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Positive Feedback ISSUE 26
july/august 2006



506 loudspeakers - To the Manner Born, Tetra's Glorious 506 Hotrods

as reviewed by Jim Merod



Kicking It

A recent rumor leaked through the impregnable seal I've used for decades to free myself from rumor, innuendo, grousing, harumphing, and all related forms of representational balderdash.

I'm not happy about this breach of my hermetic self-enclosure. Perhaps it explains the bad humor of this affirmative review.

Years ago, in the mythic pre-"nine eleven era" of audio bliss, I committed my usual folly of dropping into Las Vegas for the annual year-launching jousting at the Consumer Electronics Show.

I can't help myself. I've got friends I see only once a year near the craps tables (read the irrepressible Greg Weaver and the brilliant Serguei Timachev). They wait, elbows on polished oak bars, at fancy west Nevada watering holes once haunted by Dean Martin and Frank Sinatra. Where is the Rat Pack when you need a good laugh?

I'm nostalgic. Or loyal. And sentimental. I believe friendship counts for something. I've been known to gurgle in my beard lines such as these: only those who warm the heart's deep core are worthy of the small evaporating precious time we share on earth.

The Revolution on View

You can't launch a philosophical movement on faith in fellow-feeling, since god-inspired (text-dominated, cleric-demented) movements around the globe resemble disembowelings.

Years ago, in Las Vegas, as I averred above, meandering took me to a room with the lonely name "Tetra." Feeling sorry and curious, since on inspection the startled instruments inside looked like rocket ships, I sauntered in. The conversation went something like this:

Them: "Howdy!"

Me: "Yo."

Them: "Grab a seat."

Which I did. A quarter of an hour later, sunk into a mushy sofa in the near "sweet spot" between two rocket launchers belching awe-inspired sound, I looked over at my host and restarted our aborted conversation.

Me: "Amazing."

Him: "Glad you like 'em."

Me: "What are they called?"

Him: "Lives."

Me: "No, I meant the speakers."

Him: "Right ... Lives!"

Me: "Okay ... . "

Adrian Butts doesn't waste words. As my laconic but enthusiastic host that early January afternoon in god forsaken Vegas, he clearly wanted a visitor to hear what was going on with no interference. Across the years I've known and respected Adrian Butts, that precise character trait―letting his audio design work speak for itself has shown itself at the heart of his outlook on "things musical." Adrian Butts is one of high-end audio's inspired romantics, a man who leads with his heart. No doubt that is part of the reason he is well connected with sponsors, supporters, and hall of fame musicians who attest to his speakers, such as Keith Richards of the somewhat highly regarded Rolling Stones.

I cannot know if, as I suspect, I was the first "audio reviewer" (isolationist-inclined, hermetically protected critic) to genuinely "get" the Tetra take on sound and music. I was near the first. The line continues to grow long.

Plunging Forward 

That was then, enviable pre-nine eleven days of sonic bliss and musical engagement ... in which no red states, blue states, and foreign carnage wracked anyone's furious attempt at hermetic sealing. Music, after all has died down, is "all."

A decade later, Tetra stands tall and proud with a series of "to die for" speakers and an already (before-arrival) mythologized speaker with boatloads of pre-production hype. The almost here Tetra 606 statement speaker is a sonic instrument desired (and on order) by Herbie Hancock, Benny Golson, Ron Carter and others of such good taste and musical awareness.

My point here, as you've suspected, is that despite a lame and genuinely discreditable rumor a year ago or so―that Tetra's glorious 506 speaker did not measure up to strong reviewers' declared admiration―such derogation was once more (as Mark Twain noted about announcements signaling his death) "premature."

If you're the sort of listener who does not trust your hearing, you may be misguided in any audiophile inclinations you follow. No one can tell you, or show you, or convince you that a truly great sounding system is garbage if you, on your own evidence, hear its glory. At least, no one should convince you to disregard and disrespect your hearing. The German language has it right. "Gehoren" and "horen" are verbs that amplify one another: believing is hearing. To hear accurately and engagingly is truth.

Hearing is Knowing

I do not trust sales people. Self-interest trumps any possibility of objectivity. I do not trust reviewers. Objectivity easily succumbs to a thousand blandishments and fogs of personal enchantment. This suspicion extends no less to academic intellectual work and to legal opinions rendered on high. The sorrow of our era―before and after nine eleven, as well as its fatuous strategic reach all the way back to the post-bellum American nineteenth century―is the irremediable cultural turbulence and entrenched mood of crisis across every tier of human endeavor that defines such a long historical span.

No profession, no cadre of artistic or critical workers (the once adroit, potentially self-purified creative proletariat) stands apart beyond culpability, implication. Such a universal indictment can be read within the seams of "global warming." No one who drives a car or operates as an ordinary citizen of the so called "first world" escapes responsibility for the less that earth's future seems to promise.

Such declaration, against the grain of the convivial ethos that defines audio review work, emerges not as a flag of contrition or defeat. Challenge or accept our plight. The fact as I see it―a necessary awareness―is that, if we listen to late Beethoven quartets and contemporary jazz explorations; to classic rock fulminations and the triumphant harmonic clatter of Bach or Mozart ... we begin to take on responsibility for conditions of reception. We listen as members of a tribe. That may seem obscure, but think about the "circle" of your coming-into-audio-and-musical awareness.

I do not mean the "Club of Smug Officers" who administer Audio Truth (an oxymoron for morons without requisite musical "edu-macation"). Such flatulent conditions are all around. The "experts" who dictate what the audio proletariat believes resemble grinning abdications, Halloween figures dressed as Shakespeare's perennial Fool, a posthumous incarnation ("in life") of corrupted ease. Against our ears, against the truth of concrete hearing, imagine Tinker Bell's jovial philosophy... hilarious, jovial, trivial, contemporary.

We, who ignore the where and when and how of our predicament, as thinkers and listeners, abandon audio and cultural savvy. To wit, Glenn Gould's comment about "the hopeless confusion that arises when we attempt to contain the inscrutable pressures of self guiding artistic destiny within the neat, historical summation of collective chronology" [The Glenn Gould Reader, ed. Tim Page (New York: Knopf, 1984), p. 86.]. You recognize his target: expertise in the guise of benevolent fraud.

Therefore, anxiety notwithstanding, consider this modest but small unwavering review a statement of personal belief―flawed intelligence well-trained but humble knowing that the best it can accomplish is an oath to tell truth as it can. One takes oaths upon a favored "bible." In my case, upon Michel de Montaigne's collected essays―the closest texts I know to truth-telling, warts and all.

Bottom Line: Seeking Closure 

Tetra's 506 speakers sat in the center of my mastering rig for almost six months of constant listening. They underwent listening that had serious professional outcomes for me and, thus, carried sonic evidence with strict consequences. They endured scrutiny of the sort only the most refined single malt scotch can match. They worked with ease and comfort in every sonic circumstance I put them to: symphonies; a capella vocalists; jazz trios; salsa groups; rock (Credence and John Fogerty); as well as the gamut of recordings I made across the almost six month span of the 506s residence in my mastering set up.

Here's what I'll attest to (sworn on Montaigne's sacred texts) about their performance. Tetra 506s give enormous musical pleasure. They are a truly "musical" sonic instrument. The 506s give deep insight into recorded soundstages, important if you are an 'on location' recording engineer. Few speakers I've spent extended time with have convinced me that they are able to reproduce the size and dimensions of an actual acoustic environment. The 506 are take-no-fool-alive instruments that somehow "know" what stage you recorded a band on. That's impressive to me. That's one of the genuine measures of audio and music reproduction.

Tetra 506s are subtle and dramatic all at once. They erase the line between musical joy and sonic truth. They are truth-telling while being musically vivid at every moment, in every way. That's impressive to anyone who lives with them.

These several issues are worth dealing with honestly and bluntly. Number one. Would I like to own the Tetra 506s? Yes. Number two. Do I own any Tetra speakers? Yes. Number three. What speaker would I prefer to own more than the 506s?


One. Tetra sold the pair of 506s I was reviewing. I had to send them off in their substantial crates to their waiting purchaser. Two. I own Tetra's original small bookshelf speaker (Manhattan 105s) which I regard as an ideal enhancement for a superior computer-based sound system or any small room or apartment that needs to minimize a system's footprint. I also own the Tetra "Kids" (now the Manhattan 305s), which I reviewed and purchased: a truly great floor standing speaker, in a class with speakers far larger, more expensive. Three. I'd prefer someday to own the already near-mythic (soon to be shown) 606 speakers. Why? If Ron Carter and Herbie Hancock are inclined to put their money toward them, who am I to disavow earnest curiosity?

Consider my personal statement of admiration here (i) a review; (ii) a confession; and (iii) a promise of a listening happiness. However you receive it, consider this. Tetra's history of commitment to honest sound, musically and emotionally engaging, sets one of several ineradicable industry benchmarks for speaker craftsmanship.

The 506 speakers continue that tradition. Jim Merod


  • Freq. Response: 2920,000Hz

  • Sensitivity: 91dB (2.83Vrms @ 1 meter)

  • Impedance: 8 ohms (nominal), 7 ohms (minimal)

  • Crossover Frequency: 3k Hz

  • Woofer: 8" Morel NeoLin, Neodymium Damped Polymer Composite

  • Tweeter: 1" Scan Speak, Treated Fabric

  • Power handling: 500 watts per channel

  • Weight: 95 lbs (43.2kg)

  • Dimensions: 43" H x 19" W x 19.5" D, (109 x 48 x 49 cm)

  • Recommended Room Size: medium to large

Tetra went all out in designing the 506 tetrahedron-shape. It's an equilateral pyramid, one of the strongest structures known to man. The 506 also features an elegantly art-deco styled cherry baffle.

The 8" Morel NeoLin woofer features Neodymium Damped Polymer Composite for excellent power handling. Its tremendous dynamics allows for clean and crisp sound at high volumes. The 1" Scan Speak treated fabric tweeter is characterized by a very smooth and slightly rising frequency response with unparalleled accuracy and detail.

In the pursuit of Tetra's signature Being There sound, we design with simple, elegant crossovers and low parts count. Using 12dB per octave roll-offs, the drivers run conservatively within their operating range. Crossover points are cherry-picked by the design team.

We designed our own Clarity cap and utilize the finest Hepta-Litz Air-Cored inductors. The crossover is hard-wired point-to-point, there's Cardas internal wiring and gold-plated rhodium binding posts. The best part is the 506's easy to drive 8 ohm impedance load at a full 91dB sensitivity (2.83Vrms @ 1 meter).

Of course, while we do make our exceptional NRC measured performance data available (see table below), they don't quite tell the entire tale of the Tetra Being There Music Experience. The rest of the story is how wonderful your music will sound, a quality not easily measured, even by the NRC.

Tetra has always benefited from the balance between enclosure design and Adrian's orchestration of drivers and crossovers. It's the delicate balance of these three key elements that confer our speakers with clarity, detail, harmonic fullness, plus expansive, room-filling ambience. The sweet spot is wide, come on in!

The 506 is available in a durable satin black or a deep high gloss finish. The front cherry baffles are available in red, black or natural color. Custom colors are available upon request.

The 506 is supplied with light weight custom dust covers that secure magnetically to the baffle. We also provide solid brass cone footers, and adjustable bi-wire jumper plates. The 506 sports two sets of Cardas Gold/Rhodium binding posts to allow for bi-wiring or bi-amping.

Retail: $9750 pr.

Tetra Loudspeakers
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