The MPEG-4 AAC audio bitstreams above are presented as HTML5 audio objects - which should play back correctly in: This is the bitstream above multiplexed with an explanatory graphic encoded in H.264 Main Profile at 800圆00 resolution. Missing tones in only one channel may indicate a speaker problem. This is at the encoded bitrate of 160 kb/s, at other bitrates the SBR crossover frequency used by the encoder will vary, resulting in more or less tones being heard. If the decoder is only decoding the AAC-LC portion of the bitstream, only the first two tones will be heard. If the decoder supports SBR, all four tones, 6, 8, 10, and 12 KHz should be heard (or seen on a sound level meter if you have high-frequency hearing loss). The LFE signal is encoded 10 dB lower to account for the 10 dB gain in the LFE channel in the playback amplifer's bass management circuits. (Hold SLM next to subwoofer) If full-range speakers are used, the 60 Hz tones should play through each speaker individually, though levels may vary due to standing wave or resonances in the listening rrom. If a subwoofer is used with limited-range main speakers, all 60 Hz tones should play at the same level through the subwoofer. There is a 1 kHz -18 dBFS tone in the center channel throughout.