Wednesday, October 30, 2019

Spatial Audio X3 Open Baffle Loudspeaker Review

Evolutions Of A Restless Audiophile

As we gain experience, and perhaps get to know ourselves better, our senses and tastes evolve. This evolution in tastes is also what drives our upgrade-itus as audiophiles. Once you hear something better, or once you hear something on a familiar recording you've never heard before you can't "un-hear" it, and the urge to upgrade or tweak your existing system sets in.

My tastes as of late have changed significantly in the realm of loudspeakers and amplification. I suppose as a budding audiophile my tastes were driven in a big way by what I could afford, music I listened to, and also what was popular. Today, with my own dedicated listening space, my preferences are driven more by affordability, less by aesthetics (to a degree) and size (also to a degree). When I started out as a young audiophile, slim speakers were in, they were more affordable, and they fit in my apartment.

The First Aha

One of my "Aha" moments occured when I heard a friend's system. He had some speakers rated at about 98dB efficiency, 3 powered, sealed servo-driven subs, and a FirstWatt SIT3 amp. It was mind altering. The sheer, immersive enjoyment of that experience had me pursuing higher efficiency speakers, high quality sealed servo subs, and Class A, zero negative feedback amps.

The Second

My second "Aha" occured when I heard Open Baffle speakers for the first time. I enjoyed the open, boxless sound that made vocals so much more natural. At the same time, I also was able to listen to a servo controlled, open baffle subwoofer. This was the best bass I had ever heard. It loaded the room in a much more natural way than any box sub I had ever heard. The servos helped the 12" woofers start and stop so quickly. I was bitten by the OB (Open Baffle) bug hard.

The Stars Align

So now being firmly on the path of higher efficiency loudspeakers, paired with Class A operation, zero negative feedback amplifier designs I was on a quest. 

Fortunately, I didn't have to search far. Dan Wright was showing his latest product at the 2018 Capital Audiofest, a hybrid integrated amplifier, with a pair of open baffle speakers from Spatial Audio that were rated at 97dB efficient. I purchased the integrated and Spatial X3 speakers for my Studio. The Modwright KWH 225i integrated amplifier is rated at 25 watts Class A, 225 watts Class A/B operation with zero negative feedback. The integrated was essentially Dan's LS100 preamp and KWA100SE power amp in one chassis. The Modwright would be plenty of power, and headroom for the efficient Spatial X3's.

The Modwright KWH-225i Tube Hybrid Integrated Amplifier.

A Primer On Open Baffle Speakers

Before we get into the speaker review, I want to explain some of the unique features of OB (Open Baffle) speakers. An open baffle speaker design is essentially a dipole speaker that places the drivers in a front baffle, but there is no box or enclosure capturing the back wave of the drivers. They are "open" to radiate to the area behind them as well as to the front, obviously. Their advantage is a sound that is very open, and free of any box colorations since there is no box. 

Since there is not a large box, only a baffle, the appearance of the open baffle speaker, even if it has larger drivers, is that they have a slimmer profile. But... That more slender profile, while having great sounding bass due to no box colorations, usually doesn't have much of it. a 15" OB driver, properly implemented, has about as much bass output as a 10-12" woofer in a sealed box. But the quality of the OB bass is better in my opinion. I loads the room more naturally. However, If you are really into deep bass, like below 30hz, and you like plenty of it, you will most likely need subwoofers.

Noteworthy OB Lovers

Siegfried Linkwitz, legendary loudspeaker designer,  had some very nice things to say about open baffle speakers in general. You can read his comments on his Conclusions page at

Nelson Pass of Pass Labs has also had an intense interest in open baffle speaker designs. I feel like I am in good company with my choices. Now on to the review...



IntegratedModwright KWH 225i

Phono StageModwright PH 9.0

Power Conditioning:
Room Treatments

  • 6 x Stillpoints Aperture II's, placed behind the speakers
  • Vicoustic Multifuser DC2 (Ceiling)
  • Vicoustic Diffusor 32 and 64 (side walls)
  • Bybee V2 x 9 spread about the room

The Spatial X3

The Spatial X3 is a 3 way open baffle design. It stands fairly tall at 49". The Stillpoints Ultra 5 I used under them added another 2". They are 18" wide, and 5"deep if you don't include the depth of the stands.

X3, Full Frontal

It utilizes a Hypex Fusion NCore plate amp to power a 15" custom made driver for frequencies 90 Hz and below. For the midbass/midrange, a custom designed 12" driver going up to (I am guessing) about 1k, and for the highs, a horn loaded Air motion transformer. They are rated at 97dB efficiency with an easy to drive 8 ohm impedance. Offloading the more demanding low frequencies to a powered 15" bass driver really opens up one's choices for amplification. Low powered SET amps are definitely a possibility. I was running the X3's for awhile on a Jolida SJ-302A that had been modified for single ended triode output. It had about 15 watts, and could play fairly loud in my 15 x 25' listening space. If one craves more power and volume, the X3's pro audio drivers can certainly handle it.

Back to the speakers. The drivers are thoughtfully wired with Duelund's "tone wire". I like this wire. In fact my speaker cables are made of 3x 16awg Duelund wires per + and - pole, with Bybee Purifiers in line as well. The crossovers use high quality components like Clarity Caps, and they are finished off with WBT binding posts. The whole package is classy and contemporary. The exposed backs of the drivers even look good. Mr. Shaw has an eye for detail and design.

Peeking in-between the baffles, you can spot the crossover network. Note the Clarity Cap.

The "baffle" is actually 2 baffles, one placed behind the other. They serve to add mass, as well as quell the effects of vibrations. The bass and midrange drivers are attached to the front baffle made of a material called UltraLam which has the look of stacked baltic birch plywood on edge. There are spacers separating the front baffle from the second baffle, which appears to be made of MDF and painted a satin black. The HF driver is attached to the rear baffle, as well as the crossover components and the 15" woofer's amp.

Side view of the X3 showing the dual baffles, and cast iron legs.

The speakers are not heavy, as far as Audiophile speakers go. They weigh about 85 pounds each. Not having massive enclosures provides this benefit as well. The Ultralam baffles lend a very cool design aesthetic, and the cast iron stands complete the contemporary look. The X3's are available in 3 different finishes: Natural, Honey, and Nutmeg tints. The Spatial X3's come with a 5-year warranty and are made in Utah.

The front of the AMT driver

The back of the AMT driver

They were shipped via freight together on a pallet. The boxes and packaging they were in were top notch and well thought out. It was super easy unboxing, unpacking, and moving the speakers into the area where they would be placed.


Spatial recommends that the X3 be at least 3' away from the wall behind the speakers. Mine ended up about 60" on center from the wall behind them, and about 8' apart. I toe'd them in a bit to create a singularly connected Right/Center/Left soundstage. I also took the time to level them and adjust the rake angle. The adjustability of the Stillpoints made this very easy. At this location in the room, the bass was even, and the soundstage expanded to fill the room in all dimensions.

Placement is important for any speaker, it took me several attempts at using the Rational method of speaker placement (very similar to Master Set), but this location is the best so far.
Music Used

Dominique Fils-Aime - Nameless
Bill Calahan - Apocalypse
Kenny Burrell - Midnight Blue
Boz Scaggs - Dig
Cream - Royal Albert Hall, London, May 2-3-5-6 2005
Kenny Barron & Mino Cinelu - Swamp Sally
Jimi Hendrix - Valleys of Neptune
Efterklang - Altid Sammen
David Bowie - Blackstar


I let the speakers run 24/7 for about a week before I began listening with the intent of gauging their character. With the X3's in place, broken in, and with the Modwright amp driving them, the sound was... Where do I even start?

Let's start with this. After break in, these speakers running for a few months before writing the review. So during this time I had many different cables, tweaks, power conditioners, and of course a couple amps in there too. The X3's were an absolute window into whatever changes I made. They let me know exactly what was changing.

Dynamics stood out as they would in a live performance. Top to bottom, from the snap of fingers on an acoustic bass, to vocal, piano, and cymbals. Everything had a lively energy to it.

Bass was perhaps amongst the cleanest, fastest and most tonally colorful (when called for) as I have ever heard. It went down to about 30 Hz and was just beautiful. One could more clearly hear not only drum sticks hitting the toms, but the tone and impact of each drum also came through. For some recordings, it was the first time I heard these nuances in them. However, if you like deeper bass, or a more visceral impact you will need good subs. A sealed or open baffle sub would be my recommendation. There are no commercially available open baffle subs, but there are kits. SVS, Rythmik Audio, and Hsu research make some great sealed subs at the sub $1000 level. 2 or 3 of these should do in nearly any room.

Midrange was open, dynamic, textured and let you know of any colorations in the equipment or recording.

The highs were glorious. Capable of going very loud without compression or smearing. They are a very low distortion driver, capable of massive sonic output. They cruised and never appeared to strain or lose their dynamic snap.

Together, they formed a cohesive, immersive listening experience. The Modwright is such a good integrated, and I heard it's capability in a very exciting manner through the X3's. The imaging was some of the most pinpoint I have heard in my system, the soundstage was wrap-around when it was in the recording. I never grew fatigued of the sound. Quite the opposite, I found myself on many occasions stopping whatever activity I was doing (usually working on my laptop) and being magnetically drawn in to whatever music was playing. There may have been dancing and air guitar on frequent occasions....

On Eric Clapton's Stormy Monday, The X3's place you in the audience, in the middle of Royal Albert Hall with the reflected sounds of the amphitheater appearing to emanate from behind you as they should, and the musicians placed on stage with proper scale.

The snare drums are fast, the cymbals smooth, and Eric Clapton's voice with reverb circling the room. You can tell when his mouth moves away from the mic, for instance when he backs away to play his guitar. There is just such a sense of space in this recording. That's why I like it so much.

Dominique Fils-Aime's song "Birds" starts out with a string bass being plucked hard, ending with a dynamic clap of hands. You could literally "feel" the string bass being plucked with no boominess. It was super-natural sounding.

Dominique's vocal was centered, with her backup vocalists behind and outside of her position, nicely layered with no smearing. Ambient effects were floating all around the room, decays gave a sense of a much larger space. This is great music, recorded well, and the X3's kept my attention and were exciting to listen to.

Bill Calahan's title song, Apocalypse, is a simple arrangement highlighting a few instruments and his unique voice. The song starts out very minimalist and slow, with a single guitar in the center.

The reverb on Mr. Calahan's voice gives a sense of width and depth. The piano is way in the back, and Bill's unique voice (which is hard for a speaker to get right) is full, textured and natural sounding. When you finally hear the ringing of the undamped kick drum, you get to enjoy the tonality and ringing of the skin on the drum. The Cymbals that accompany this are a tiny bit harsh, but it's the recording, not the speakers.

Kenny Burrell's Chitlins con Carne is a familiar recording to most of my readers. It has instruments hard-panned left and right. What I listen for is the clues the drums give to the space in the venue. The muted cowbell(or is it the wooden "Beater") echoes in the space when struck.

The saxophone that comes in at about 3:00 also is panned hard right, but you can hear the ambient information stretching across to the left speakers. You can also hear the guitar follow the sax very closely.

Boz Scaggs "Desire" from the album Dig is a great test on several levels. It opens up with a keyboard hook that has nice low end. Then a solo guitar appears, and you can hear the swirling effects that circle about the room.

The main vocal is centered, very textured and well recorded. The backup vocalists are nicely layered, very detailed and textured. The full frequency capabilities of the X3 are nicely revealed in this tune.

Perhaps my favorite recording, the song "Moon Dance" by Kenny Barron & Mino Cinelu of their album Swamp Sally is a great test of dynamics and tone of bass.

This track has a lot of different types of percussion instruments, and opens up with the chiming of a bell, which is difficult for many DAC's to get right. Fortunately the Lumin X1 does a great job of handling the dynamics and overtone frequencies, so do the X3's. This track really shows of the X3's ability to render dynamics with realism, clarity and tonal shadings. The sense of space, with ambient cues and the right to left dynamic craziness of all the instruments incorporated are extremely impressive.

Bleeding Heart off Jimi Hendrix Vallies of Neptune is just fun. It's not a great recording, but not awful either. I just enjoy the song, and love turning it up.

Of course Jimi's guitar sounds incredible, but the driving beat of the song is great as well.

Efterklang was a discovery for me (thanks Roon Radio). The song I chose off of their album Altid Sammen starts off with a synth opening and moves in to a great bass line. This Danish post rock group recording is excellent and unique.

Sung in their native tongue, I have no idea what the lyrics are saying, but the singer's vocal range really shows off how well the X3's do vocals and convey emotion. The synth, bass and vocals are backed by cello. I sat back and let the music wash over and surround me, filling the room once again and creating an immersive experience.

Finally, David Bowie's Blackstar. I chose the song Lazarus. It opens up with a strong bass drum and snare accompanied by a simple guitar melody.

The dynamics of the snare and bass drum kept my attention focused, Bowie's vocals had a little reverb on them, and the dual saxophones added a sense of space. The emotion in Mr. Bowie's vocals were conveyed with richness and texture. It drew me in to the music.


There is no question I like the Spatial X3's. They tick many boxes on my list: High efficiency? check. Outstanding vocals? check. Tone, texture and space? Check, check and check. Dynamics, oh heck yes! Air and space, definitely check. If your gear is up to it, and you take the time to place these speakers properly (it's not difficult, it just takes patience), they will reward you with a dynamic disappearing act that will have you forgetting about everything, being immersed in the joy and emotional connection to the music that great sound can provide. I would have no qualms pairing the Spatial X3's with very expensive gear in the 5 and possibly 6 figure range. I just don't think they would ever be a bottleneck in the performance. They represent what Tweek Geek is all about: finding reasonably priced high performance gear that delivers engagement, immersion and an emotional connection to the music well beyond it's price point.

My only caveat is for those listeners that need strong, occasionally loud bass performance below say 35 Hz. You would need very good sealed or open baffle subs to keep up with the speed and output of the X3. Rythmik Audio, REL, JL Audio, Hsu Research, and SVS have commercially available subs worthy of consideration. My advice though would be to buy 2 of the GR Research open baffle servo sub kits and have someone build them for you, or if you have the skills, build them on your own. They beat all of the others in terms of tonal quality, and their open baffle design is the best match for the X3.

Tweek Geek has the Spatial X3's ready for you to listen to in our studio, along with all of the other gear used to review them. I invite you to make an appointment to listen to them and visit with me the next time you are in the Denver area.