All amplifier measurements are performed independently by Warkwyn Associates. All measurement data and graphical information displayed below are the property of the SoundStage! Network and Schneider Publishing Inc. Reproduction in any format is not permitted.
Note: Measurements were made at 120V AC line voltage and through the balanced inputs with both channels driven unless otherwise noted. All measurements made with the Stanford Research Systems SR1 audio analyzer.
Power output
- Output power at 1% THD+N: 90.8W @ 8 ohms, 135.8W @ 4 ohms
Additional data
- This integrated amplifier does not invert polarity.
- AC line current draw: 0.27A, 0.61PF, 20.0W
- Input sensitivity for 1W output into 8 ohms, balanced and unbalanced inputs: 77.4mV
- Input impedance @ 1kHz:
- Unbalanced inputs: 27.3k ohms
- Balanced inputs: 100.7k ohms
- Output impedance at 50Hz: 0.022 ohms
- Gain, output voltage divided by input voltage: 36.56X, 31.26dB
- Output noise, unbalanced inputs, 8-ohm load, 1k-ohm input termination, Lch/Rch
- Volume control at reference position
- wideband: 0.168mV, -84.5dBW / 0.111mV, -88.1dBW
- A weighted: 0.111mV, -88.2dBW / 0.083mV, -90.1dBW
- Volume control full clockwise (maximum)
- wideband: 0.094mV, -89.5dBW / 0.083mV, -90.1dBW
- A weighted: 0.066mV, -92.6dBW / 0.060mV, -93.5dBW
- Volume control full counterclockwise (minimum)
- wideband: 0.080mV, -91.0dBW / 0.080mV, -91.0dBW
- A weighted: 0.057mV, -92.6dBW / 0.060mV, -93.5dBW
- Volume control at reference position
- Output noise, balanced inputs, 8-ohm load, 600-ohm input termination, Lch/Rch
- Volume control at reference position
- wideband: 0.171mV, -84.4dBW / 0.121mV, -87.3dBW
- A weighted: 0.115mV, -87.8dBW / 0.092V, -89.8dBW
- Volume control full clockwise (maximum)
- wideband: 0.150mV, -85.5dBW / 0.151mV, -85.4dBW
- A weighted: 0.115mV, -87.8dBW / 0.117mV, -87.7dBW
- Volume control full counterclockwise (minimum)
- wideband: 0.081mV, -90.9dBW / 0.080mV, -91.0dBW
- A weighted: 0.057mV, -93.7dBW / 0.060mV, -93.5dBW
Measurements summary
The Hegel H80 is a medium-powered, solid-state integrated amplifier with analog and digital inputs. Its 31dB of voltage gain is typical for a modern integrated amplifier. Measurements were performed through the balanced analog inputs and coaxial digital input, as noted.
Chart 1A shows the H80’s frequency response through the analog inputs with varying loads. The close spacing of the lines from 10Hz to nearly 20kHz indicates a low output impedance that will minimally interact with most loudspeakers. In the lowest frequencies, the H80’s output does taper off slightly beginning at about 70Hz, but is down by only 0.5dB at 10Hz. The measurements reveal some load dependence in the upper frequencies, with the open-circuit test flat to nearly 50kHz, the 8-ohm loading down by 0.1dB at 20kHz, and the 4-ohm loading down by 0.2dB at 20kHz, though the latter drops are quite small.
Chart 1B shows the frequency response into varying loads when fed a 24-bit/48kHz signal through the coaxial digital input. As with the analog inputs, the lines are closely spaced, meaning there will be little variation, regardless of load. The lowest frequencies show the same kind of subtle rolloff as through the analog inputs, but all load conditions, even the open circuit, show a slight rolloff of 0.3-0.5dB by 20kHz, likely due to the influence of the antialiasing filter.
Chart 2 shows how total harmonic distortion (THD) plus noise and intermodulation distortion (IMD) vary in relation to power output. THD and IMD levels stay comfortably below 0.05% at output levels short of clipping.
Chart 3A shows distortion in relation to power output and frequency for the balanced analog inputs. Distortion remains below 0.02% from 20Hz to about 12kHz for power-output levels of 1 to 70W, and falls below 0.01% above about 12kHz for those same power levels. Chart 3B is the same test, but with a 24/48 signal fed through the coaxial input of the DAC section. The 1W distortion level is slightly higher than through the analog inputs, but still less than 0.03% throughout the audioband. For higher power levels, the distortion remains below 0.02% from 20Hz to 10kHz, and is less than 0.01% for higher frequencies. (Note that the decrease in distortion above 10kHz in these charts is a result of a 22kHz cutoff filter, which helps to improve the accuracy of this test below 10kHz.)
Chart 4 shows damping factor vs. frequency. The H80’s damping factor is usefully high from about 100Hz to 4kHz. The decrease in damping factor into higher frequencies is typical for a solid-state amplifier, but the rolloff below 100Hz is unusual, and may be related to the H80’s tapering response into lower frequencies seen in Chart 1A. The shape of this curve is similar to that of Hegel’s H20 stereo power amplifier, which was measured in 2011.
Chart 5A shows the spectrum of harmonic distortion and noise residue of a 1kHz test signal at 10W fed through the balanced analog input. A series of power-supply-related harmonics are visible, as are intermodulation components of signal harmonics in line harmonics, but all lie below 0.0001%. The highest signal harmonic is the third, at about 0.002%, with higher-order harmonics visible to beyond 10kHz.
Chart 5B shows the same test with the signal fed through the coaxial digital input. Noise from the power supply is higher than through the analog input, with the second harmonic reaching 0.0017%, but any intermodulation components remain below 0.0001%. With the digital input, the second signal harmonic is the strongest, at about 0.004%, and a long series of higher harmonics are still apparent.
Chart 1 - Frequency response of output voltage as a function of output loading
Chart 1A - balanced analog input
Black line = open circuit
Magenta line = dummy-speaker load
Cyan line = 8-ohm load
Blue line = 4-ohm loadChart 1B - digital input @ 48kHz
Black line = open circuit
Magenta line = dummy-speaker load
Cyan line = 8-ohm load
Blue line = 4-ohm loadChart 2 - Distortion as a function of power output and output loading
(Line up at 10W to determine lines)
Top line (red dashed) = 4-ohm SMPTE IM distortion
Second line (black dashed) = 8-ohm SMPTE IM distortion
Third line (red) = 4-ohm THD+N
Bottom line (black) = 8-ohm THD+NChart 3 - Distortion as a function of power output and frequency
Chart 3A - balanced analog input, 22kHz cutoff filter
(8-ohm loading)
Black line = 1W
Green line = 10W
Blue line = 20W
Red line = 40W
Magenta line = 70WChart 3B - digital (coaxial) input @ 48kHz, 22kHz cutoff filter
(8-ohm loading)
Black line = 1W
Green line = 10W
Blue line = 20W
Red line = 40W
Magent line = 70WChart 4 - Damping factor as a function of frequency
Damping factor = output impedance divided into 8
Chart 5 - Distortion and noise spectrum
Chart 5A - balanced analog input
1kHz signal at 10W into an 8-ohm load
Chart 5B - digital (coaxial) input at 48kHz
1kHz signal at 10W into an 8-ohm load
- Volume control at reference position