Sound On Sound's Bob Thomas adds a Core Sub to Core 47 three-way monitors to explore that additional dimension in the low end...
"Running on its own, the Core Sub felt to me to be totally in control across its full range of 15 to 165 Hz (±3dB). The combination of its four 9-inch woofers and twin 500W amplifiers displays a grasp of transients and speed that reflects their sheer power. On the down side, listening to a solo sub is not a lot of fun, so I switched in the 80Hz filters on the Sub and both Core 47s, set them all to 88dB SPL, and ran through my test CDs again.
What came to the fore instantly was the seamless integration and tonal balance between the Core 47 and the Core Sub. The Sub filled out the bottom octave in a tonally neutral fashion overall. Switching the Sub out and resetting the Core 47s' high–pass filters back to full range did absolutely nothing to alter the overall tonal balance in the soundfield, other than to take out the lowest octave. With the bottom two octaves (80 to 20 Hz) being handled by the Sub, the Core 47's 7-inch woofer is freed to concentrate on the 80 to 475 Hz range, the combination delivering what felt to me to be a slightly more relaxed overall listening experience, compared to the Core 47 on its own.
Cantus's superbly recorded Spes album is another stringent test of an active monitor's abilities. Its soaring female choral voices contrast with Frode Fjellheim's gruff male lead vocal and electronic keyboard, all joined together in a huge church space where reverb tails fade slowly as they linger in its reverberant void. Successfully recreating that soundscape requires not only power, but also precision, delicacy, transparency and a grasp of low-level transient detail.
The Core 47/Core Sub 2.1 setup handled the recreation with ease. The soundstage delivered was wide and nuanced, with a rock-solid phantom centre image and a sense of depth that placed the voices, keyboards and reverbs precisely in place — a most impressive performance.
The combination of their powerful amplifiers, a shared DSP system, mid–range and bass drivers custom-designed for the series, and the superb Esotar Pro tweeter underpins the stunning performance of the Core 47 and the Sub. Perhaps the most impressive part of the Core 47 and Sub setup was its ability to resolve extreme low–frequency detail, and it does so in a way that has been delivered by only one other loudspeaker of my personal acquaintance.
Before starting this review, I had not had the opportunity of working with a true four-way system of this standard. If I had the space and the wherewithal, I'd stack a Core 47 and a Sub on either side of my mixing console and see out my career with that combination."
