I've always had the passion for subwoofers: I've always inserted them into my hifi installations, and my last one, for many years has been the Gravis from Sonus Faber, a great-looking passive mono, it looked like an artisan-made table, with undoubtable sound quality, and an equally good "WAF" effect, an element that doesn't lack its relevance....notoriously.

Having found an Italo-Romanian vintage enthusiast that bought it from me, I decided to invest the income in technologically up-to-date renovation of my main installation's Sub section, and wandering on the web to find the best solution, I found TBI, of which I read many great reviews and decided to make the purchase, hoping to "blindly" make the right choice, as I did for the passive pre, Sonic Euphoria.

Apart from that, "on the paper" TBI's subs got to the point of my basic requirements: they're passive (personally I am convinced that of the superiority of this type of solution, because it gives many more architectural possibilities, compared to amplified subs which today actually are more widespread), and less occupying in terms of space, remembering some previous experiences, so I decided to purchase a pair of the more performing model, the MAGELLAN VIII, together with a pair of small 150 Watt speakers, the TBI 200, which have an adjustable 50-150 Hz internal crossover, apart from the volume and phase control, used as mono for both Magellans in this configuration.

Jan Plummer patented a technology named ETL^TM, which I'll now try to explain using the information that Jan supplied to me in addition to what is published on his website: the solution of the many problems connected to the making of a diffuser is to divert from the Thiele/Small construction method. Primarily the T/S parameters govern the playing of the low frequencies, but nobody paid attention to the structure of the speaker and how that is related to the other frequencies. Some say that apart from the bass drivers, the other speakers would work better in the open air. Plummer's studies demonstrate that the back wave can be manipulated better than the free air, or the total frequency absorption, as it happens in traditional speakers.

TBI makes speakers which are smaller than the ones the concurrency makes, but which are extremely "fast", be it full-ranges or subwoofers. The base principle of their property technology is to apply constant pressure to a single full-range inside a speaker, without a definite dynamic volume and a system that nears a transmission line, but without becoming one. It is tightly connected to the electric signal that gets to the cone and instantly determines its position: this type of system reduces the influence of internal and environmental resonance.

The result of such technology is what got to my doorstep: two black completely sealed "boxes", the drivers (one for each speaker, 90 db and –3 db response between 15 and 100 Hz, all in just 8 inches), which aren't visible, the only opening towards the outside is the reflex system connection tube, roughly big as a tower PC, perched on little conic "legs".

As for the positioning, I followed the instructions. I put the subs side-by-side between my QUAD 988's, a bit set back from the electrostatics and half a meter from the wall, connected to the finals by ATLAS Hyper, remembering the great performance of John Carrick's cables in the low region of the audio spectrum. The signal got to the dedicated finals through a Y-shaped adapter that allowed full-range signal transfer to the OTL's which "feed" the QUADs without any crossover interposition.

But just how should a subwoofer sound?

In a full system it has to return the low field coherently, "descend" authoritatively and with adequate softness, if tweaked the right way its emission should "vanish", without being noticeable when not "needed"; actually in my experience an optimal insertion of a sub in an installation that really needs such an addition, improves not just the low area of the spectrum, but all of them, contributing to a better rendering of the audio image, even in sound situations in which "apparently" the sub shouldn't participate seen the frequencies. For example, I always noticed an improvement in the voice, as if (and probably this is the case) some harmonics were added, that otherwise would have been lost: it's a bit like the supertweeters that often get the same effect, though restricted to the higher frequencies.

So how do the Magellans sound?

Premising that, having verified both solutions, my impressions are referred to a stereo configuration that has the two subs acting without any signal summing, a situation much much more preferable to just one sub in two-channel audio, to demonstrate the fact that low freqs aren't directional I must say that Jan Plummer's speakers do EXACTLY what a sub should do in an absolutely great way: record upon record I appreciated their participation a lot, after finding the right crossing point with the QUADs at ca. 70Hz, and the right listening volume.
Compared to the Gravis, (ok, I'm just remembering but I perfectly have its sound in mind) the Magellans immediately appear more precise in the deep bass area, and over all much faster, confirming themselves as ideal partners for my QUAD 988's; the rendering of the organ's lower register is great, solid, without being too invading and with no mention of "boom" effects or the presence of bad-sounding unnatural elements.
These aren't spectacular, but highly musical objects, fine enough to be valid companions to the extremely fine QUADs.
Their insertion improves the sound scene in height and depth, as I said above, the voices, especially the female ones become more solid, the drums are perfect, the drum skins are there, three-dimensional and perfectly inserted into the virtual sound scene, and the cello strings are much more present, an effect that was only partial with the electrostatics alone.
The keyword of the Magellans' sound is balance: they aren't objects made to amaze the audience, in fact probably they don't get to 12 Hz, but they surely do get to 20 Hz, and their presence for example in the full orchestra moments they're perfect in sound message articulation, and an interaction with the QUADs which makes me think of just one word: natural.
I think it's safe to say that the Magellan VIIsu are the best subwoofers that I've had the occasion to listen to (and through expos, stores and friends, apart from domestic use, I've gotten quite a bit of experience "in the field"), and certainly in their price range they have no rivals.
The system I installed in my house costs altogether $3.300, to which you have to add the S&H costs, so let's say that, putting things simply, with about 3000 – 3200 € you can take home the system that comprises two subs and two dedicated crossover amps, that's not exactly a tiny amount but it's safe to say that you can't find anything better if not at a much higher price.
I have to say, apart from all, that even an only subwoofer used with its own dedicated amp, summing up both channels, performs more than adequately and the cost consequentially is divided by two so the purchase becomes absolutely competitive.
I personally prefer The stereo solution, but honestly it can be seen a san upgrade which can be made even in a later moment, as the differences (which are present) aren't enough to make the second sub "mandatory" but only "very suggested", to obtain the maximum results possible in reference systems, and a price comparison in this case should be done hypothesizing a pair of units from another maker.
For the amplified sub enthusiasts, there is an amplified version of this model and another one, always amplified, with a higher sub participation cut. I didn't have occasion to try the Magellans in a five-channel home theatre system, but I think you can safely use them that way, if their buyer isn't searching for the effect in itself, but an audio performance that is coherent with a hifi predisposition.
Perfect companions fot the QUAD 988's, with which they form an absolute reference system that will consistently improve with their insertion in all the parameters of listening, the Magellans are highly recommended, they are worth the purchase, not just the test.

******

When I let Jan Plummer know about the positive outcome of my tests on the sound of his subs, and about my intention to publish a review on the magazine, he offered me to try his new mini-speakersthe Majestic Diamonds, that "survived" a "journalistic disaster" on 6 Moons, Srajan Ebaen's on-line magazine that was later "mended" by a follow-up.

Suggesting to follow the instructions for use attentively, Jan sent me by express courier, and a few days later I got the Diamonds just in time to put them in this review dedicated to TBI products.
The Majestic Diamonds, sold at $200 the pair, are little "cubes", of really small size(11,5 cm X 11,5 cm X 14 cm), one-way and with a reflex small woofer: these are the smallest speakers I have ever listened to, except the two hemispheres included with my iMac.
They have a resistance of 8 ohms, an 87 db sensibility and a declared frequency response ranging from 80 to 18000 Hz — 6db Even if it's possible to use them on stands following the instructions I put them on the bookshelf, about 70 cm from the floor level, this being the best listening solution.
The booklet indicates as NECESSARY the presence of the front net that is an essential element of the audio performance. The speakers come with two rubber plugs that should be used to close the small frontal reflex connection tube, when the Diamonds are used without any crossover, i.e. full range speakers. I tried this solution, always using them this way, but I found that the plug downgrades the sound significantly, since it appears more closed and padded so the opinions that will follow will regard the standard setup eithout the plugs (actually in the instructions it is clearly stated that the speakers sound "better" this way), without noticing any power resistance problems, as the booklet said.
I put the Diamonds in my domestic systems in the place of the QUAD 988's and the Triangle CELIUS 202's, respectively amplified by my OTL's and by one of the two MF XA-50's normally used to passively biamplify the French, and as a source I had the LECTOR Digidrive/Digicode pair and the Rotel 971 modded by Fabio Camorani, and in both cases the Pre was the "usual" passive Sonic Euphoria, as for the signal cables, I used QUAD cables normally used for the electrostatics and two "real tow-ropes" made by the American Luminous Cable, the SYNCHESTRA SIGNATURE, and here go my impressions, used as the only speakers, and also paired with the Magellan Subs.

Already in the first notes, the characteristic that immediately is noticed, is the focus depth of the soundstage, really great and dimensionally perfectly coherent: record upon record this sensation is constantly confirmed, the sound planes are perfectly reproduced, and you can appreciate, for example in the choir piece from the soundtrack of "Brother Sun, Sister Moon" by Ritz Ortolani ("The genius of Ritz Ortolani", BMG 2004), the positioning of the two choirs around the listener, the male is a bit "set back", and the higher voices are up front. Another record which reveals a lot of the Diamonds' capacity of making a wide and deep soundscene, is the beautiful CD "Dorian Sampler Vol.II", from the late American label
The Diamonds are "kind" speakers that pair up perfectly with my valve systems, that are the type of amp that interacts better, in a very natural performance, with the TBI's, you don't notice any nuisance in the listening, no sharpness, that will only appear if needed in energetic terms by way of Musical FIdelity solid-state amplification, which is what they cannot do.
Associated to the subwoofer they compensate the obvious but not annoying limitation on the low freqs, they sound coherent and articulated, the Diamonds excel above all in the performance of chamber music: Ludwig Guttler's trumpet (CD Capriccio Digital 1985) in the Concert in D major of Greog Telemann (that is nothing more than the "Canzone dell'amore perduto" by De Andrè) is perfect, carved in the center of the scene and the strings are rendered with great fineness and nature.
Éassing to jazz, the splendid CD "The life of a trio: saturday" by Bley, Giuffre & Swallow (Universal 2001) played on the little "babies" doesn't make me regret the QUADs , ok, the TBIs di not have that great precision that the english speakers have but perform in an unexpected way if you consider the price difference: Bley's plane is extremely realisic, Swallow's cello solo (Track 9) is rendered perfectly with a notable ambience, especially (that's nothing new) if listened to combined with the Subs
Even Rock music sounds good (well, we're not talking about super-aggressive or fast speakers, but the non-"formula 1" parts are very coherent) with more "monitor"-type effect, that normally throws the voice very much forward, but here they get more focus depth, thus sounding remarkable.

As for the voices, Gino Paoli and Cecilia Chailly ( CD "Faber Amico Fragile" BMG 2003) have a material consistence and the air around, the ambience of the Carlo Felice theater, where the live performance was recorded, are reproduced in a perfect way, particularly the thin and very acute voice of Chailly nears the QUADs' performance, and I think this is not a little thing..... to confirm the "cubes"' great performance in the medium spectrum.
The slight roll-off on the high freqs doesn't influence the acutes' rendering, in fact this is a "soft" but precise speaker, that allows us to evaluate the differences between the carvings and the electronics it's associated to, a declared hifi object: an unexpected performance if we consider that everything comes out of a small one-way woofer.
Associated with the Magellans they offer a high-level performance, alone they are limited only on the low frequencies, but "where they get" they get in a very valid manner with a present and controlled bass without smudges or uncertainties, attention is to be only directed to the amplification to associate the Diamonds to: it shouldn't be too powerful, or the general performance will be a bit "hardened", the ideal I think is a valve system that would perfectly "understand" their mission of "gentle listening companions", not ear-aching, but delicious.
Comforted by this experience, I decided to make another experiment: My son Andrej already for quite a bit was asking me for a system of his own, seen my experimentations with home audio, to listen to his "horrid" favourite music and his beloved MP3s.

The system I put the Diamonds in, (put on the sides of my son's PC monitor, a bit lifted from the desk, at ear height, using two wristwatch boxes filled with sand as stands) was made of an AIWA portable CDP and the "legendary" T-amp, connected to the AIWA with a stereo cable with minijack termination.

In my test of the T-amp published in the last number of VIDEOHIFI I said that the insertion of TADDEO DIGITAL ANTIDOTE to the exit of the CDP had improved clearly the sound of the T-amp, well the same thing happened in this configuration: the Diamonds seem to be the ideal companions of "the magic box " and, they go to constitute a system of great interest from the point of view of the total sound performance. The softness of the TBIs compensates the rough aggressiveness of the sound of the amplifier in D class that had annoyed me in my previous test, their result in the reproduction of a deep sound stage concurs to let you appreciate a finally realistic acoustic scene, compared to the what often happens to our children with the loudspeakers of the monitor. Here we are truly on "another planet" and are speaking about a "budget" configuration that I believe corresponds to the use that the T-amp had been made for.

Apart from that we should recognize Sonic Impact's amplification's ability to make the not-too-efficient American speakers sound "strong" and seamless: we're not in front of a "giant-killing" system, but a very good result at a cost which altogether is low, and then if we think that the T-amp works also with batteries like the CDP and thus the system is easily portable, maybe we found the best field trip "compact pack" retrievable on the market today

Well, at this point I think that more than my opinion, it would be more interesting to know what Andrej and Dimitri (respectively 17 and 16 years old) think, recruited on the field for an impression from their point of view, and from the side of their favourite music:

"The speakers look essential, simple and compact, and easy to position practically anywhere. But let's not be deceived by the size, that could look small: in fact inside the Diamonds, piloted by the small T-amp that we actually discovered just today, lies a sound power that is a lot more than the speakers in the PC's monitor, that we used before, accompanied by a lot more precision and clarity. Another advantage on the PC's speakers is that the Diamonds are detached from the computer itself, so they cen be positioned practically anywhere. From a simple comparison between the two solutions, one can sense the TBIs' remarkable superiority: first of all the sound is more clear and squeaky-clean, in fact, turning up the bass in some songs that are particularly bass-rich, the PC's speakers slightly distort the sound, while the Diamonds hold their round even in high-bass situations without distortions and/or defects"

I think it's appropriate to define the Majestic Diamonds as the Rocky Balboa of speakers, they are brave champions that courageously confront other speakers, which are economically much more heavy, and notoriously and undoubtably well-sounding: just as Rocky they receive their blows... but they land their hits, too, in the "fight", and we're talking about speakers that cost respectively 10 and 30 times as much. This is their best trait in my opinion: a very "audiophile" disposition, and well, if you have to give something away in terms of the extreme of the low frequencies, actually declared in the specs, their mid-frequency band and their capacity of reproducing the sound stage realistically, especially with chamber music and Jazz, is extraordinary.
But the real revelation is in their use in systems of apparently low lineage: the Diamonds look "born" for small places, amplified by the "legendary" T-amp with synergy (which after all is the real key to every good-sounding hifi system) and results that bring me to recommend each possessor of the T-amp this kind of experience: they won't remain in delusion.
Easily put in any room, with a sound that is delicate and fine, the TBI Majestic Diamonds can be a winning choice, especially combined with "at least" a Magellan VIIIsu, to represent a high-level system's front-end at a cost that is acceptable, alone they are extraordinary for use in a secondary system that from them can gain that little touch of "audiophile", that never harms even in a lower-budget solution; I didn't have an occasion to try this but I think, for the above reasons, that 5 Diamonds and a Magellan could make up a great alternative to a home theatre system in which we would like to advantage quality instead of external beauty of the system.
As a solution to make our children's MP3 way of life sound better, or to listen to the many high quality radios we can find through our PC and the Internet (Yes, Broadband does miracles...) that certainly deserve more than the sound of our computer speakers, together with the T-amp this is a great discovery, that I just can't invite you to make for yourself, $200 aren't nothing, but the real great sound always has a price, and the one of the Diamonds looks very honest to me, seen the obtained results. TBI, in Marietta, Georgia, is a small reality, with big projects, as its proprietor-designer says: "Our objective is to become number one among the speaker making companies, bridging the gap between high-end products, and those oriented to the mass market".
What can I say at the end of this double review? Jan Plummer does have the bases to get what he wants... well, we'll see what he'll be up to in the future...