Issue link: https://digital.copcomm.com/i/78511
Vital Stats: Blue Sky eXo2 (www.abluesky.com/products/exo2-new) Cost: $499 for two monitors, plus an 8" subwoofer and desktop remote control Two-way satellites with 35W per satellite + 90W subwoofer amplifiers 1" tweeter, 3" midwoofer, 8" subwoofer Dimensions: (H x W x D): Satellite: 7.2" x 5" x 4.8"; subwoofer: 9.4" x 9" x 10.2" Weight: Satellite: 3lbs each; subwoofer: 20lbs Frequency response: Satellite: 20kHz – 140Hz; subwoofer: 140Hz – 35Hz Passive crossover frequency for tweeter at 2.2kHz as well as draws power from the converter in the sub enclosure to power the headphone preamp and stereo input on the remote. The two knobs on the front of the remote control the overall system gain, and the subwoofer level as it relates to the overall system output. The interesting thing to note about the satellites is the low fre- quency crossover is fixed at 140Hz, which seems a bit high. All bass information from 140Hz and below is being sent to the subwoofer. In other typical systems with a subwoofer, a low frequency crossover is more likely 80Hz or 60Hz. Another observation is that the sub- woofer enclosure houses the satellites power amps, making it difficult (or maybe even impossible) to expand the system beyond the 2.1 set-up. How can you add more satellites without adding another subwoofer to power the satellites? With those notes aside, the Blue Sky eXo2 does have some advantages. The compact, lightweight design allows the user to easily set up the satellites to be in the optimal listening position (in the stereo triangle, level with your ears). Also, for such a small subwoofer, it delivers a low frequency response of 35Hz. Including the satellites, the overall system has a wide frequency response, up to 20kHz. The Blue Sky eXo2 system has been popular with prosumers as a desktop monitoring system, but with Blue Sky reputation for precise playback and overall sound quality has probably helped to generate inter- est in this set-up among the pro crowd as well. If you're looking for a super-compact system with surprisingly wide and accurate frequency response, then the eXo2 should definitely be on your list. Vital Stats: Adam A7X: (www.adam-audio.com/en/content/a7x) Cost: $699 each Two-way bi-amplified monitor with 50W + 100W RMS amplifiers 2" tweeter, 7" woofer Dimensions: (H x W x D): 13.5" x 8" x 11" Weight: 20.3lbs Frequency response: 42Hz – 50kHz Crossover frequency: At 2.5kHz Max SPL: 114dB Adam Professional Audio was founded in 1999 after Klaus Heinz, physicist and co-founder, perfected a new tweeter design he'd been working on for decades. Adam claims the Accelerating Ribbon Technology (ART) of the new tweeter makes their tweeter more efficient, with better dispersion and less distortion than other typical 1-inch dome tweeters. Building on that technology, Adam created the X-ART tweeter, which has an extended frequency range, up to 46 Post • August 2012 www.postmagazine.com 50kHz, and is even more efficient. They also created their own A/B class amplifier to power it. Though the Adam A7X has been out for a few years now, it's defi- nitely worth checking out. The tweeter design is very interesting and breaks away from the typical coil design everyone else uses. There's an in-depth explanation on the Adam site (www.adam-audio.com/ en/technology/x-art), but I'll try to simplify the process here. The X-ART design uses a pleated piece of foil that expands and contracts, like an accordion, to move air faster than the folds themselves are moving. Also, unlike a traditional cone or dome shape, where the active acoustical area is only 1-inch, the folded foil allows for more surface area, and thus more acoustically active area, in the same amount of space. This gives the X-ART design a higher dynamic out- put and wider dispersion than a traditional dome tweeter. Adam uses a Class D amplifier, or what they call a PWM (Pulse Width Modulation), to power the woofer. According to their site, this type of amp converts the incoming signal into a series of rectangular waveforms of equal height. The amp is more like a binary switch; it is either fully on or fully off. There is no time lost transitioning between the two states. The width of the waveform, and its relation to the other waveforms, represent the musical signal. The result is a system that is extremely efficient and produces less heat. Powering the new tweeter was another challenge for Adam. A PWM amp uses a rectangular wave, but only the low-frequency portion of the wave is the actual audio band. The high-frequency portion just acts as a switch that turns the amp on and off. So a low-pass filer is used to remove the unwanted high-frequency portion. This makes it unsuitable to power the tweeter, which is, of course, all high-frequency information. So Adam created its own high-frequency, class A/B power amp to match the potential of the X-ART tweeter technology. On the rear panel you'll find both XLR and RCA inputs. There is also a gain control (+/-4dB) for the high frequencies. The High Shelf, at 5kHz, and the Low Shelf, at 300Hz, are adjustable by +/-6dB. On the front, there is a power switch and a volume control knob. ACTIVE 3-WAY (MID) NEAR-FIELD If you're looking for something a little bigger than 2-way desktop monitors, here are a few new 3-way options. Focal-JMLab started in 1979 in Saint Etienne, France. Initially they created raw driver units for high-end loudspeakers, as well as home audio products. They later expanded into auto and professional audio products. The new Focal SM9 is a good transition monitor, because it's both a 2-way monitor and a 3-way at the same time. You can switch between the two modes using the "Focus" switch on the side. As a full-range monitor in 3-way mode, the frequency response is 30Hz to 40kHz (+/-3dB), of course the 2-way mode (which deactivates the 8-inch woofer) is more limited, 90Hz–20kHz, to allow the user to