I measured the KEF Q900's frequency response in the farfield with DRA Labs' MLSSA system and a calibrated DPA 4006 microphone. The Q900's voltage sensitivity is specified as 91dB/2.83V/m. My estimate was slightly lower, at 90dB(B)/2.83V/m, but this is still usefully higher than average. The speaker's impedance is specified as 8 ohms, but as fig.1 shows, the impedance drops to 4 ohms in the top octaves and to below 4 ohms in the lower midrange, reaching a minimum value of 3.17 ohms at 160Hz. There is also a combination of 5 ohms magnitude and –42° electrical phase…
search
John Atkinson nudged my ribs with an elbow. "Did you bring your Cornelius CD with you?" he whispered.
It was the 2010 Consumer Electronics Show, and JA and I were nearing the end of a dog-and-pony act expertly presented by Atlantic Technology's president, Peter Tribeman, touting a prototype of his company's new loudspeaker, the AT-1. JA and I had just heard about the finer points of the AT-1's new bass-venting technology, the Hybrid-Pressure Acceleration System (H-PAS), which was supposed to combine all the benefits and qualities of a transmission-line enclosure, horn loading, and sealed…
To address these problems, Atlantic has modified the AT-1's tweeter in some important ways. Steve Feinstein: "The tweeter's diaphragm breathes into a rear chamber. This lowers the tweeter's resonance from around 1800Hz to about 900Hz. Next, the entire rear chamber is made from drawn aluminum, which acts as one huge heatsink with lots of surface area, to cool the tweeter really well. Finally, the tweeter's surround is a full 4mm [wide], which is akin to a small woofer having one of those really big surrounds. It lets the tweeter have good, long excursion for low distortion, with no danger of…
Sidebar 1: Specifications
Description: Two-way, floorstanding loudspeaker with H-PAS woofer loading. Drive-units: 1.1" (28mm) silk-dome tweeter, two 5.25" (135mm) graphite-loaded homopolymer-cone (GLH) woofers. Crossover frequency: 2kHz. Crossover type: parallel, second-order low-pass, third-order high-pass. Frequency response: 29Hz–20kHz, ±2dB. Nominal impedance: 6 ohms. Sensitivity: 89dB. Recommended amplification: 20–200W RMS.
Dimensions: 8.85" (227mm) W by 42" (1077mm) H by 13.6" (348mm) D (including grilles and feet). Weight: 54 lbs (24.5kg).
Finish: Gloss black.
Serial…
Sidebar 2: Associated Equipment
Digital Sources: Theta Miles (via S/PDIF output), Bel Canto CD2 CD players; Benchmark DAC1 & DAC1 HDR, Bel Canto DAC3.5VB with VB-1 power supply, Weiss DAC202 DACs; Sony Vaio laptop computer.
Power Amplifiers: Rogue Audio M180 monoblocks, Plinius SA-103.
Loudspeakers: Revel Performa F30, Thiel SCS4T.
Cables: Digital: Stereovox HDVX coaxial, Silver Sonic D-110 AES/EBU. Interconnect: Sain Line Systems Pure (balanced). Speaker: Kimber Kable BiFocal X. AC: Sain Line Systems Reference.—Erick Lichte
Sidebar 3: Measurements
I used DRA Labs' MLSSA system and a calibrated DPA 4006 microphone to measure the Atlantic Technology AT-1's behavior in the farfield. For the nearfield measurements, I used an Earthworks QTC-40 microphone. The AT-1's voltage sensitivity is specified as 89dB. My estimate was actually a little higher than that, at 90dB(B)/2.83V/m. However, the AT-1 draws 2W from the amplifier at this voltage level rather than the expected 1W, its impedance (fig.1) averaging 4 ohms rather than the specified 6 ohms. The value of the AT-1's impedance in the treble depends on the…
MBL, the German manufacturer of lavishly constructed high-end gear, has been working hard to reinvigorate their corporate image, strengthening their bonds with existing customers while reconnecting with music enthusiasts in North America. Today the company releases its new corporate video.
Behold:
The buzz was all over the audiophile 'net. "Pioneer has a new bookshelf speaker that's killer for the money!"
Hmm, I thought. Pioneer. Speakers?
To be fair, I've had the Pioneer brand on my mind for well over 30 years. The company was my brand of choice for car-stereo electronics in the 1970s, for Dolby S cassette decks in the '80s, for DVD players in the '90s, and for plasma TVs in the '00s and '10s. I felt a bit guilty that I hadn't focused on the fact that Andrew Jones, the very same design guru who came up with Pioneer's TAD Reference One loudspeaker ($70,000/pair), had had a…
Part of the reason for the SP-BS41-LR's transient realism was its ability to reproduce extended and uncolored high frequencies, and the way the highs seamlessly integrated with the midrange. I found myself searching for jazz recordings that spotlight the dynamic and tonal range of the trumpet. On the title track of Miles Davis's 'Round About Midnight (CD, Columbia CK 40610), his horn was silky and holographic, with just the right amount of metallic bite and long decay. On a mellower note, in the ballad "Tristan's Way," from Liam Sillery's Priorité (CD, OA2 Records 22082), Sillery stretches…
Sidebar 1: Specifications
Description: Two-way, reflex-loaded, stand-mounted loudspeaker. Drive-units: 1" soft-dome tweeter, 5.25" woofer. Crossover frequency: 2.5kHz.
Frequency range: 55Hz–20kHz. Nominal impedance: 6 ohms. Sensitivity: 85dB/2.83V/m. Maximum input power: 130W.
Dimensions: 7.9" (200mm) W by 13.75" (350mm) H by 8.7" (220mm) D. Weight: 10.25 lbs (4.7kg).
Finish: Black vinyl.
Serial Numbers Of Units Reviewed: JFNV00015BUC (both).
Price: $149.99/pair. Approximate number of dealers: >20 (a limited set of overall Pioneer dealers).
Manufacturer: Pioneer…