The Codas cost about $1117 per channel, the Pass $900. I can’t tell you that the Codas are built that much better than the Pass Labs, but the 10.5r and v10 do have a slight edge in terms of fit and finish, especially when you factor in the new Cardas posts. My wife preferred the Codas for their smaller size and "cuteness." The X5 has a face only a man can love. Both are, however, made with the attention befitting a Swiss watch

In terms of sound quality, the Pass Labs X5 perfectly fits the audiophile concept of "transparency." Compared side by side, however, the Coda beat the Pass in terms of musicality and texture. I can say nothing negative about how either design handles high frequencies. Both have shimmer and refinement to spare, with no glare or harshness -- though the Coda is sweeter. In the mid-frequencies the Coda was flat-out more seductive, but was not mushy, or what some audiophiles call "syrupy." The 10.5r and v10 revealed more harmonic texture, while the Pass left any "magic" to upstream components. Overall, the Codas injected a bit of their own sonic signature, while the Pass stayed true to the formal definition of an amplifier: to add gain to a signal without injecting any personality of its own.

When I compared the multichannel v10 to the X5, the Pass Labs sounded more dynamic overall, but the v10 managed to pull me more into the music. When I added a source with more warmth, such as Audio Analogue’s Paganini CD player, the differences were less apparent. Still, my upstream components didn’t offer enough of the Coda’s magic to compensate for the Pass Labs’ cool neutrality.

The Coda v10 and Pass Labs X5 are both excellent examples of first-class engineering and design. The degree of the differences between them will depend on what upstream components and speakers you have, as well as your space restrictions and decorating taste. In my room with my system, I preferred the sound of the Coda.

Time’s up

I had not heard of watchmaker Patek Philippe before my cousin mentioned him. I doubt my cousin has ever heard of Coda Technologies. But I’m sure that if he took a look at the Coda 10.5r and v10, he would realize that we are not that different in our obsessions.

Like a watch precisely designed and built, the Codas go about their business accurately and reliably, with a minimum amount of deviation from neutral. Both amplifiers not only succeed in delivering beautiful sound, but also are fine-looking, with construction that should stand the tests of time.

Manufacturer contact information:

The Continuum Group
8274 Mediterranean Avenue
Sacramento, CA 95826, USA
Phone: (916) 383-3653
Fax: (916) 386-8296

E-mail: info@coda-continuum.com
Website: www.coda-continuum.com

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