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Nubert nuControl 2 and Nubert nuPower D Review

It is only a small, but all the finer product range that the German company Nubert electronic GmbH has to offer in the field of amplifier electronics. The focus is primarily on the Nubert nuControl 2 preamplifier, which is intended to present itself as an extremely flexible solution, whereby the company speaks of a preamplifier and sound manager. We asked this pre-amplifier for a test and immediately chose the Nubert nuPower D as the matching power amplifier.

Schwäbisch Gmünd has gradually developed into an extremely important location for hi-fi in Germany, not least due to the company Nubert electronic GmbH, founded by Günther Nubert as early as 1975. For years and days Nubert electronic GmbH has been developing and manufacturing loudspeaker systems, whereby the Swabians can clearly claim to do things differently from many in the industry. However, this by no means means means that Nubert electronic GmbH primarily acts as a direct mail-order company, but actually the approach in the development of their solutions and the ambition to always be able to offer a bit more than comparable solutions on the market.

Thus, the company has always pursued its own philosophy, and it fits in well with the fact that it has been focusing on active loudspeaker systems for a long time, not only for the professional and semi-professional sector, but also for the classic hi-fi segment. Nowadays this may not be a real speciality anymore, as more and more classic loudspeaker manufacturers in the HiFi segment recognized the potential of such solutions and also focus on active speaker systems. At Nubert electronic GmbH, active loudspeaker systems in various forms were already part of the product range when they were smiled at by many an audiophile in the hi-fi scene…

From active loudspeakers to electronics – a consistent step

However, due to the many years of experience in the development and production of active loudspeaker systems, it is only too obvious that this expertise should also be used for pure electronic solutions, i.e. the product range should be extended accordingly. It was the High End 2015 in Munich, Germany, when Nubert electronic GmbH for the first time launched a traditional combination of preamplifier and power amplifier in the form of the Nubert nuControl and the corresponding Nubert nuPower D.

Apart from the fact that the Nubert nuControl was an impeccable preamplifier which, together with the Nubert nuPower D Class D power amplifier, had a truly potent gaming partner at its side, the Swabian company’s corporate philosophy, as already mentioned, ensured that their electronics were able to celebrate great success right from the start, namely this principle of offering that little bit more than one is used to with comparable solutions. The Nubert nuControl is not just a preamplifier with analogue and digital interfaces, but rather a combination of preamplifier and DSP-based room acoustic processor. Nubert electronic GmbH wanted to provide its customers with a tool that would offer accurate adjustment to the respective room conditions and the loudspeaker systems used, in a simple but effective way.

As a further step in the expansion of the electronics division, Nubert electronic GmbH presented a further power amplifier in 2016 in the run-up to the High End 2016, namely the Nubert nuPower A, and thus a true power bolide, now designed in Class AB.

In 2018, Nubert electronic GmbH considered the time was ripe to devote itself once again to preamplification and presented the latest generation with the Nubert nuControl 2, with three areas of improvement compared to the first, namely signal processing, sound quality and ease of use.

Of course we have followed the development at Nubert electronic GmbH in the field of electronics editorially and always reported in detail, but we have so far failed to subject it to extensive testing. A real faux pas, as it turns out, because the Swabians – let this be said in advance – show here too that they know how to do things a little differently and deliver flawless solutions.

Nubert nuControl 2 – The interface

Of course, a preamplifier has a task to master first and foremost, namely to act as the central interface of a hi-fi chain. This is not so easy these days, because the demands that customers place on such solutions are very different. One hi-fi enthusiast is a proven analogue fan, while another prefers to use digital sources. Some prefer puristic solutions, assigning individual tasks to proven specialists, while others are also looking for highly integrated systems that combine a wide range of tasks in one solution.

So you can see that it is by no means easy for a manufacturer to reconcile all these different requirements.

With the Nubert nuControl 2, Nubert electronic GmbH once again takes a very pragmatic approach and thus offers a solid basis for a wide variety of strategies.

The Nubert nuControl 2 is equipped with both analogue and digital interfaces, but does without too much “specialisation” such as an integrated phono preamplifier, and all streaming options are left to external solutions. This is a very wise decision, as it allows everyone to build up the optimum chain for themselves.

Connection wanted…

A glance at the connection panel on the back of the Nubert nuControl 2 shows that you can hardly be embarrassed by not being able to connect any source. For example, three pairs of classic RCA sockets are available as analogue inputs, flanked by a pair of XLR sockets as a balanced alternative. It is astonishing that the same number of analog outputs are available for these inputs, also three pairs of RCA sockets and an XLR pair. In addition to a line out with variable level (RCA and XLR), there is also a pair of RCA sockets as a record out with fixed level and two connections for optional subwoofers. Nubert electronic GmbH knows its customers very well and therefore knows that many a bass fetishist is among them and appreciates the services of one or even two subwoofers.

For digital sources everything you could wish for is also available. Two coaxial as well as two optical S/PDIF interfaces serve as input, and if desired, one optical and one coaxial S/PDIF interface can be used as output to forward the signals to external components. These are also regulated outputs, which also benefit from DSP-based signal processing, but more on this later.

If you are using a PC or Mac as a flexible media centre, the Nubert nuControl 2 naturally has a USB port to connect it to the preamplifier so that it can be used directly as an exquisite audio interface.

It is interesting to note that Nubert electronic GmbH provides a trigger connection for controlling further components, but here it is not in the form of a 3.5 mm jack socket as is usually the case, but rather a mini XLR socket, which of course provides the typical 12 V for switching operations. The advantage of this is that it is a much more robust design, and since the power amplifiers from Nubert electronic GmbH also have a mini-XLR socket as trigger input, and since a corresponding adapter is included in the scope of delivery for components with a conventional connection, this is no reason for complaint, quite the contrary.

First contact…

The front of the Nubert nuControl 2 appears very tidy, but nothing else would be expected from Nubert electronic GmbH. After all, as described at the beginning, they have years of experience in the field of active loudspeaker systems, where a very simple operating concept is particularly important. In comparison, the developers of the Nubert nuControl 2 have been able to work very generously, so that the preamplifier is not only equipped with a clearly readable OLED display, a five-way control pad and two additional buttons as well as a rotary encoder to control the volume, and of course a standby button. For the sake of completeness, it should be mentioned here that a “real” power switch can of course be found on the rear panel.

Equipped for Hi-res Audio

With regard to the first generation of the preamplifier, it must be said that it was not quite up to date in the processing of digital data, a shortcoming that Nubert electronic GmbH has of course remedied in the second generation and thus in the Nubert nuControl 2.

The Nubert nuControl 2 is thus ideally equipped for processing hi-res audio through the use of DACs of the type Texas Instruments PCM1974, and can process audio data at up to 24 bits and 192 kHz on all digital interfaces, whereby, it should not be forgotten at this point, the UBS port is of course an interface with asynchronous data transfer.

DSP-based signal processing

What makes the Nubert nuControl 2 really special is the DSP-based signal processing. Here too, Nubert electronic GmbH benefits directly from all the experience gained in the development of active loudspeaker systems and can therefore implement functions in the preamplifier that are hard to find elsewhere in this class.

The manufacturer from Schwäbisch Gmünd, Germany, refers to this as a powerful digital signal processor, or even a sound manager, although it is interesting to note that some of the features of the Nubert nuControl 2 have been considered absolute no-go in audiophile circles for many years, but were state-of-the-art in the heyday of hi-fi in the 1970s and 1980s.

We are talking about very diverse sound control possibilities, and in a wide variety of ways. It was the declared aim of the developers to provide the user with simple but very effective tools to adjust the reproduction character of the preamp to the room conditions, his individual equipment and loudspeakers, but of course also to his personal listening experience.

To stay with the previously mentioned review of days long gone, who does not remember the sophisticated equalizers that were available from leading manufacturers for their hi-fi chains? Then all this disappeared, and many an audiophile turned up his nose in indignation at the simple bass or treble controls on amplifiers…

Well, the Nubert nuControl 2 takes up exactly this again, but in the most modern form.

First of all there is a seven-band parametric equalizer for the frequency range between 20 Hz and 20 kHz, which – and here the company from Schwäbisch Gmünd makes no empty promise – actually offers an extremely difficult way of intervening precisely and absolutely accurately in the frequency response of a loudspeaker system and thus effectively compensating for certain problems of the room acoustics or the loudspeaker itself.

And as if this were not enough, there is also a very sensitive loudness function, as it is level-dependent, as well as bass and mid/high tone control, which allow for further optimisation. Once again, the developers rely on the principle of a sound balance, which has been proven by Nubert electronic GmbH for years, so that the associated adjustments always have a harmonious effect on the entire frequency range, thus guaranteeing an even increase or decrease.

Even though it takes a little time to optimize each of the seven bands with all the available parameters, to make any further adjustments with the other intervention possibilities and to save all this as a preset, in our experience the intensive occupation with this really pays off. It’s impressive how subtly you can intervene here to solve some of the problems.

Proud owners of loudspeaker systems from Nubert electronic GmbH enjoy a certain initial advantage here, by the way, because for the most diverse loudspeaker systems of the Swabians, appropriate adjustments are already available ex works, whereby the manufacturer speaks of a kind of universal ATM. ATM, those are the Active Tuning Modules, which the company has been offering as optional accessories for almost all loudspeaker systems of its own program for years.

For those who prefer low frequencies…

One might think that this is quite a fine tuning of the signal processing for individual adaptation to one’s own circumstances, but Nubert nuControl 2 has a few more subtleties to offer. Especially for the aforementioned friends of solid bass and users of optional subwoofers. Not only can they connect two subwoofers at the same time, the Nubert nuControl 2 also offers the possibility to intervene in a very difficult way. Not only can the level and crossover frequency, including the slope of the crossover for the subwoofers, but also the signal delay between the satellites, i.e. the front speakers, and the optional subwoofers can be set to adapt the reproduction optimally to the room.

By the way, the Nubert nuControl 2 preamplifier is extremely compact, measuring the usual 43 cm in width, 38 cm in depth including controls, and is no more than 9 cm high. This brings it to 6.9 kg.

As if the technical features described so far did not already sufficiently underline the high standards of the developers around the Nubert nuControl 2, we explicitly want to emphasize the impeccable workmanship. The solid metal case has a simple, yet timelessly elegant design language, and the customer has the choice between a black or silver version. In both cases, the surface of the stainless steel case is brushed and the aluminium front is blasted with glass beads, with a matt lacquer being used in the black version.

The remote control included in the scope of delivery also leaves a pleasant, high-quality feel, apart from the fact that in principle all the essential parameters of the preamplifier are directly accessible, thus ensuring convenient operation.

Nubert nuPower D – The powerhouse…

Naturally, there is not nearly as much to tell about our second current test candidate as there is about the preamplifier. After all, the associated power amplifier, the Nubert nuPower D, is a system that serves only one purpose, namely to deliver as much power as possible, but of course with the appropriate “control”.

You get the power…

And one thing can be said with certainty, the Nubert nuPower D really does deliver more than enough power. The fact that the manufacturer is talking about a powerful stereo power amplifier can almost be declared a “shameless” understatement. Loudspeaker systems with an impedance of 4 Ohms have a full 920 Watts available, twice, mind you, and designated as continuous output power. This is made possible by a very generously dimensioned switch-mode power supply that can provide up to 4,000 watts, so that the music power even reaches up to 1,290 watts twice. If the loudspeaker systems have an impedance of 8 ohms, this is still twice 780 watts of continuous output power or twice 920 watts of music power.

It’s “little”…

Class D technology ensures that such a performance monster can be built with such compact dimensions. The Nubert nuPower D measures no more than 43 cm in width, 39.5 cm including connections in depth, and 9 cm in height. The weight is indicated with 9 kg. Remember, these are in principle exactly the same dimensions as those of the preamplifier described above. Even visually, the two solutions Nubert nuControl 2 and Nubert nuPower D make a perfect team.

It is noticeable that the Nubert nuPower D has only two control elements on the front, whereby the standby button with status LED is of course nothing special, but the rotary encoder, which is designated as the “Selector”, is. This allows to select the different operating modes of the power amplifier, “A”, “B” and “A+B”.

What this is all about can be seen immediately by looking at the rear panel, where there is not only one pair of speaker connectors for the left and right channel, but a total of four. These are of extremely solid construction and can accommodate banana jacks as well as bare cables with a cross-section of up to 6 mm2.

As far as the inputs are concerned, you can opt for either an unbalanced or balanced “path”, since in addition to the obligatory pair of RCA connectors, two XLR connectors are also available here.

Of course, a 12 V trigger input is also a must, so that the power amplifier is switched on at the same time as the preamplifier. As mentioned before, this is not a 3.5 mm jack socket, but rather a mini XLR.

By the way, it goes without saying that the Nubert nuPower D is equipped with a protection circuit against short circuit, overheating and direct current at the output.

There’s nothing more to say about the Nubert nuPower D, except that it is of course also impeccably finished and features a glass bead-blasted aluminium front and brushed metal housing.

From the practice

Normally, especially with amplifiers in general, and thus also with a classic pre- and power amplifier combination, you unpack the fine new parts, set them up at their destination, connect source devices, speakers and power, and get started.

Of course, this is basically no different with our test combination consisting of Nubert nuControl 2 and Nubert nuPower D, but before doing so, one should take note of the advice that the manufacturer himself mentions several times on his website, namely take a look at the manual. It is not that there is anything that could cause problems for new customers during installation, but rather that Nubert electronic GmbH actually took the trouble to explain in detail all the possible applications of the amplifiers. This might be helpful in finding some configurations that were not considered before, such as the combination with a possibly existing AV system.

And then of course there is everything that makes the Nubert nuControl 2 a special preamplifier, namely the DSP-based signal processing and its possibilities for room correction or optimal control of loudspeaker systems.

At this point we would like to advise you to make use of these possibilities, at least to experiment with them extensively. We are quite sure that there is a lot of potential for optimization. If necessary, Nubert nuControl 2 offers the option of bypassing the entire signal processing at the touch of a button by means of a direct function, which is not least practical for carrying out a before/after comparison at any time and checking that you are actually on the right track with the changes…

Even though it was offered to us by our friends at Nubert electronic GmbH, we deliberately decided against testing this pre- and power amplifier combination with loudspeaker systems of the same origin. We simply had nastier plans, namely to test this combination on our KEF Blade, just as the amplifier combination from Schwäbisch Gmünd had to prove itself on speakers from France, namely Triangle Cello Magellan. In other words, loudspeaker systems that in one case are significantly more expensive, in the second case many times more expensive than the entire combination from Germany, and loudspeakers that, at least in the case of the KEF Blade, are also very demanding when it comes to the “right” electronics.

As much as we love our KEF Blade, we know that it’s better to bring out the real heavy artillery to actually get it to play. And lo and behold, this was not really a problem for the combination from Nubert electronic GmbH. It seems as if the often quoted saying, according to which performance can’t be replaced by anything, is coming true…

Of course, the Nubert combination couldn’t take the KEF blade to the limits of its performance, so you have to realistically keep in mind the completely different price ranges, but the fact that the electronics performed so well and were really appealing in the end was a mark of great respect. Chapeau!

The combination of Nubert nuControl 2 and Nubert nuPower D mastered the challenges it was set with ease, one thing in particular stood out, namely that this combination once again consciously takes a neutral stance and reproduces exactly what is presented to it over a wide frequency range. This proved to be “dangerous” in the course of the test, especially in combination with the French speakers, because the first generation Triangle Chello Magellan tends to get a bit too intense in the high frequency range and is a bit annoying in the long run. But before this became too “british”, especially on some of the more “undercooled” tracks from the 1980s and 90s, the DSPs were used. As said before, there is always something to live out the play instinct and to get better results! With the Nubert nuControl 2 at hand, all this is just a few button clicks away.

By the way, Nubert electronic GmbH may now forgive us for this, but those who operate the combination consisting of Nubert nuControl 2 and Nubert nuPower D on appropriate floorstanding loudspeakers that have no proven weakness in the bass range are unlikely to be put at a loss to benefit from the extensive adjustment options for optional subwoofers. Because electronics that know how to set the four bass drivers of the KEF Blade vibrating in such a controlled way will hardly weaken at “smaller calibres”. However, this does of course open up the possibility of optimally operating even fine bookshelf speaker systems, because even fine solutions in this segment naturally profit immensely from a solid “underpinning” in the low frequency spectrum.

Perhaps a few words about the basic equipment especially of the preamplifier. As we have already mentioned, the developers at Nubert electronic GmbH obviously wanted to create a system that is as flexible as possible without too much specialization. So it doesn’t seem to us to be a “deficiency” that there is no integrated phono preamplifier, that an integrated headphone amplifier is not used and that streaming is left to external specialists.

The Nubert nuControl 2 is a solid basis for any HiFi system, sufficient analogue and digital inputs allow the use of a wide range of specialists, so that in total, it is likely that significantly better results can be achieved. In addition, especially the absence of integrated streaming ensures value stability over many years. Just remember what was considered “standard” in streaming three, four or five years ago and is now obsolete or outdated. An open solution such as the Nubert nuControl 2 will also serve as a solid basis in four, five… years, whatever you connect then.

This is of course also true if you don’t rely on a power amplifier as your gaming partner, as we did for this test, but rather directly on active loudspeaker systems. We don’t want to forget to point this out explicitly, either.

Getting to the Point

With the latest generation of its preamplifier Nubert nuControl 2, Nubert electronic GmbH can present an extremely exciting solution that is much more than a pure control center for a wide range of analog and digital sources. The special attraction here lies in the DSP-based signal processing, which proves to be a versatile “problem solver” as well as a proven tool for accurately adapting the sound character of the complete hi-fi chain to personal taste. Of course, this preamplifier can be perfectly used on its own for controlling active speaker systems. If, however, passive speakers are used, then the Nubert nuPower D should be taken into consideration, because not only is the Nubert nuControl 2 the ideal partner for the game, but it is also an extremely powerful powerhouse that, like the preamplifier, is well above its price range. This makes it particularly easy to make a straightforward recommendation!

HiFiBLOG Award Excellent

Even the Nubert nuControl 2, as a pure prepress system, knows how to convince completely. Interestingly enough, this is also due to the fact that Nubert electronic GmbH concentrates on the essentials, i.e. simply sufficient analogue and digital inputs, but leaves special tasks to external “specialists”. Instead, the company relies on versatile DSP-based signal processing, which allows for flexible interventions in the sound character of the entire chain and thus allows adjustments to the room, the loudspeakers, or even personal taste. It is already a perfect control centre for active loudspeakers, for example. If you are looking for a classic pre and power amplifier combination from a single source, the Nubert nuPower D is a solution where the description “powerful” is a smooth understatement…

Manufacturer:Nubert electronic GmbH
Distribution:Nubert electronic GmbH
Price:Nubert nuControl 2 € 1.940,-
Nubert nuPower D € 2.450,-
The Good– Focused on the essential
– sufficient analog and digital interfaces
– extensive DSP functions
– flexible integration of subwoofers
– Power amplifier with outstanding performance
– neutral vote
– timelessly elegant design
– excellent processing
– compact design in view of the performance data
The Bad– An app for the extensive DSP functions would be desirable
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Michael Holzinger

Michael Holzinger, founder and editor-in-chief of HiFi BLOG and, has been working for years as a journalist in the fields of IT, photography, telecommunications and consumer electronics.

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