TEST BENCH
DOLBY DIGITAL PERFORMANCE
All data were obtained from various test DVDs using 16-bit dithered test signals, which set limits on measured distortion and noise performance. Reference input level is –20 dBFS, and reference output is 1 watt into 8 ohms. Volume setting for reference level was 0. All level trims at zero, except for subwoofer-related tests, all speakers were set to “large,” subwoofer on. All are worst-case figures where applicable.
Output at clipping (1 kHz into 8/4 ohms)
1 channel driven: 131/205 W (21.1/23.1 dBW)
5 channels driven (8 ohms): *
7 channels driven (8 ohms): 68 W (18.3 dBW)*
*Protective current-limiting circuits triggered after about 2 seconds of drive of five or more channels at levels higher than approximately 70 watts.
Distortion at 1 watt (THD+N, 1 kHz)
8/4 ohms: 0.03/0.04%
Noise level (A-wtd): –74.3 dB
Excess noise (with sine tone)
16-bit (EN16): 0.3 dB
Frequency response: 20 Hz to 20 kHz +0.1, –0.2 dB
MULTICHANNEL PERFORMANCE, ANALOG INPUT
Reference input and output level is 200 mV; volume setting for reference output level was 2.
Distortion (THD+N, 1 kHz, 8 ohms): 0.04%
Noise level (A-wtd.): –77.9
Frequency response: <10 Hz to 136 kHz +0, –3 dB
STEREO PERFORMANCE, DIGITAL INPUT
Reference level is –20 dBFS; all level trims at zero. Volume setting for reference level was 1.
Output at clipping (1 kHz, 8/4 ohms, both channels driven): 121/190 W (20.8/22.8 dBW)
Distortion at reference level: 0.04%
Linearity error (at –90 dBFS): 0.15 dB
Noise level (A-wtd): –74.0 dB
with signals: –75.8 dB
Excess noise (with/without sine tone)
16-bit (EN16): 0.4/0.5 dB
quasi-20-bit (EN20): 9.5/9.0 dB
Noise modulation: 0.4 dB
Frequency response: <10 Hz to 20 kHz +0, –0.23 dB
with 96-kHz/24-bit signals: <10 Hz to 44.8 kHz +0.2, -3.1 dB
BASS-MANAGEMENT PERFORMANCE
Measured results obtained with Dolby Digital test signals.
Subwoofer-output frequency response (crossover set to 80 Hz): approx. 20 dB/octave above
–6-dB roll-off point of 80 Hz
High-pass-filter frequency response (crossover set to 80 Hz): 12 dB/octave below –3-dB rolloff point of 80 Hz
Maximum unclipped subwoofer output (trim at 0): 7.2v
Crossover consistency: bass crossover frequency and slope were consistent for all sources and formats
Speaker size selection: all channels can be set to “small”
Speaker-distance compensation: available for all main channels.
Sherwood’s latest Newcastle A/V receiver delivered admirable performance from stem to stern. Power output on single- and two-channel tests exceeded spec, and multichannel wattage was in practical terms substantially more generous than our numbers suggest: The stress of all-channels, steady-state tones, which triggered the R-972’s protection circuits on the test bench, is all but unknown in normal listening situations. Noise and D/A linearity were excellent: The Sherwood fell a dB or so short of the best in our real-world S/N tests (this is the sole nit I can find to pick) but its excellent digital-domain behavior, and the fact that noise remained fairly consistent even on 96/24 PCM and analog-input multichannel signals, suggests that the limitations, inconsequential though they are, probably arise in its analog circuits rather than in digital-signal conversion or manipulation.
I grabbed a quick look at the R-972’s Trinnov DSP “target curves,” which corresponded well with Sherwood’s literature. Flat showed the room corrections I would expect to see (they were generally similar to those that Audyssey Dynamic EQ performs on the same room/speakers layout); Audiophile 1 and 2 confine correction to the bass octaves only, with the distinction that Audiophile 2 adds a very mild additional boost through the “warmth” octaves; Natural echoed the Flat curve, with the addition of Audiophile 2’s warmth boost, plus a very mild down-tilt (perhaps 1.5 dB/octave) over the top three octaves.
