Specifications Audioengine HD6 Specifications: Power output - 150W peak power total (50W RMS, 75W peak per channel) Inputs - 3.5mm mini-jack, RCA L/R, digital optical (SPDIF,) Bluetooth aptX Outputs - Variable line-out w/2.0V RMS max output, 47ohm output impedance Input voltages - ]115/240V, 50/60Hz manually-switchable Amplifier type - Analog dual-class A/B monolithic Drivers - 5.5" Kevlar woofers, 1" silk dome tweeters SNR - >95dB (typical A-weighted) THD+N - <0.05% at all power settings Crosstalk - -50dB Frequency response - 50Hz-22kHz ±1.5dB Analog input impedance - 48Kohms unbalanced (mini-jack and RCA inputs) Protection - Output current limiting, thermal over-temperature, power on/off transient protection, replaceable external main fuse Internal D/A converter - AKM AK4396 Input bit depth - 24-bits upsampled Bluetooth receiver type - Bluetooth 4.0 audio Supported codecs - aptX, AAC, SBC Wireless operation range - Up to 100ft (30m) typical Input data rate - Determined by Bluetooth Wireless latency - ~30 milliseconds (ms) Optical Input bit depth - up to 24-bits native Optical Input data rate - up to 192KS/s native Speaker dimensions (HxWxD) and weight - Left speaker (powered): 11.75” (30cm) x 7.25” (18.5cm) x 10” (25cm), Weight: 17.5 lbs (8kg); Right speaker (passive): 11.75” (30cm) x 7.25” (18.5cm) x 10” (25cm), Weight: 12.5 lbs (5.5kg) Shipping box - Dimensions: 17” (43cm) x 20” (51cm) x 15” (38cm), Total weight: 33.5 lbs (15kg) Power consumption - Idle: 10W, Mute: 6W; Sleep: 4W
My in-room-measured Frequency Response is quite clean, thanks to heavy-duty reflection control, as shown by a 48th-octave smoothed version. Gating the response made no improvement to these measurements. The 6th-octave smoothed version shows a slight rise toward the low frequencies, as one would expect with such an indoor measurement. Response is smooth and extended, and matching between speakers is near-perfect through most of the range, supporting the excellent SS&I performance I experienced with the HD6. Above 5 kHz the matching is less precise but still very good.
I do not claim anechoic measurement quality, so some LF boost and differences from Audioengine’s published claims are inevitable. The point made is that response is smooth and extended and well matched between left and right through the listening range.
Frequency Response Outdoor, another view showing smooth overall response.
Off-axis response remains smooth and is quite respectable clear to 45 degrees.
Harmonic Distortion for this specimen is very low, as shown at 75 dB listening level at 1 m, below 0.4% above 200 Hz, and stays below 1% at 85 dB SPL at 1 m at those frequencies.
Impulse response shows a possible slight tendency toward stored energy in the final settle time.
Step response gives no indication of strong resonances or of troubling overshoots or irregularities.
Measurement Methods Asus G74SX Laptop, Intel I7-2670QM @ 2.2 GHz, 16 GB DDR3 Memory, Windows 7 64-bit, Room EQ Wizard, foobar2000, Reaper DAW Digital Audio Workstation, Phenom II x6 1100t @ 3.5 GHz, 16 GB DDR2 Memory, AMD Radeon HD 6670 Graphics & HDMI Media by Sapphire, Windows 7 64-bit, Room EQ Wizard, foobar2000, Reaper DAW Digital Media Server, Phenom II x6 1055t @ 2.8 GHz, 8 GB DDR2 Memory, AMD Radeon HD 6450 Graphics & HDMI Media by Asus, Windows 7 64-bit, Room EQ Wizard, foobar2000, Reaper DAW Audioengine D1 Premium 24-bit DAC, Courtesy Audioengine Roland Quad-Capture Audio Interface M-Audio Fast Track C600 Audio Interface M-Audio Firewire 410 Audio Interface Beyerdynamic MM1 Measurement Microphone American Recorder SPL-8810 Sound Level Meter OPPO PM-1 Planar-Magnetic Headphones, Courtesy OPPO, Home Theater Shack Sponsor OPPO HA-1 DAC/Headphone Amplifier, Courtesy OPPO, Home Theater Shack Sponsor
Sponsor[/b] Audioengine B1 Wireless Bluetooth 4.0 Music Receiver with aptX Codec ASUS Nexus 7 Tablet (2013 version) LG G3 Smartphone with aptX Codec Axiom ADA-1250 4-Channel Power Amplifier, Courtesy Axiom Audio Behringer A500 Reference Power Amplifier Onkyo TX-SR705 Receiver Emotiva Pro Airmotiv 4 Powered Studio Monitors MartinLogan ESL Hybrid Electrostatic Loudspeakers Polk PSW10 10-Inch 100-Watt Powered Subwoofer Sony SA-WM250 8-Inch 100-Watt Powered Subwoofer Bosch DLR130 Laser Distance Measurer Fluke 77 Multimeter P3 P4400 Kill-A-Watt Electricity Usage Monitor CyberPower PP1100SW Sinewave UPS