Walter Liederman of Emerald Physics and Underwood HiFi (who were proudly sponsoring the PTA crew here at AXPONA) was on hand to expound the joys and glories of DSP-based audio reproduction and a new wonder-DAC company that he’s importing for US consumers called Exogal.
Emerald Physics has been suggesting, for several years now, that we really need to explore open-baffle speakers. Shown here, the EP-4.8 ($8,495/pair) is a “controlled dispersion” speaker, which means “less room interaction”, and therefore, better in-room sound — regardless of the room in question.

Perhaps a bit unusual for EP, this 4.8 is fully capable of being driven “au naturel” — that is, without DSP. Not saying you can’t use an EP DSP-based system, and good things are promised if you do, but if you don’t wanna, you don’t hafta — this one runs with a fully analog crossover. Also in this update, new carbon-fiber dipole drivers now with cast baskets, and a new “Neo Polyester Diaphragm Compression Tweeter”, tucked concentrically into the top-of-the-cabinet driver. This update is 3dB more sensitive than the version it tweaks. It’s also a 6Ω nominal load (and a 3.5Ω min). The demo model carried a nifty custom hand-painted Cocobolo finish — production models will ship with a Natural Macassar Ebony.
Also new in the rack, the Emerald Physics EP200.2SE ($2,995), a fully-balanced 200wpc (into 8Ω, doubling into 4Ω and stable into 2Ω) hybrid digital integrated amplifier with a custom in-house designed analog power supply. Shown here in bright silver, you can also get it in black. A processor loop (for DSP) gets added to two RCA inputs and one XLR input, and yes, it has a remote-control for volume.
The FPGA-based Exogal Comet DAC, which we reviewed last year, fronted the EP electronics. This is a fantastic, futuristic DAC (we gave it an award), and at $3,500, this DAC is the one to beat in the sub $6,000 price point. A special note to US-based buyers — Walter’s US-only web-based retail shop Underwood HiFi has some aggressive offers. Call for more info.
What caught my eye was the little box right on top of the Comet — the Ion Digital Amp. The price for the Ion is targeting $3,000 when it launches in about a month, and will feature a 125wpc output (into 8Ω, doubling into 4). Now, my understanding is that the Ion is a fully digital amplifier, where the digital signal coming out of the Exogal over a proprietary “EXONET” connection (an HDMI cable, actually) is not converted to analog until the output section of the amp. This makes the Comet more of a “signal stabilizer”, an input switch, and a digital volume control than a DAC, but whatevs. Ion will have two external power supply options, one at $250 and another (much beefier) one at $1,500 that I believe can be used to drive both the Ion and the Comet simultaneously.
One of the niftiest things in this room was almost hidden — the new power cords from Core Power Technologies. These power cords, offered at a variety of price points (all below $1,000 each) include a very hefty in-line (and in-cable, via the big ol’ box dead center of the span) power transformer, creating (essentially) a “balanced power” delivery. Why do this? Noise rejection! Available in three models (which dictate the size/capacity of the transformer) based on assumed capacity in watts: Equi=Core 50 ($499), Equi=Core 150 ($599), and Equi=Core 300 ($799).
Sound quality in the Emerald Physics/Exogal room was a little rocky on Friday, but by Sunday, the room was just crushing it. Bass was tight and fast, with all the detail and slam you could ask for. Total price for the system as shown (which also included in the package the DSPeaker Anti-Mode Dual Core 2.0 bass room correction system, for $1,200), was $16,190; Underwood HiFi is packaging the whole kit-and-kaboodle for $11,999.
Most definitely worth checking out.
Since the speaker technology minimizes room effects, what caused the sound difference between Friday and Sunday?
Tweaking?