KEF Blade Two Meta Loudspeaker User Manual

KEF Blade Two Meta Loudspeaker

Product Information

The KALMAN RUBINSON KEF Blade Two Meta is a high-end loudspeaker designed for exceptional audio performance. It is the successor to the previous model, featuring similar dimensions and weight. The loudspeaker is equipped with a single Uni-Q driver on the front, two pairs of force-canceling woofers on the sides, and two large ports for separate woofer chamber venting. The speaker terminals are also identical to the previous model.

One notable difference in the Blade Two Meta is the Uni-Q driver. Unlike the LS50 model, which is a two-way loudspeaker with a tweeter/midwoofer combination, the Blade Two Meta is a three-way loudspeaker with a tweeter/midrange combination. This allows the Uni-Q driver to operate over a narrower bandwidth, resulting in enhanced performance. The Blade Two Meta offers improved audio quality at a slightly higher price point. However, when considering inflation, the new speaker is actually approximately 10% cheaper.

Specifications

• Loudspeaker Model: KALMAN RUBINSON KEF Blade Two Meta
• Uni-Q Driver: Tweeter/Midrange Combination
• Woofer Configuration: Two pairs of force-canceling woofers
• Ports: Two large ports for separate woofer chamber venting

Product Usage Instructions

1. Placement: Find a suitable location for the loudspeakers where they can be positioned at ear level and have sufficient space around them for optimal sound dispersion.
2. Connectivity: Use high-quality speaker cables to connect the loudspeakers to your audio system. Ensure the positive and negative terminals match correctly.
3. Power On: Turn on your audio system and set the volume to a moderate level.
4. Audio Source: Connect your desired audio source, such as a CD player or amplifier, to the input of your audio system.
5. Listening Experience: Sit back and enjoy the high-quality audio reproduction provided by the KALMAN RUBINSON KEF Blade Two Meta loudspeakers.

Instruction

It seems as if I have been waiting for these all my life. Not in any existential sense, but in a literal, practical way: The ar-rival of the Blade Two Meta is the culmination of a lifelong fascination with KEF. As a teenager, I was introduced to founder Raymond Cooke and his innovative “race-track” woofer, Mylar tweeter, and Bextrene cones in Bud Fried’s IMF Newsletter. Shortly thereafter, I commenced decades of building loudspeakers, mostly with KEF drivers, and, beginning with the 104 in 1973, pining for their Reference speakers. They always seemed to strike the right balance of intelligent engineering, solid construction, and domestic suitability. Regrettably, they were always priced out of my reach.

The project Cooke started has been sustained by a succession of notable designers and engineers (Laurie Fincham; Andrew Jones), and it seems to be flourishing under the current VP of technology, Jack Oclee-Brown. During his tenure, we have seen the matura-tion and refinement of the Uni-Q coaxial driver, the development and implementation of Metamaterial Absorption Technology (MAT), the use of force-canceling woofers to minimize cabinet vibration and coloration, and the introduction of stiff, glass-reinforced composite cabinet material shaped to reduce diffrac-tion. These technologies and others combine in what KEF calls a “Single Apparent Source.” All are incorporated in the new Blade Meta speakers.

When the original Blade was released in 2009, I was fascinated but also intimidated. They looked like no other speaker, and they were tall. The latter is significant because I enjoy the view from my Manhattan apartment, unobstructed on the inside, at least. Still, I was jealous when John Atkinson reviewed the smaller Blade Two in 2015.1 This time, anticipating updates to the Blades (and the Reference line) for KEF’s 60th birthday, I presumptu-ously requested a pair of the new Blade Twos well before they were announced. It worked.

Superficially, the Blade Two Meta looks just like its predecessor: same shape, same dimensions, same weight, a single Uni-Q driver on the front, two pairs of force-canceling woofers mounted on the cabinet’s two sides, and two large ports, each venting a separate chamber for each woofer pair. Even the speaker terminals look the same. Yes, the price is higher, but taking inflation into account, the new speaker is actually about 10% cheaper. So, what’s new in 2022? Uni-Q, KEF’s unique, concentric tweeter/midrange driver, is now in its 12th generation; as the “Meta” name indicates, it incorporates Metamaterial Absorption Technology (MAT) to reduce the influence of the reflection of the tweeter’s backwave back onto its own diaphragm. This 12th generation technology has already appeared in the LS50 Meta, and John Atkinson said that in comparing it to its predecessor, it “improves on its presentation of low- level detail and … presents a more transparent window into the recorded soundstage.”2

The Uni-Q in the Blade Two is a bit different. The LS50 is a two-way loudspeaker, its Uni-Q is a tweeter/midwoofer com-bination, while in the three-way Blade, the Uni-Q is a tweeter/midrange combination, so it’s free to operate over a narrower bandwidth.

The Meta Uni-Q’s midrange also operates over a narrower bandwidth than the Uni-Q in the original, crossing over to the woofers at 450Hz and to the tweeter at 2.2kHz, compared to 320Hz and 2.4kHz in the original Blade Two. The increase in the lower-limit frequency should improve power handling. Frequency-response linearity and dispersion control have been enhanced by a redesign of the crossover, which now incorporates a polarity inversion for the midrange. A fascinating and compre-hensive document on the technical development of the Blade and

1. See stereophile.com/content/kef-blade-two-loudspeaker.
2. See JA’s review for a description of the MAT technology at stereophile.com/content/kef-ls50-meta-loudspeaker.

SPECIFICATIONS

Description Three-way “Single Apparent Source” loudspeaker in a bass-reflex enclosure.

• Drive units: one 5″ Uni-Q (coaxial) driver with 1″ alumi-num dome with MAT HF, two 6.5″ aluminum-cone bass drivers in force-canceling configuration.
• Crossover frequencies: 450Hz, 2.2kHz.
• Frequency response: 30Hz–45kHz (–6dB) free field, 33Hz–35kHz (±3dB).
• Typical in-room bass response: 25Hz (–6dB).
• Impedance: 4 ohms (3.2 ohms minimum).
• Sensitivity: 86dB/2.83V/m.
• Recommended amplifier power: 50–400W RMS.
• Maximum output: 116dB (peak SPL @ 1m with pink noise).
• Harmonic distortion (2nd & 3rd harmonics @ 1m, 90dB): <0.5% 40Hz and above, <0.2% 200Hz–2kHz, <0.1% 2kHz–20kHz.
• Dimensions 57.5″ (1461mm) H × 13.3″ (338mm) W × 18.7″ (475mm) D including base.
• Weight: 77.8lb (35.4kg).

Finishes (cabinet/Uni-Q) Piano Black/Copper, Piano Black/Grey, Frosted Blue/Blue, Frosted Blue/Bronze, Charcoal Grey/Red, Charcoal Grey/Bronze, Racing Red/Grey, Arctic White/Champagne. Serial numbers of units reviewed 050943L, 050943R. Manufactured in Maidstone, Kent, UK. disclosed, but speakers are available online from KEF and other resellers.

• Warranty: 5 years.

• Manufacturer
  KEF, GP Acoustics (UK) Ltd., Eccleston Rd., Tovil, Maidstone, Kent ME15 6QP, England, UK. US distributor:

• GP Acoustics (US) Inc.
  10 Timber Ln., Marlboro, NJ 07746.

• Tel: 732-683-2356.

• Web: kef.com.

• Price $28,000/pair. Approxi-mate number of dealers: not

Setting up the Blade Two Metas

Oh, my, these are lovely speakers. Our room style might be described as transitional, with traditional elements and far from modern. Yet, the Brâncu?i-inspired Blades fit right in. Yes, they are tall and deep, but they are so narrow, gracefully shaped, and finished that they do not dominate the space visually no matter where they are placed.

These Charcoal Grey and Bronze Blade Two Metas were trucked in from KEF Ameri- ca in New Jersey and installed by a team head-ed by Ben Hagens, KEF’s product training manager. It was the swiftest installation of a pair of large speakers that I’ve witnessed. The KEF guys knew what they were doing, the packaging was uncomplicated, no assembly was needed, and for all their size, the Blades are relatively light, at 78lb. What’s more, Ben was happy to let me deal with the fine-tuning. We were all standing, behind the sofa where I normally sit while listening. I connected speaker cables to the upper pair of terminals on each Blade and hit Play. The sound that emerged was immediately appealing, so, after exchanging a few stories and anecdotes, Ben and his team took their leave and headed back to NJ, taking the boxes with them.

All this was in stark, welcome contrast to many lengthy, micromanaged installations in the past. When I sat down to listen seriously, I found that the bass from the Blades was un-critical of placement: As long as each Blade remained within the magic 1m circles where almost all speakers end up, the bass was full, deep, and tight. Otherwise, the heard sound was clean and well- balanced but a little bit diffuse: A snapped-in center image was lacking.

Using Scenes in Tin Can Alley, a delightful new recording of piano music by American composer Florence Price performed by Josh Tatsuo Cullen (24/96 download, Blue Griffin), I moved the Blades around their end of the room. They were fine wherever I put them; however, to optimize the initial sense of the acoustical space of Blue Griffin’s Studio, “The Ballroom,” and to solidly place the piano in the center, the Blades needed to sit a few inches farther apart and closer to the wall behind them—farther from the listening position—than my Revel Studio2s did. Like the Studios, they were best toed-in, aimed

KEF offers a comprehensive document on the Blade and Reference technical development. See shop.us.kef.com/pub/media/reference/KEF_Blade_Ref_Meta_Tech_Paper.pdf. The link is a bit wonky, so keep trying if it doesn’t work.

MEASUREMENTS

Iused DRA Labs’ MLSSA system, a calibrated DPA 4006 microphone, and an Earthworks microphone pre-amplifier to measure the KEF Blade Two Meta’s frequency response in the farfield. I used an Earthworks QTC-40 mike for the nearfield measurements. Because I perform the quasi-anechoic response measurements in-room, I usually place a loudspeaker’s tweeter midway between the floor and ceiling, which equalizes the timing of the reflections from those boundaries. But because of the speaker’s bulk, I wasn’t able to lift it as high as I prefer. The pres-ence of an early reflection from the floor of the Uni-Q’s output therefore reduced the anechoic time window I used for FFT analysis, which in turn reduced the farfield response measurements’ resolution in the midrange.

KEF specifies the Blade Two Meta’s voltage sensitivity as 86dB/2.83V/m. My B-weighted estimate was slightly higher, at 86.7dB(B)/2.83V/m. The Blade Two Meta’s impedance is specified as 4 ohms, with a minimum value of 3.2 ohms. The imped-ance magnitude, measured with Dayton Audio’s DATS V2 system, is shown as the solid trace in fig.1. It varied between 3 ohms and 5 ohms over most of the audioband, with an increase in the low treble to 16 ohms due to the crossover between the Uni-Q’s tweeter and midrange sections. The minimum-magnitude saddle of 2.8 ohms at 37Hz in the magnitude trace reveals that this is the tuning frequency of the twin ports on the rear panel.

The electrical phase angle (dotted trace) is generally benign, but the effective resistance, or EPDR,1 lies below 2 ohms be-tween 30Hz and 39Hz and between 813Hz and 881Hz, and below 3 ohms between 3.9kHz and 14kHz. With minimum EPDR values of 1.23 ohms at 34Hz and 1.64 ohms between 813Hz and 881Hz, the Blade Two Meta presents amplifiers with a somewhat demanding load.

I investigated the enclosure’s vibrational behavior with a plastic-tape accelerometer. Although the sidewalls emitted an audible “bonk” when I rapped them with my knuck-les, especially in the region behind the twin woofers, I didn’t find any significant

Fig.1 KEF Blade Two Meta, electrical impedance (solid) and phase (dashed; 2 ohms/vertical div.).

EPDR is the resistive load that gives rise to the same peak dissipation in an amplifier’s output devices as the loudspeaker. See “Audio Power Amplifiers for Loud- speaker Loads,” JAES, Vol.42 No.9, September 1994, and stereophile.com/reference/707heavy/index.html.

Fig.2 KEF Blade Two Meta, cumulative spectral-decay plot calculated from output of accelerometer fastened to center of front baffle below Uni-Q drive unit (MLS driv- ing voltage to speaker, 7.55V; measurement bandwidth, 2kHz).

Directly at the listening position. Now, from the listening position, I was able to enjoy the well-defined image of the piano as Cullen romped through Price’s often bluesy melodies, the ambience spread wide and deep but with little echo to obscure the music’s delicacy.

Listening

Once I had the setup I wanted, I switched to Gottlieb Wallisch’s set of four (so far) discs 20th Century Foxtrots. I had acquired the first volume (16/44.1 download, Grand Piano) out of curiosity, immediately became addicted, and grabbed the three (so far) succeeding is-sues as soon as they appeared.

Sure, these are foxtrots, most of them suit-able for dancing, but they are sophisticated and fascinating. Each disc covers a different geographical area: Austria and the Czech lands; Germany; Central and Eastern Europe; France and Belgium. The composers and arrangers include many great names from the first half of the 20th century—Krenek, Martinu, Hindemith, Gieseking, Weill, Shosta- kovich, Saint-Saëns, Satie, Milhaud, Ravel, Ibert—and many of the pieces are adaptations of music from opera, concert, stage, and film. I loved them so much that I made them the playlist for a recent birthday party. Wallisch is known to me from his marvelous Mozart recordings; he plays a Steinway D in the Jesus-Christus-Kirche, Berlin-Dahlem, a venue that has hosted more than 1500 recordings. The Blade Two Metas justified the Steinway, delivering dynamic range, percussive punch, and treble sparkle that no dancehall piano could approach but that this music deserves. The deep space of the Kirche spans widely beyond the Blades, but Wallisch and the big Steinway seem uncon- strained sitting between them.

I got hooked on Weber’s opera Der Freischütz decades ago when I discovered a marvelously dramatic performance on Electrola LPs, conducted by Joseph Keil- berth and featuring the golden-age voices of Elisabeth Grümmer, Rudolf Schock, Her-mann Prey, and Gottlob Frick. It is available on CD as Warner Classics 9481772. Since then, I’ve added several more recordings of Der Freischütz to my library, including the consensus favorite, conducted brilliantly by Carlos Kleiber with a stellar cast that includes Gundula Janowitz, Peter Schreier, Theo Adam, and Bernd Weikl (2 CDs + Blu-ray, DGG 4838706). Unfortunately, the remastering has not resolved the imbalances between the voices and orchestra; the Keil-berth remains beloved, and more modern resonant modes on these walls. This is a testament to the effectiveness of the Blade Two Meta’s use of opposed and mechani-cally connected woofers on the two side-walls. A couple of modes between 400Hz and 600Hz were present on the front baffle (fig.2), but these modes were very low in level and should not have audible conse-quences.

Fig.3 KEF Blade Two Meta, acoustic crossover on tweeter axis at 50”, corrected for microphone response, with the nearfield response of the midrange unit (green), woof-ers (blue), and ports (red), respectively plotted below 500Hz, 450Hz, and 700Hz.

The red trace in fig.3 shows the response of the ports, measured in the nearfield. (Both ports behaved identically.) The out-put peaks slightly below the tuning frequency, and the upper-frequency rollout is clean, other than a couple of low-level peaks in the midrange. Both the low level and the fact that the ports face to the speaker’s rear will minimize the audibility of this behavior. The four woofers also behaved identically. Their summed nearfield output (fig.3, blue trace) has the expected notch in its output at the tuning frequency of the ports. The woofers’ farfield output crosses over to the midrange section of the Uni-Q driver at 400Hz, slightly and inconsequen-tially lower than the specified frequency of 450Hz. The filter slopes appear to be lower order than those of the original Blade Two,2 but the Uni-Q unit’s farfield response (green trace above 500Hz) is superbly flat and even.

Fig.4 KEF Blade Two Meta, anechoic response on tweeter axis at 50”, averaged across 30° horizontal win-dow and corrected for microphone response, with the complex sum of the nearfield woofer and port responses (black trace below 300Hz).

The complex sum of the woofer and port responses is shown as the black trace below 300Hz in fig.4. The peak at low frequencies will be entirely due to the nearfield measurement technique, which assumes that the drive units are mounted in See fig.3 at stereophile.com/content/kef-blade-two-loudspeaker- measurements.

Fig.5 KEF Blade Two Meta, lateral response family at 50”, normalized to response on tweeter axis, from back to front: differences in response 90°–5° off axis, refer-ence response, differences in response 5°–90° off axis.

recordings (stereo and multichannel) have not challenged my preferences—until now. René Jacobs’s rethinking of Der Freischütz (2 CDs, Harmonia Mundi HMM90270001) is a revelation and not just because of the refresh-ing sounds of the Freiburger Barockorchester, which contrast with the more “classic” orchestras, although there’s that, too. HM’s engineers get everything right, with great clarity and a single acoustic shared by voices (spoken and sung) and the orchestra. Via the Blade Two Metas, I heard lots of delicious detail in the orchestra and impres-sive impact, despite the smaller forces. In the Wolf’s Glen scene, I felt the space close in with the incantations and expand gloriously as chorus, orchestra, and singers approach a climax then fade at the end. I never—not once—thought to myself, “This is great, but it would be even better in multichannel.”

Simon Rattle’s tenure with the London Sym-phony has generated some interesting recordings; none are more impressive than their recent tra-versal of Stravinsky’s big three ballets, The Firebird, Petrushka, and The Rite of Spring (24/96 download, LSO Live LSO5096). These readings are intense and engaging, reminiscent of the young Rattle in Birmingham and among the best- sounding recordings the LSO has produced at the Barbican.4 I started with the Firebird, which begins with an almost subliminal rumbling in the lowest strings. Hearing nothing, I turned up the volume and restarted. Now, those deep, deep murmur-ings, produced by strings but with accents from the lowest winds and brass, were arrayed clearly across a wide, deep stage. Soon came the transi-tion to filling the soundstage with Stravinsky’s colorful orchestration, but the clarity of the instruments remained impressive, especially at the low end. For example, in “Danse Infernale de Tous les Sujets de Kastchei,” the bass drum accentuates the explosive opening and is the pulse of the accelerating dance. Unlike many other recordings (and speakers that reproduce them), which present the bass drum as floor-shaking but of indeterminate size and location, the Blades place it clearly at the left rear of the orchestra. None of its power is lost.

A spacious, transparent soundstage that integrates well-defined bass is a hallmark of the Blade. From the kickdrums and acoustic bass on Jane Ira Bloom’s “Song Patrol,” from Early Americans (24/96 PCM rip from a Sono Luminus Blu-ray, SLE-70005), to Buster Williams’s solos on “Concierto de Aranjuez” from that bassist’s album Griot Libertè (DSD64 rip from High Note SACD HCD 7123) and Jay Bellerose’s drum beat Rattle has announced his departure from London, set to occur in early 2023. An article in the London Times said that one reason for his departure was dissatisfaction with the quality of London’s concert halls and the declining prospect that the city will build a new one. —Jim Austin.

A true infinite baffle, ie, one that extends to infinity in both planes. The woofers’ reflex alignment is maximally flat. The black trace above 300Hz in fig.4 shows the Blade Two Meta’s quasi-anechoic farfield response, averaged across a 30° horizontal window centered on the tweeter axis. The astonish-ingly even on-axis response—even flatter than that of the original Blade Two—is maintained over this wide measurement window. Fig.5 shows the Blade Two Meta’s horizontal dispersion, normalized to the response on the tweeter axis, which thus appears as a straight line. The contour lines Fig.6 KEF Blade Two Meta, vertical response family at 50″, normalized to response on tweeter axis, from back to front: differences in response 15°–5° above axis, reference response, differences in response 5°–10° below axis.

In this graph are commendably even up to 80° off-axis, when the higher- frequency output from the side-mounted woofers in-troduces some irrelevant unevenness. The KEF’s vertical dispersion is shown in fig.6. The tweeter-axis response is maintained over a wide window. Turning to the time domain, the Blade Two Meta’s step response (fig.7) indicates that the tweeter and midrange sections of the Uni-Q drive unit are connected in negative acoustic polarity, the woofers in positive polarity. The decay of the tweeter’s step, which arrives first at the microphone, blends smoothly with the start of the midrange step; its decay in turn smoothly blends with the start of the woofers’ step. This, together with the different distances of each unit’s acoustic center from the microphone, implies optimal crossover implementation. The Blade Two Meta’s cu-mulative spectral-decay plot on the tweeter axis (fig.8) is superbly clean.

Fig.7 KEF Blade Two Meta, step response on tweeter axis at 50″ (5ms time window, 30kHz bandwidth).

I’ve come to expect superb measured performance from Jack Oclee-Brown3 and his team at KEF, and the Blade Two Meta delivered. This is modern loudspeaker engineering at its best.—John Atkinson

See stereophile.com/content/kefs-jack-oclee-brown-talks- loudspeakers.

Fig.8 KEF Blade Two Meta, cumulative spectral-decay plot on tweeter axis at 50″ (0.15ms risetime).

On “Sister Rosetta Goes Before Us” from Robert Plant and Alison Krauss’s Raising Sand (16/44.1 download, Rounder), I hear them all with great clarity and presence with the Blades. The most impressive experience I had with the Blades was with Bob Belden’s kaleidoscopic 12-part symphonic suite, Black Dahlia (DSD64 rip from Blue Note SACD 72435417452). Released in 2001, Black Dahlia was inspired by a brutal, unsolved murder in a very noir 1947 Los Angeles, which has inspired, in addition to this musical work, two novels and a movie. Freed from the literal, Belden’s musical account is almost purely emotive. As the first an-guished chord burst from the Blades, the spell is cast. Belden guides us through these dark, bluesy, brass-driven pieces with fascinating melodies, Latin-inspired rhythms, and brilliant scoring. The Blades’ expansive view went well beyond immersive. It was transporting. Play it loud to complete the illusion and be consumed by the music.

So far, I’ve offered no criticism of the Blade Two Metas’ performance, but lurking in the back of my mind is John Atkin-son’s observation about the original Blade Two: “In my relatively modest-sized room (greatest dimensions: 27′ long by 16.5′ wide), the Blade Twos’ low frequencies were too generous in absolute terms.” My room is slightly smaller than his, nominally 24′ long by 14.5′ wide, but it’s open to two adjacent spaces yielding a total volume that’s comparable to John’s.

Was the Meta’s bass overgen-erous in my space?
With the familiar “First Tears” by Eriks Esenvalds, from The Doors of Heaven (24/88.2 PCM download, Naxos), performed by the Portland State Chamber Choir under Ethan Sperry (and re-corded by John Atkinson), I heard and appreciated more differen-tiation of individual voices as well as a clearer distinction between those voices and the hall. But I heard no difference in tonal bal- ance. Listening with the Blades to a new recording of Beethoven’s Sonatas for Violin and Piano, Nos. 1, 5, and 10 from Rachel Podger and Christopher Glynn (DSD256 download of Channel Clas-sics CCS SA 44222), I found Podger’s violin and Glynn’s Erard fortepiano to be sweet and warm—uncharacteristically warm but the warmth is on the recording. These performances, which verge on romantic, were ideally balanced in the acoustic of St. John’s Church, Upper Norwood.

However, there were indications elsewhere of an excess of bass. Asked to choose between two modern recordings of Fauré’s Requiem—Lawrence Equilbey’s with Accentus and L’Orchestre National De France (CD, Naive V5137) and Mathieu Romano’s with Ensemble Aedes and Les Siècles (24/96 FLAC download, Aparté AP201)—I waffle. I love Romano’s pacing and the acoustics of his space, but Equilbey’s ensemble is richer as, especially, are the organ tones which are the foundation of several sections. Listen-ing to these recordings on the Blades, I was stunned. For the first time, Romano’s opening chord was firmly supported by a deep pedal tone that was distinct from the low tones of the orchestra, and the chorus enters with air and satisfying weight. Switching to the Equilbey, the Blades revealed the organ as excessively powerful, out of keeping with the delicacy of the Requiem—more Saint-Saëns than Fauré—and that impression carried through the piece. Imme-diately, my preference shifted to the Romano. Later I had second thoughts. Still waffling.

On Nils Lofgren’s introduction to “Keith Don’t Go,” from Acoustic Live (16/44.1 FLAC stream, Vision Music/Qobuz), the lower tones and the spiky upper tones are well-known for their richness and presence. When first played on the Blades, at my usual volume setting, I was stunned at how much larger and riper it sounded. Backing the volume down 2–3dB pulled the guitar down to life-sized while keeping it in good balance with the vocals. Here, as in the Fauré, I will say (with apologies to the great Mae West): A bit too much of a good thing can be wonderful.

ASSOCIATED EQUIPMENT

• Digital sources Oppo Digital UDP-105 universal disc player, Custom Intel/Win11 music server running JRiver Media Center v29 and Roon, exaSound s88 Mark II, and Okto DAC8 Pro D/A processors. QNAP TVS-873 NAS.

• Preamplifiers 3 Topping Pre90 preamps for buffer/line drivers.

• Power amplifiers Benchmark AHB2, NAD C 298.

• Loudspeakers Revel Ultima2 Studio with IsoAcoustics Gaia I isolation feet. Revel Performa3 f206. SVS SB-3000 subwoofer.

• Cables Digital: AudioQuest Coffee (USB). Analog interconnects:
  Benchmark Studio&Stage XLR-XLR, Kubala-Sosna Anticipation (RCA), Cardas Cross (subwoofers). Speaker: Benchmark Studio&Stage, Blue Jeans Canare 4S11. AC: SignalCable MagicPower 20A.

• Accessories AudioQuest Niagara 5000, Brick-Wall BrickWall 8RAUD, and CyberPower 850PFCLCD UPS power conditioners, Teddy Pardo 12V PS (for exaSound s88), HDPLEX 300W Linear Power Supply and AC filter (for server).

• Listening room 24′ L × 14′ W × 8′ H, furnished with 2 MSR
  Acoustics Dimension4 SpringTraps in the front corners. Sidewalls lateral to L/R speakers have 2″ thick, 2′ wide floor-to-ceiling OC 705 panels. Front wall has large windows partly covered by fabric drapes and 4″ thick 2′ × 4′ OC 705 panels. Rear of room opens into 10′ × 7′ foyer and a 12′ × 8′ dining area.—Kalman Rubinson

Reflections and comparisons

I compared the Blade Two Meta with my Revel Studio2 with an A/B switch box. I found that if I stood directly in front of a Blade Two or a Studio2 and switched from one to the other, they sounded almost exactly the same. So I measured their frequency responses on axis from the same 1m distance and found that, above about 200Hz, they were both flat and matched each other to within ±2dB. Below 200Hz, they varied more. When I stepped back and sat in my listening seat, things were quite different. In normal listening, even with the speakers aimed directly at the listening position, the bulk of the energy that reaches listeners’ ears is reflected sound, but the amount and spectral character of the reflected sound depends on the speaker’s dispersion. When, sitting in my usual location, I switched from the Blades to the Studio2s, the latter seemed more forward. The treble was emphasized, and the bass was fuller but not as deep.

When I switched from the Studio2s to the Blades, the latter at first seemed a bit more distant but also more spacious, and the Blade’s upper bass was less prominent while its low bass was firmly defined. That said, these differences were not huge. When I turned on the system each day, not remembering which speakers were in use, I sometimes guessed wrong. I had to walk over and look at the switch to be sure, or just sit and listen longer; eventually, those identifying characteristics emerged.

Conclusions

The Blade Two Metas are consistently rewarding and satisfying and gave me great pleasure with all the recordings I played. They offer a remarkably open, transparent, coherent soundstage and taut, extended bass. Are they flawless? That would be a strong claim, but I have not yet found a flaw. In sum, as of today, the Blade Two Metas are the best speak-ers I’ve heard in this room (or perhaps anywhere), and I urge an audition to anyone interested in music reproduction of the highest quality. The Blades were picked up about 24 hours ago, and I miss them already.

stereophile.com | September 2022.

References

• KEF US | KEF USA
• Home Page | Stereophile.com
• KEF Blade Two loudspeaker | Stereophile.com
• Heavy Load: How Loudspeakers Torture Amplifiers | Stereophile.com

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