Polk Audio RM40T Speaker System, Hitachi 42HDT52 Plasma HDTV, Yamaha RX-4600 A/V Receiver, and Yamaha DVD-S2500 DVD Player HT Labs Measures: Yamaha Receiver
Five channels driven continuously into 8-ohm loads:
0.1% distortion at 87.4 watts
1% distortion at 110.8 watts
All channels driven continuously into 8-ohm loads:
0.1% distortion at 47.3 watts
1% distortion at 48.8 watts
Analog frequency response in Pure Direct mode:
+0.11dB at 10 Hz; +0.08 dB at 20 Hz
–0.18 dB at 20 kHz; –1.07 dB at 50 kHz
Analog frequency response with signal processing:
–0.27 dB at 10 Hz; –0.04 dB at 20 Hz
–0.40 dB at 20 kHz; –23.31 dB at 50 kHz
This graph shows that the RX-V4600's left channel, from CD input to speaker output with two channels driving 8-ohm loads, reaches 0.1% distortion at 148.7 watts and 1% distortion at 175.8 watts. Into 4 ohms, the amplifier reaches 0.1% distortion at 230.8 watts and 1% distortion at 274.9 watts.
Response from the multichannel input to the speaker output measures –0.04 dB at 10 Hz, +0.03 dB at 20 Hz, –0.17 dB at 20 kHz, and –1.06 dB at 50 kHz. THD+N from the amplifier was less than 0.012% at 1 kHz when driving 2.83 volts into an 8-ohm load. Crosstalk at 1 kHz driving 2.83 volts into an 8-ohm load was –80.89 dB left to right and –91.57 dB right to left. The signal-to-noise ratio with 2.83 volts driving an 8-ohm load from 10 Hz to 24 kHz with "A" weighting was –99.88 dBrA.
From the Dolby Digital input to the loudspeaker output, the left channel measures –0.00 dB at 20 Hz and –0.45 dB at 20 kHz. The center channel measures –0.05 dB at 20 Hz and –0.27 dB at 20 kHz, and the left surround channel measures –0.10 dB at 20 Hz and –0.31 dB at 20 kHz. From the Dolby Digital input to the line-level output, the LFE channel is +0.11 dB at 20 Hz when referenced to the level at 40 Hz and reaches the upper 3-dB down point at 96 Hz and the upper 6-dB down point at 116 Hz.—MJP