Expert review and test of the Hegel H-80 Integrated Amplifier and DAC by Australian Hi-Fi Magazine. Free pdf download included.

For very small geographic region, with an even smaller population, Scandinavia is over-represented in the field of high-end audio design and manufacture… particularly the countries of Denmark and Sweden. But Norway isn’t letting the side down, as the Hegel H80 proves.

The Equipment

Like all Hegel’s components, the H80 has very ‘clean’ lines, mostly due to the use of microprocessors for control, so all the control actions required can be accomplished with just the two controls that are positioned either side of the front panel display.

What you can’t do with these two controls is switch the H80 on and off. For that you need to use the power button. Unlike most manufacturers, which put that button around the back on the rear panel of the amplifier, where it’s often either difficult (or impossible) to get to, Hegel has cleverly hidden that control underneath the amplifier, but close enough to the front that you can just poke your finger underneath the left-hand side of the front panel and activate (or de-activate) it.

During power-up, the Hegel H80’s microprocessor runs a start-up check that takes a few dozen seconds, during which time the outputs are muted and the display flashes (the display flashes any time the output is muted, such as if you’ve done it yourself by using the mute button on the remote). Once powered-up, the left side of the front panel display shows the input source you have selected, while the right side of the display shows the volume as a two-digit number. The display is a very nice shade of blue, which works well against the black aluminium of the front panel.



Following the lead of the display, the knob on the left of the display is the input source selector and the one on the right is for volume. Volume can be adjusted between indicated levels of 0 and 99, with the Hegel powering up at whatever volume value you preset (for which a custom remote, not supplied with the unit, is required, about which more later).
The input selector gives you three analogue input options: two unbalanced line inputs and a balanced line input, plus five digital options: two coaxial, two optical and one USB. The coaxial and optical inputs support up to 24/192 and the USB input up to 24/96. The USB input uses a Type B connector and is not asynchronous, because Hegel says that the re-clocking system it uses (apparently similar to the one it uses in its HD11 DAC) does better job of rejecting jitter than do most commercially available asynchronous USB receiver chips. (Hegel uses a Texas Instruments PCM1754 in the H80).

You can control the Hegel H80 by remote, but how much you can do depends on which remote you own. 

The remote that comes standard with the H80 is a low-cost ‘plasticky’ credit-card-sized Chinese-made device powered by a CR2025 button battery (and disappointingly, despite it being supplied separately in a blister pack, the battery supplied with mine turned out to be flat… I had to go out and buy a fresh one) and only controls the basic features of power switching, volume control, input selection and muting (most of the buttons are used to control other Hegel components).

 If you want to use all the Hegel H80’s features, you have to pay extra and buy the Hegel RC8 master remote control. This more complex, better-built remote will allow you to set the start-up volume, set the maximum volume, do factory resets and more.
If you’ve been looking at the photographs of the Hegel H80 that accompany this review and been thinking to yourself that something’s missing, you’d be right. What there isn’t on the front panel is a headphone output… nor is there one located anywhere else on the amplifier. When it comes to the rear panel, what’s missing is a line output, so if you wanted to use a line output to drive a more powerful amplifier… or, more saliently, a headphone amplifier… you can’t.

In Use and Listening Sessions

Setting up the Hegel H80 is a satisfying experience, because all the fittings are of very high quality and the amplifier itself not only looks the part, but also ‘feels’ the part as well, being very weighty and solid.

Listening first to analogue via the balanced inputs I was impressed by the weightiness of the sound of the bass, which is solid and powerful and remained so irrespective of whether I was playing back at background or at ‘set to stun’ levels. This weightiness was not a forwardness or prominence in the bass, just a reassuring solidity, so that every time a kick drum pedal hit the drum-skin, or a double-bassist plucked an open E string, I never had the sense of there being a ‘build-up’ to the sonic event… it just was what it was, and realistically so.


One of the double-bassists I listened to while evaluating the Hegel H80 was none other than Charlie Haden, playing with Keith Jarrett on their 2010 studio album ‘Jasmine’. Although I have long been an admirer of Haden’s oeuvre, I can’t say I’ve ever warmed to Jarrett’s, though I am in awe of his supreme talent. Jasmine, however, sees the two playing standards such as For All We Know, No Moon at All, One Day I’ll Fly Away, Body and Soul and Don’t Ever Leave Me, and for me it just works. I don’t know quite why it works so well—whether it’s because they seem to be having so much fun, or that they’re so in tune with each other’s playing, or that Haden’s immaculate sense of timing keeps Jarrett on a straighter course than he sometimes steers, but this is an album that sounds ‘way more than the sum of its parts and the Hegel H80 delivered the sound of both double-bass and piano as well as I’ve ever heard and in the pauses, the quietness of the amplifier was outstanding. (Indeed the Hegel H80’s quietness and resolution is so good it also reveals Jarrett’s awful vocalise rather more clearly than usual, which I could have done without!)
Midrange sound was excellent. I am listening a lot to The Rose Garden lately: 
‘A Trip through the Garden/The Rose Garden Collection’ is a 26-track compilation of all the material this short-lived but very talented band ever recorded back in the late 60s. It’s the vocals that are the stand-out here, and listening to them via the Hegel H80, it was very easy to hear why The Byrds’ Gene Clark took the band under his wing. Not only are all the individual voices strong, but their harmony singing is superb, particularly that of Diana De Rose and Jim Groshong. Since this Omnivore Records release includes everything they ever recorded, it includes their most famous song, Next Plane to London, which may ring some bells for you if you’re of a certain age.



Switching my listening from the analogue inputs to Hegel’s digital inputs I mostly encored the same listening material, this time being converted from digital by the Hegel H80 and my inescapable conclusion was that this amplifier does a damn’ fine job of it. Its performance may not quite be in the ball-park of the better DACs that are available today, but it’s commensurate with external DACs that you might have considered partnering with the H80 if it didn’t have its own DAC built in already. The only shortcomings are the lack of support on the USB input for sampling frequencies above 96kHz, and that for some reason the USB input on mine couldn’t play 88.2kHz, whereas the coaxial inputs were quite happy to do so (as well as all other sampling rates up to 192kHz).

Conclusion

The fact that the Hegel H80 does not have a headphone output or a line output, plus the lack of 88.2kHz support on USB or 192kHz+ rates on S/PDIF may give potential buyers pause for thought, but if these shortcomings don’t concern you, the Hegel H80 is a powerful, well-built amplifier with an excellent on-board DAC that sounds amazingly good. If you are bothered, take a look at the just-released Hegel H90 Network Streaming integrated amplifier which addresses almost all these issues, adds streaming and wi-fi and, although it’s slightly less powerful, is also slightly lower-priced.  # Henry Blaze

Readers interested in a full technical appraisal of the performance of the Hegel H80 Integrated Amplifier/DAC should continue on and read the LABORATORY REPORT published on the following pages. Readers should note that the results mentioned in the report, tabulated in performance charts and/or displayed using graphs and/or photographs should be construed as applying only to the specific sample tested.

Laboratory Test Report

Hegel rates the output of the H80 with an output of 75-watts per channel, both channels driven into 8Ω and this is exactly what Newport Test Labs measured on its test bench, and it measured this output right across the audio spectrum from 20Hz to 20kHz. This is obviously a good result, but it’s also one that shows that Hegel has such confidence in its manufacturing and quality control procedures that it doesn’t feel the need to build a little ‘headroom’ into the specification to cope with model-to-model variations.

Hegel doesn’t specify the H80’s output into 4Ω loads, but you can see from the tabulated results that Newport Test Labs measured the output of the review sample as 110-watts per channel at 20Hz, 114-watts per channel at 1kHz and 106-watts per channel at 20kHz (all measurements with both channels driven). This isn’t even close to the results I would have expected to see (theoretically an amplifier will double its output when load resistance is halved) of around 150-watts per channel. This indicated to me that Hegel might be using current-limiting circuitry, which was proved when the lab tested the amplifier into 2Ω loads, because that circuitry limited the Hegel H80’s output to 25-watts into 2Ω.



Distortion at an output of one watt is shown in Graphs 1 and 2 into 8Ω and 4Ω loads respectively. You can see the Hegel H80’s distortion was low with both load values, but lower with the 8Ω load. Into 8Ω, the second harmonic distortion component was at –92dB (0.0025%), the third at –100dB (0.001%), the fourth at –102dB (0.0007%), the fifth at –105dB (0.0005%), and the sixth at –109dB (0.0003%). Seventh, eighth and nine harmonic components are visible, but all are around –112dB (0.0002%).


Distortion increased significantly at rated output into both 8Ω and 4Ω loads, as you can see from Graphs 3 and 4. In this case, distortion into 4Ω is slightly lower because Newport Test Labs tested at a power level of 75-watts, rather than the Hegel’s maximum output level of 115-watts into 4Ω. Into 8Ω, the second and third-order harmonic distortion components are at around –83dB (0.007%), then the even-order harmonic components are at around –105dB (0.0005%) right across the audio spectrum, and the odd-order harmonic components are at around –95dB to –100dB (0.001%) out to the eighth harmonic, before dropping below –100dB for the higher-order. It’s pretty obvious that the Hegel H80 is operating at the limit of its abilities here, though the overall THD+N is still only a very low 0.006%.


Intermodulation distortion is shown in Graph 5. The first two sidebands at 19kHz and 20kHz are 85dB down (0.0056%) and the others more than 100dB down (0.001%) which is excellent. The regenerated signal at 1kHz is at –88dB (0.0039%).

Newport Test Labs measured the frequency response of the Hegel H80 into both a standard non-inductive test load as well as into a load that simulates that of a two-way stand-mount loudspeaker and found the amplifier’s response into both was exceptionally flat and extended—6Hz to 112kHz ±0.5dB and 4Hz to 181kHz –3dB. That section of the frequency response lying within the audio band is shown in Graph 6. You can see the response into the resistive load (black trace) tracks the 0dB line for the most part while the response into the simulated loudspeaker load diverges only marginally (at around 200Hz and 6kHz). Sonically, this means the Hegel H80 will ‘sound’ the same irrespective of the loudspeakers its driving, which is good, plus it also means it will be able to control back-emf from speakers with large-coned bass drivers.



The Hegel H80’s channel separation was good, and certainly more than required to ensure adequate separation and superb stereo imaging, but it was somewhat less than I am used to seeing, with the amplifier returning results of 70dB at 20Hz and 69dB at 1kHz… and just 61dB at 20kHz.

The signal-to-noise ratios measured by Newport Test Labs were excellent, with the A-weighted results coming in at 89dB A-weighted referred to a one-watt output and 107dB A-weighted referenced to rated output. Even unweighted, the signal-to-noise ratio referred to rated output was 101dB. (These low noise floors are also obvious in the distortion spectrograms.)

Input sensitivity (as shown in the tabulated results) was the same irrespective of whether the lab tested it via the balanced or unbalanced inputs, with the test results coming in as there being 73mV required for a one-watt output and 633mV for rated output. These results put overall amplifier gain at 31.7dB.

Square wave testing confirmed the excellence of the Hegel H80’s frequency response.

The 100Hz square wave oscillogram shows tilt that indicates a non-d.c. response but there is no untoward bending.

The 1kHz oscillogram is near-perfect, looking as if it came straight from the test signal generator, and the 10kHz oscillogram shows only very, very slight rounding on the leading edge.

The oscillogram showing the Hegel H80’s performance into a highly reactive load reveals total stability—almost no overshoot or ringing. Amplifiers that perform like this in tests tend to also be judged as having good sound in subjective tests. This performance would appear to be a direct result of the Hegel’s ‘SoundEngine’ circuit topology, which is the subject of US Patent 6,275,104. The forward to this patent says one of the failings of conventional amplifiers (that the Hegel circuit addresses) is that: ‘Current kick-back from the connected reactive loads of the amplifier will reach the output of the amplifier. This kick-back will also reach the input stage through the feedback network, and will disturb the operation of the input stage.’

Overall, the Hegel H80 is a very well-designed amplifier that delivered an excellent set of results across all Newport Test Labs’ laboratory tests. #  Steve Holding