Emerald Physics KC II Open Baffle Speaker


Mark Schifter of Emerald Physics contacted me about reviewing the company’s latest loudspeaker, the KCII. Rarely do I receive introductory letters written in so charming a style. 

I have heard and been very impressed by various Emerald Physics models at shows over the past few years. I was struck by the natural sound and dynamics coming from a fairly small standing footprint and with an open rear baffle, boxless design. 

Schifter is a big fan of Magneplanar loudspeaker sound and its unique open baffle design. With the KCIIs, Emerald has attempted to create a refined, powerful sound in their entry level offering. Schifter considers open baffle speakers to ‘present the music without the box colorations of typical speakers.’

The loudspeakers arrived at the office in the basic black finish. The photo above is of the Cocobolo wood upgrade. They look so good, I thought we’d lead with that photo. The basic black powdercoat finish will set you back only $2500, priced directly from the manufacturer.

   The Emerald Physics KCIIs shown in optional black Tri-coat, a $1200.00 upgraded optional finish


The Emerald Physics KCIIs shown in optional black Tri-coat, a $1200.00 upgraded optional finish

The KCIIs are quite heavy. You’ll be better off lifting and setting up with a two person team. They are bi wired, but mine were supplied with jumpers attached so I could use my Antipodes Audio Reference speaker cables. These cables are twice the cost of the speaker, but why not baby good things? And the KCIIs are very good things. 

Four lag screws per speaker later, and they were matched to the bases. Not the tightest fit in the world, but safely engineered with just a little 'give'. 

Setup was very easy. They are designed to comply with rooms and angles of all sizes. But why not fiddle a little? You will get optimum placement. I tried the speakers firing both directly then slightly toed into the room. Both excellent, but I opted for straight out with its slightly broader sound stage. Because of the open baffle, you may want them to be set off the back wall a foot or two. Two feet worked well in our music room. The speakers were played casually for a week before the serious listening began. 

Emerald has made an effort to make these speakers as 'civilian' friendly as possible. 'The KC II is the first under $2500.00 open baffle Emerald Physics speaker that runs with no DSP and can be run with a single amp.' As such, it was plug and play. 

KCII crossover

KCII crossover

The driver placement and choice intrigued me. I asked Schifter to offer a little background information about the driver specifics of the KCII. 

The Godzilla is our 8” coax midrange tweeter. This is a very special driver designed by the Emerald team of Dan Mullins and Mark Schifter and custom built for them.

The tweeter uses an 80 degree “Lens” system and we couple it to the cone itself which acts as a Waveguide of sorts. The idea is carefully “controlled dispersion” that keeps the highs off the walls and in the room. We like to remove the room as much as we can – and this design resource does just that. 

The Aperture Bass Loading forces the driver (woofer) to think there is a larger baffle area than there actually is (which is a good thing for Open Baffle) and it also creates a “mechanical” roll off which we use in conjunction with the electrical roll off designed into the crossover. The actual number is about 300Hz where this occurs.

KCII rear open baffle design

KCII rear open baffle design

The KCIIs can be driven very easily and have a frequency range of 46Hz–22kH. Bass response in my room was emphatic and controlled. My Audio Research VS110 power amplifier was a lovely tubed match. Thomas Newman's title track of American Beauty spoke of resonant bass that was deep and impressive. And while the bass was balanced, I really enjoyed the beautiful midrange. Textures were rich and images were well defined. The multitude of Latin Percussion in the Newman chart was handled with aplomb. The lines can sound muddy if one part of the audio chain is not up to par. 

The KCIIs have fewer add ons which make for ease of use. A good thing and represented in the price. That said, I recognized almost immediately the same open sound with flesh and bones that I've heard on the more expensive Emeralds at shows. 

With no box, the physics, or lack there of has an effect on sound reproduction. But boxes have to get the physics right and add weight where the Emeralds open baffle cannot match. But gains in transparency may well be worth the tradeoff. 

The transparency was beguiling in string quartets, where differences in string school sound were delivered easily by the KCII drivers. The Emeralds allow musical digging this deep. As example, the Paris Conservatoire Ysaye Quartet and Vienna trained Alban Berg Quartet late Beethoven performances could not have been more different -- timbre, vibrato, dynamics. Many speakers will hint at it. The Emeralds love transparency. A tactile aesthetic to which all speakers should strive. 

I threw on Pictures for power. Reiner LSC, of course. Catacombs, in particular. Listening in awe to the huge kinetic rush of the Chicago Symphony scaling up to the trombones/tuba fff was a perfect example of the way the Emeralds project power. Those who fear that a lack of physical structure may reduce impact can rest assured that, as with any good speaker and within reason, the KCIIs will give you are very good representation of what a full symphony orchestra sounds like. 

Handling that, Blues and smoky vocals from Norah Jones were a walk in the very musical park. And voices of both sexes sounded natural in their utterly different environments. Just what you want and expect from top notch, high end kit. Timbal accuracy, vocal and instrumental, is a highlight of these speakers, especially as addressed by the tweeter. 

I'm always excited by good audio design. I'm loving my continued time with the Emerald KCIIs. They offer new glimpses into repertoire daily. A musical stress heretofore unnoticed, a shine on a violin yet unheard. Subtle and rewarding. A musical gift that will keep on giving. And impressing. 

Visually, I'd push the wife for the Cocobolo wood. C'mon, just look at it. Stunning! The charcoal black powdercoat's best attribute is the amazing price point. The KCIIs are also offered in black tricoat. Probably, the cost sweet spot. 

The trickle down technology from the top Emeralds like the EP-2.8s to the new KCII is very effective. You'll get both very sweet and dynamic sound, transparency, a beautifully balanced midrange and a solid low end all for a very reasonable price. Very highly recommended.

Further information: Emerald Physics