TBi Majestic Diamond 1R loudspeaker review


You’ve probably heard of Thorough Bass Inc. (TBi).  They’re the American guys that make the widely revered Magellan subwoofers.  Did you know that they also make standmount loudspeakers?  Until recently, I didn’t.  Their Majestic Diamond 1 and 1R are both portable micro-monitors.  The base model MD-1 sells for US450/AU$520 per pair whilst the higher-carat MD-1R go for US$600/AU$TBA per pair.  I opted for the latter, bundled with TBi’s Class-D Millennia MD3 integrated amplifier (which can run on 8 x AA batteries), for US$995/AU$1130.

Given the MD-1R retails for a hundred bucks or so more than the standard MD-1, I fired off an email to Jan Plummer of TBi asking about the basic differences between the two variants.  “The 1R is a little more musical. The MD-1R is equipped with a better driver and a special internal spiral port; the size is slightly larger” came the reply.  The spiral point is intended to improve bass performance.  Read all about it on the TBi website.

TBi’s MD-1R are the smallest loudspeakers to date to land at DAR for review coverage.  Their enclosure measures 15cm x 12cm x 12cm which renders them (aesthetically at least) too small for the top plate of my Atacama Aurora stands.  Each (beautifully) piano gloss-ed box houses a three inch paper single-driver and sport a small front-facing port (which spirals away internally all intestine-like).  I’m informed by the Australian distributor that they’re designed to be listened to with grilles on.  Fair enough.

The rubber feet are a dead give away: these are most likely desktop dwellers.  It’s both immediate and obvious that if you have a large space to fill you will almost certainly find greater satisfaction elsewhere for fewer dollars down.  Some folk simply cannot live without bass.  They feel that it’s omission robs music of its enjoyment.  I’m not one such chap.  Modern living spaces aren’t always convivial to such low frequency mongering and I’ve always found the imaging and speed to be of keener priority.  Being an ardent standmount fan, I am extremely forgiving of transducers that roll-off early.  TBi MD-1Rs test this resilience to breaking point.  The first few listens have me conclude that TBi haven’t even tried to do bass with these Diamonds.  They don’t resolve the bass notes of The Orb’s “Towers Of Dub” (as most standmounts can) and the tune passes me by.  Is this a good thing?  On the desktop and TV bench, yes.  Anywhere else, not really.  Read on (keeping in mind that this is one guy’s opinion in a field of thousands).

In the lounge room with Rega Brio-R [reviewed here].  Even with this most spunky of integrateds, there’s insufficient bodily mass to ride alongside more-than-satisfactory vocal handling.  Dynamics go weak at the knees in the contrasting presence of Epos ELS-8 (themselves not the most commanding personalities in the room – reviewed here).  The TBi micro monitors played nicely without distorting at lower volumes.  Tone and timbre are as they should be and nothing – bass aside – in the frequency rage is glaringly over- or under-emphasised.  Things became congested when they’re pushed too hard and that’s easily done in all but the smallest of rooms.  Running through The Style Council’s “The Boy Who Cried Wolf”, playing the game at higher SPLs things quickly stiffen, wooden…shorter of breath.  The MD-1Rs sounded increasingly restricted and constrained during the final vamp – the sound of a thousand bees trying to buzz-burst from a box.  Weller’s vocal didn’t have sufficient room to breathe and string timbres began to lose the pleasing organics of lower-level listening.  These puppies won’t “fill a lounge room” with “stunning clarity”.  Sorry.  The (always overplayed) cliche to trot out at this juncture would be that you cannae bend the laws of physics, Jim.

Switching back to the Epos after an hour or so with the TBi was akin to someone opening a window and/or switching on a light.  The lower frequencies returned flesh to the skeleton, dynamics were restored; vocals at higher volume turns could still breathe with ease.  Crossing the river from similarly-priced Epos or Usher back into Majestic Diamond country makes it tough to recommend the TBi micro-monitors for main rigs.

vs. JohnBlue Audio Art JB3 [reviewed here].   In my secondary, smaller space I wired in an Audion Sterling EL34 amplifier fed by a Schiit Bifrost DAC.  From the waist up at least, imaging, speed and vertical layering of The Orb’s “Little Fluffy Clouds” sees the two run on roughly on par.  However, the JB3 extend higher for more keenly resolved spatial cues.  Removing the grilles from the TBis went some way to redressing this imbalance.  The JB3 also manage to communicate the head-nod kick-drum and bass heft that drives this ambient-techno through the night.  Even in with diminished room dimensions, the Diamonds still sounded less than majestic.  JohnBlue has this head-to-head sewn up.  The JB3 are the missing link between desktop and small-medium room listening.  They straddle both worlds more convincingly than this smaller rival.  They’re fine on the freeway and around town.  They’re a Hyundai Accent or Toyota Corolla.

Given their shortcomings in the more traditional hifi listening spaces – lounge room and bedroom – The TBis are driven further into the margins where common-or-garden standmounts cannot go: where propulsion and drive turn tail and become problematic.  Listeners with (bass) vibration-sensitive desks who demand zippy clarity from near-field listening will likely already be one step ahead of me.  Planted direct on my head-fi centric desktop and partnered with the accompanying TBi Millennia MG3 Class D integrated amplifier, the TBis reveal themselves as Hyundai Getz – a fun ’round-town runabout whose size becomes advantageous.  Actually, no – they take the car analogy it further.  The MD 1Rs are the SmartCar of the loudspeaker world.  Not designed for being let rip on the open road, they’re on hand for those awkwardly tight spaces into which no other box dare (can!) fit.

Tighter desktop spaces. Here the MD-1R work their own furrow and they work it best with simple tunes.  Craig Finn’s stripped-back solo outing is pedestrian-paced vocal, rhythm section and acoustic strum (with occasional electric flourishes).  It’s far from the fist-pump. bar-room raucousness and joy of The Hold Steady.  The TBis lend Clear Heart Full Eyes a sticker-price-commensurate level of clarity and separation but bass line communication remains just out of reach.  Finn’s cat-growl is sometimes chesty, sometimes congested, sometimes open and clear.  Go figure.

It’s not that these TBi miniatures are egregiously weak performers nor am I dissuading you from investigating further, it’s that cheaper, more talented rivals severely blunt their edge.  In a forest of keener speaker beans, TBi’s micro-monitors are easily lost.  At six hundred clams, one is spoilt for [good quality] choice. The Diamond 1R exist in a niche (micro) within a niche (desktop) within a niche (single driver loudspeakers).  The competition’s eager bite slices deep.  One can snaffle a LOT of loudspeaker for AU$500 in today’s budget market:  Wharfedale Diamond 10.1/9.1, Usher S-520, Monitor Audio RX2 (if you’re after a half-decent standmount) or JohnBlue JB3, Qinpu V1.8, Joey Roth Ceramics, Glow Audio Voice One (if desktop audio is your focus).

Who are the TBi Majestic Diamond 1Rs for? They’re for someone seeking a teeny-tiny desktop solution – where lack of bass is not an issue but an asset (or handled by an outboard sub).  They’re for desktops where limitations reach their most extreme or where portability is essential: student dorm, office cubby, motorhome.  That the accompanying TBi amplifier can be powered with batteries hammers the portability point home. Extending this lateral thinking, the MD 1Rs could also be used to supplant (the weakness of) the drivers built into consumer televisions or one-box home theatre packages.  In this application is where I found most satisfaction.  The wick doesn’t need to be wound so high and the MD-1Rs vocal separation skills lend extra insight into the wordier world of talking heads.

In the broadest terms, TBi Majestic Diamond 1Rs prove that small doesn’t have to equate to a HUGE list of sonic compromises but that such Tardis trickery comes at a price. However, if an ultra portable, hyper compact, single driver desktop loudspeaker is exactly what you’re looking for then TBi might have that narrow niche cornered.

Associated Equipment

  • MacMini/MacBook Air + Audiophilleo2
  • Schiit Bifrost
  • Audio-gd NFB2.1
  • Rega Brio-R
  • Audion Sterling EL34
  • Epos ELS-8
  • JohnBlue JB3

Audition Music

  • Craig Finn – Clear Eyes Full Heart (2012)
  • The Style Council – Our Favourite Shop (1985)
  • The Orb – The BBC Sessions 1989-2001 (2008)

Further Information

Written by John H. Darko

John lives in the NOW + HERE = NOWHERE. He derives an income from the ad revenues of DAR. John is also an occasional staff writer for Stereophile, 6moons and TONEAudio.

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