WhitakerAudio JC Whitaker 20 W Stereo Integrated Audio Amplifier, Manual, Page: 176 / 196

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WhitakerAudio
7.6.2 Power Amplifier Module
The power amplifier module consists of the right and left channel power amplifiers. Baseline
measurements are listed in Table 7.8. The operating voltages are as follows:
• B+ = +345 V dc
• Bias = –30 V dc
The values shown are for one channel.
Table 7.8 Baseline Performance of Power Amplifier Module
Measurement Conditions Parameter Baseline
Performance
Measurements taken at 1 W power out-
put (2.8 V rms) at speaker terminals
Input voltage 0.30 V rms
Frequency re/–1 dB 7 Hz to 55 kHz
THD 0.5%
IMD (at 2.3 V rms output) 0.35%
Noise unweighted, shorted input termi-
nals
–70 dB
B+ current at 1 W output (1 kHz tone) 65 mA
Measurements taken at 5 W power out-
put (6.3 V rms) at speaker terminals
Input voltage 0.80 V rms
Frequency re/–1 dB 10 Hz to 50 kHz
THD 0.5%
IMD (at 5.1 V rms output) 0.9%
Noise, unweighted, shorted input termi-
nals
–75 dB
B+ current at 5 W output (1 kHz tone) 85 mA
Measurements taken at 10 W power out-
put (8.9 V rms) at speaker terminals
Input voltage 1.0 V rms
Frequency re/–1 dB 15 Hz to 45 kHz
THD 0.9%
IMD (at 7.2 V rms output) 1.75%
Noise, unweighted, shorted input termi-
nals
–80 dB
B+ current at 10 W output (1 kHz tone) 105 mA
Measurements taken at just below
observable clipping point of amplifier at
speaker terminals
Input voltage 1.2 V rms
Output voltage 11.0 V rms
THD at 1 kHz 1.75%
Calculated output power 15.125 W
Noise, unweighted, shorted input termi-
nals
–85 dB
B+ current at just below observable
clipping point of amplifier (1 kHz tone)
120 mA