Review: Hegel H390 integrated amplifier – actually a top model

SoundEngine 2

At the heart of Hegel is SoundEngine technology, a technique to eliminate the distortion that occurs during sound amplification. That distortion is always there, because only on paper can an audio signal from a source be amplified without anything being added. In reality, every class AB amplifier will ‘color’ the sound because of this, although a high-end product will (hopefully) do that for much less than a cheap device. The gain components responsible for amplification simply have certain properties and are never really neutral. Designers have, of course, been aware of this problem for a long time, and are employing various techniques to remove that distortion. But usually these are negative feedback techniques that ‘feed’ the distortion observed at the end of the amplifier back to the beginning of the amplification module to subtract it from the audio signal there. The problem is that there is a certain delay in this process, so the signal to remove the distortion doesn’t quite match the distortion that is currently being created. The anti-distortion sound lags slightly behind the audio signal. This causes problems, especially in the time domain. But there are also other issues associated with this approach, such as increased distortion at higher frequencies and high-frequency noise that is picked up through the speaker cables and sent back into the amplifier. so the signal to remove the distortion does not quite match the distortion that is currently being produced. The anti-distortion sound lags slightly behind the audio signal. This causes problems, especially in the time domain. But there are also other issues associated with this approach, such as increased distortion at higher frequencies and high-frequency noise that is picked up through the speaker cables and sent back into the amplifier. so the signal to remove the distortion does not quite match the distortion that is currently being produced. The anti-distortion sound lags slightly behind the audio signal. This causes problems, especially in the time domain. But there are also other issues associated with this approach, such as increased distortion at higher frequencies and high-frequency noise that is picked up through the speaker cables and sent back into the amplifier.

All that Hegel founder Bent Holter wanted to combat. His research that led to the SoundEngine design was also Hegel’s starting point. SoundEngine works with a feedforward system, where an analog computer continuously measures the distortion coming from an amplification module and creates anti-noise that perfectly mirrors the distortion. This anti-noise is then applied to the output so that only the original audio signal remains, without the slightest lag. Hegel compares it to how noise-canceling headphones function, a comparison that actually makes sense. In any case, SoundEngine is why Hegel amps sound so incredibly tight and fast. The things that make certain rival amps sound sluggish and less accurate are absent here. An additional advantage of the Hegel architecture is that amplifiers like the H390 dampen enormously. The damping factor of 4,000:1 ensures that speakers vibrate less and therefore sound more accurate.

(Almost) Roon Ready

Under the hood of the H390 is fascinating technology, but what makes Hegel all the more captivating is their fresh, modern take on what an amplifier should be able to do. Although the Norwegians are undeniably audio purists – you only have to attend a presentation by brand ambassador Anders Ertzeid to realize that – they do build devices that are not only intended for the audiophile at home. Just like the other Hegel amplifiers, the H390 therefore comes with a variety of streaming options built-in, both for the discerning listener and for people who just want to play some music without hassle. For example, you can use MQAfiles over USB or via DLNA, but also a nice playlist via Spotify. Apple users can also transmit all possible audio in lossless CD quality via Airplay.

What you won’t find for the H390 is its own Hegel app. The brand strongly believes that audio companies should focus more on the audio part, leaving app development to others. So you can control the amplifier with all kinds of apps and you can control it over IP, making integration with smart home systems easy. The path that Hegel took with the smarthome-friendly Röst is therefore continued.

For streaming your own files, the best option is to pick up a DLNA player app, such as Glider (iOS) or BubbleUPnP (Android). The advantage of the latter is that it not only streams its own music files from a NAS to the Hegel; thanks to a clever tweak, BubbleUPnP can also stream from Tidal or Qobuz. Hegel himself also recommends mConnect, a free app that also has its advantages.

Although the H390 often looks the same as the H360 in terms of streaming, there are still important novelties. That’s because the new Hegel amps have an improved streaming section that makes much more possible. The support for MQA is one element of that, in addition to the ability to perform updates online. Nice, but even better is that an update is planned to make the H390 Roon Ready. Lovers of the audiophile software can therefore easily stream music in the highest quality. It is a possibility that we also expect in this price segment. It is not yet known when the update will appear. That was true when this review was written in 2020 (it originally appeared in FWD76) and is still valid in 2021. The Norwegian company has had a lot of setbacks in software development due to corona, among other things. but says it is now close to releasing the Roon update. Until then, Roon enthusiasts can still stream via AirPlay (which is supported by Roon) or via the USB input.

New DAC

The H390 comes with a different DAC section than its predecessor, now based on the Asahi Kasei Microdevices (AKM) AK4490 chip. In principle, this amplifier contains the same DA-converter as the large H590, but with that über amplifier the AKM-DAC was placed internally in a separate compartment to really avoid all interference. That extra step is not so relevant for everyone, but if you really aim for the real high-end it can make a difference. With the H390, however, we do not experience the DAC hatch as inadequate. It sounds fine. We have to admit: we are also a fan of AKM’s ‘Velvet Sound’. However, the implementation of a DAC chip is also very decisive. Hegel follows a very purist philosophy in this.

Thanks to the AKM chip, the Hegel amplifier can handle most hi-res audio, both in terms of PCM audio and DSD streams. Those who love MQA will also find something to their liking. The H390 is one of the few amplifiers that can handle MQA streams on the S/PDIF input, not just through the USB Class B port. Perhaps not so crucial for the European hi-fi enthusiast, but in Japan a relatively large number of music CDs with MQA files are released and played on players that are connected via an optical cable.

A lot of attention is always paid to the digital part of Hegel amplifiers, but you can of course also connect analog sources. The Norwegians strongly believe that you should especially embrace that DAC of the H390, which is why they provide three optical inputs, a coaxial, a BNC connector and a USB class B port. If you still want to use the DA converter of your source device, there are two analog cinch pairs and a pair of XLR inputs to link a source in a balanced way. At the back you will also find separate cinch outputs, with a fixed and variable output level. More unusual is that digital BNC output. In short, you can neatly integrate the amplifier in a home theater setup and connect some sources – but for a turntable you will have to provide a separate phono stage.

Minimalism from Oslo

It is telling that until now we have mainly talked about the technical side of the H390 and said nothing about the appearance. Usually we try to deal with the design first, because often it is the eye that is seduced first, then the ear. The H390 is a bit different, just like the rest of the Hegel line-up. This is mainly because Hegel is basically an engineering company that primarily strives for technical excellence, but also because it pursues a kind of Norwegian minimalism in industrial design. The company prefers a sober, understated design language that doesn’t try to pack you in with many lights or large VU meters. There is a large OLED display, flanked on either side by two large buttons. And that’s it. Even the on/off button is hidden from view. Not at the back, as often, but at the bottom in front. Fortunately, the amplifier stands on solid, vibration-damping feet, so that you can easily put your hand under the device.

Despite our predilection for eccentric design genre Chord and Devialet, Hegel’s sleek design language appeals to us. Perhaps because the H390 simply looks better in a living room than most hi-fi devices. The design is cool but controlled, and made to fit into an interior without disturbing it. Yes, you have to look closely to see the differences between the H190, H390 and H350 (or even older Hegels), just like you have to be a bit of a connoisseur to tell the different BMW models apart. But as with the Bavarian car manufacturer, this does not mean that the Hegel amplifiers lack a luxurious appearance. The H390 boasts a very good build quality and boasts a black powder coating that is much more scratch-resistant than the gloss or polished surfaces that other brands are passionate about. With its 22 kg, the H390 is also really a heavy thing. You can also say the same about the characteristic Hegel remote control, which fits perfectly with the whole. No cheap plastic box here that was quickly reordered afterwards. The Hegel remote is a heavy, metal rod with fine buttons that respond very well. Just don’t drop it on your glass coffee table.

Infinite Control

In a sense, reviewing a Hegel amplifier is always very challenging. After all, the explicit goal of those mean-spirited Norwegians is to build an amplifier that really has little color (read: distorts). The H390 is therefore very strong in disappearing from the display story. That almost sounds like a minus, but it really is a plus for the critical listener. With the Hegel amplifier you listen to your source (material) and to your speakers. That is a good thing for the audiophile who made well-considered choices in those areas, because he gets to hear what he has chosen. It does mean that sometimes the match does not work quite well or comes across as emotionless, probably because the connected speakers just need some coloring. Sometimes it is even a bit confronting;

However, with good speakers, the marriage with the H390 is often successful, very honestly. In some countries (such as the Benelux) Hegel is distributed together with KEF, so you often hear that combination at shows and at dealers. It must be said: the two go well together, which we also noticed when we paired the H390 with the KEF R3 speakers that we have in the test room. On tracks like ‘Angel’ by Massive Attack or ‘coelacanth’ by deadmau5, the amp convinces with absolute control over the KEFs, ensuring Angel’s intense and tough bassline never derails. This is a real challenge for both speakers and amplifier because the basses dive so deep and keep coming mercilessly, while the vocals, guitar line and the snare drum provide a lot of complexity. It can get messy quickly but the H390’s tight timing keeps the R3s tight in line. Fair: for their price, the KEF speakers are spectacularly good from a technical point of view. Also on our Focal Sopra N°2s – a completely different sound – the talents of the H390 are immediately evident. The Sopra’s are not terribly difficult to control in themselves, but only really come loose in the low end with an amplifier that has the necessary reserves. Not really a problem with the H390, as the deep thumps representing the artillery on Max Richter’s ‘War Anthem’ thundered through the room. Hegel’s clear-as-water approach also gives us one of the most honest representations of the Focal sound we’ve ever heard, giving deep and intense depth and intensity to the beautiful cello and piano work on ‘Eyes Shut’ by Alice Sara Ott and Olafur Arnalds. to come into its own. The enormous control and good timing of the Hegel amplifier also ensures that there is no blurring, so that information related to positioning in space comes through. You can visualize the immense space in which Ott and Arnalds seem to be playing, while you can even perceive those very soft sounds of the piano (such as the movement of the hammers). It’s a beautiful shot that the Hegel H390 delivers uncompromisingly.

Hegel H390 Conclusion

While the H390 isn’t Hegel’s flagship model, that says more about the hulking muscle that the H590 is than about this lower-priced (but still premium-priced) amp. If the H590 were not there, no one would doubt to grant the H390 the status of top model. It is a very powerful and controlled amplifier that can effortlessly drive challenging loudspeakers in a way that is nothing short of high-end. In terms of streaming functions, you not only have a lot to choose from, but the platform is also in full development. The addition of Roon – hopefully soon – is the icing on the cake.