Reviews

Review: Rockna Wavelight PRE/DAC – D / A converter, Pre-stage

Review:  Tonally balanced DAC with a slightly warmer timbre- One thing is clear: The Rockna Wavelight PRE / DAC won't leave my listening room anytime soon.

Review: Rockna Wavelight PRE/DAC- With the increase in digital sources beyond classic CD drives such as music servers, home PCs, streaming bridges, flat screens, etc., D / A converters, which can optimally meet the various needs of incoming data streams not only technically but also in terms of sound, are very popular Course. Additional utility such as a preamplifier function for level control and the connection of analog sources is of course also welcome, as the equipment fleet can be reduced by “another box”, namely the preamp. The Rockna Wavelight PRE / DAC, which is discussed below, is such a device ( price: 4,990 euros).

The majority of D / A converters are constructed around highly integrated circuits which normally work according to the delta-sigma principle. Input and output stages and often the power supply unit are originally developed, but the actual D / A conversion takes place in the converter modules supplied by manufacturers such as ESS Technology, AKM or Texas Instruments. Depending on the talent of the engineers, this can produce very good results. In addition, there is a developer group that leaves the given paths, even avoids them. Many of them attribute a higher tonal potential to the D / A conversion using resistor networks – so-called ladder DACs -, as was common in the early days of digital music reproduction, and they insist on devising the necessary control algorithms themselves.

These particularly busy developers include Nicolae Jitariu, head of the digital specialist Rockna, who founded the company in Romania in 1999. Jitariu came into contact with the Canadian high-end forge MSB Technologies as a developer and subsequently had access to the high-precision resistor modules that the Canadians used in their much-vaunted R2R ladder DACs. Jitariu received exclusive permission to equip their own D / A converters, the Wavequest and its successor Wavedream, with modules from MSB. A circumstance that probably boosted the reputation of the DACs to some extent. Rockna has long been building its own resistance modules of the highest quality.

This pleasure is not cheap. A symmetrically structured Rockna Wavedream in the signature version costs 16,490 euros, and for the previous entry-level offer, the asymmetrical Rockna Wavedream Edition, 6,490 euros were called up. With the Wavelight PRE / DAC, Jitariu has now devised a new R2R ladder DAC, which is positioned below the price of the (expiring) Wavedream Edition. Matching the PRE / DAC, Rockna’s roon-based Wavelight server is also in the starting blocks.

Das Anschlussfeld des Rockna Wavelight PRE/DAC

As the addition “PRE / DAC” suggests, the Wavelight also allows analog signals to be accessed via a pair of cinch sockets . For listeners who only want to connect a turntable, tuner or tape recorder in addition to their digital sources, this is a welcome opportunity to think about the right to exist for an additional preliminary stage. Although the volume control is digitally controlled, this signal path is designed entirely analog. Later more.

The Rockna Wavelight receives digital signals via S / PDIF (Cinch), AES / EBU, Toslink or USB-B. There is also an I2S interface which, like the USB input, can process PCM signals with a resolution of 32 bits and 384 kHz and DSD up to 512. With the other interfaces, 24/192 (optical: 176 kHz) and DSD64 are still possible. This makes the Rockna as sociable as you would expect from a modern D / A converter in this price range. A nice, rarely encountered feature is the option to configure the I2S input differently in order to ensure cooperation with sources from non-brand manufacturers. Since there is no binding standardization for the HDMI / I2S interface so far, the connectivity was often not given. Incidentally, this is one of the features that the Wavelight was given with an update of the firmware.

In der Bildmitte: Die Steuerzentrale des Rockna Wavelight PRE/DAC, der Xilinx-7-FPGA-Logikbaustein

This is made possible by a Xilinx Spartan 7 FPGA logic module, which, in conjunction with the resistor network, represents the heart of the converter. In such a free programmable gate arrayNot only can essential functions and algorithms for controlling the R2R-DAC be removed, adjustments and optimizations can also be made at any time, or new, additional equipment details can be implemented. It is not entirely out of thin air when Rockna claims that this is blurring the lines between software and hardware. If necessary, the FPGA can be reprogrammed by downloading the appropriate firmware and sending it to the DAC in the same way as music files. For example via a computer used as a source or, as in my case, with the help of the Innuos Zenith SE. To do this, the corresponding update has to be imported into the Innuos’ music database via a USB stick, because the stick cannot be plugged in directly on the Rockna.

Die D/A-Wandlung erfolgt beim Rockna Wavelight PRE/DAC mit einer Widerstandsleiter

Before the digital data stream is re-clocked, which takes place with high-precision 300 femtoseconds, a complex structure of FIFO buffers and digital phase-locked loops remove jitter that could damage the sound , says Jitariu. The digital filters following the conversion are proprietary, as are the algorithms that convert a DSD stream into a PCM signal. The actual conversion takes place via a 25-bit resistance ladder, which is controlled by a program stored in the FPGA.

The output stages of the Rockna Wavelight PRE / DAC are discreet and the power supply houses two toroidal transformers that supply the digital and analog modules separately . The filter capacity of 100,000 µF available in the power supply unit has been dimensioned generously for a D / A converter. The symmetrical design of the analog signal path also fits well into the picture. In terms of sound, there is no noticeable difference between the XLR and cinch sockets, but the symmetrical outputs can safely be expected to have longer cable runs.

Der Rockna Wavelight PRE/DAC lässt sich mit drick Knöpfen auf der Front bedienen

The DAC is operated using three buttons on the front panel – or using its own app that connects to the device via Bluetooth when loaded onto a mobile phone or tablet. In addition to the input selection and level control, it can also be used to control the digital filters. It is not uncommon, however, that my Android devices cannot establish a connection to the Rockna. Following a tip from sales, I downloaded the app onto my wife’s iPhone on a trial basis and lo and behold, this problem does not occur with iOS.

 

Unfortunately, this does not change the fact that the volume control, which is often requested, especially in the preamp mode, always has to be time-consuming to be called up on the otherwise quite clearly designed remote app and larger level jumps take a little longer than usual. In addition, Surface steadfastly refuses to follow the rotations of the display. From the sales side it can be heard that appropriate improvements are already being made.

Rockna Wavelight PRE / DAC: hearing test & comparisons

The music servers Innuos Zenith SE and Innuos Zen Mk.3 as well as Electrocompaniets EMP2, a multiplayer that I use as a drive  – connected to a D / A converter via the coaxial S / PDIF interface – serve as the player for the Wavelight PRE / DAC . In the listening room, the DP-777 SE from Abbingdon Music Research usually does the converter job. I still have vivid memories of the sDP-1000 from the Korean manufacturer SOtM, which I recently parted with. Both of these are not mere sparring partners for our test subjects, but serious touchstones in the four to five thousand euro class.

 

 

Blick unter die Haube des Rockna Wavelight PRE/DAC

A question of the filter

Time to say a few words about the Wavelight’s digital filters. In contrast to the SOtM, whose upsampling can be selected in stages, only subtly influences the sound, or to the AMR, which, depending on the source, always has a really easy-to-hear filter, the Rockna makes fine changes that are definitely inviting for discussion. The Wavelight PRE / DAC offers four options: linear, minimum phase, a hybrid phase filter and NOS (non-oversampling). The latter means that the signal does not pass a digital filter.

Spontaneously, “linear” may seem worthwhile – but the digital filter of the same name isn’t really, it seems a touch too sterile in my ears and therefore not live enough. This is not the case with the minimum phase filter, which only has some post-ringing and no pre-ringing. With him, things are much more lively, a little warmer and more spacious. The hybrid-phase filter can be recognized by less pronounced post-oscillations. The ear registers a close relationship to the minimum phase filter, but at the same time perceives crisper impulses and more attacks. A really good filter. Still – the relaxed, unexcited laid-back pace of the minimum phase filter appeals to me no less.

Der Rockna Wavelight PRE/DAC im NOS-Modus

For those with a puristic disposition, filterless non-oversampling is the silver bullet. NOS is still not my favorite, the hybrid and minimal phases simply hit my hearing taste even more – NOS plays nicely detoxified, but at the same time a touch more sober and less thrilling. In the following hearing test, therefore, the minimum phase and hybrid filters are mainly used.

Tonal & more decisive

There will probably always be tonal flavor notes such as warmer, leaner, higher-pitched or stronger bass, regardless of the digital filter selected. However, the deviations from the ideal of a balanced frequency response are fairly manageable with current D / A converters. The Wavelight PRE / DAC is no exception.

Hopp (and Smile) , a project by K arl Seglem and Christoph Stiefel , may ostensibly appeal to younger listeners, but is at the same time a gem in terms of recording technology. On track 5, “Pirouette”, the keyboard instrument sounds very pure and unadulterated. But “Pirouette” is more than just a tonal litmus test, here the tones are put under enormous pressure. You can discover interesting details that tend to fall by the wayside with less sensitive equipment. The Rockna Wavelight allows the strings to vibrate great and the wood to resonate realistically. Its timbres are tempered a bit more sonorous than those of the SOtM DP-1000, which makes the instrument look even more real.

Apart from the slightly warmer timbre of Rockna, it is not the tonal differences that separate the wheat from the chaff. The Questyle CMA-600i, which is incredibly good for the money and whose converter section I used with great satisfaction, was able to convince with an impeccably neutral pace. The relevant differences to the DAC headphone preamplifier, which costs just € 1,300, are revealed in the resolution. Here the Wavelight leaves both the Questyle and the SOtM behind by a fairly large margin. What this ladder DAC can tease out of “Pirouette” in terms of micro-details has amazed me to some extent. Pay attention to the fading of the grand piano or to background noises such as the creaking of the piano chair,

Rockna Wavelight PRE/DAC - seitlich Perspektive

Dynamics!

The fact that the Romanian converter is dynamically not a child of sadness can be seen without much effort from the way in which he knows how to implement Christoph Stiefel’s attack. Powerful and confident, never clumsy, but finely differentiated according to the artist’s intention. Air upward? Well, the impact of the hammer heads on the steel strings could be even more emphatic, with more ping instead of pong, something like what I experience in a concert. But these are Petitessen – which are known to have to be paid for with hefty surcharges in high-end regions.

Quite a few converters get along well with individual impulses, but flatten out dynamically, become jittery and unfocused as soon as it is a matter of giving a large and wildly unleashed orchestra the necessary clout and authority – as for example in the final movement Allegro moderato from Mahler’s 6th Symphony(Gustav Mahler’s symphonies / Berliner Philharmoniker Recordings). Under their new chief conductor Kirill Petrenko, the Berliner Philharmoniker will deliver a fireworks display of sound, in which the two hammer blows, which are supposed to be based on Mahler’s premonitions of future strokes of fate (death of a daughter, Mahler’s own heart disease) can be heard. A third blow of the hammer, probably deleted from the score at the instigation of his wife Alma, is said to have indicated Mahler’s untimely death. Too scary, do you think? Then listen to the sentence with an entry-level DAC.

Rockna Wavelight PRE/DAC - von hinten, ohne Deckel

There is nothing to fear when D / A converters like the Rockna take on this task. Even in very densely woven instrumental passages, the Wavelight does not buckle. Its unusually firm bass allows it to accelerate dynamically, as it were, out of the basement, which gives it a real advantage over the AMR DP-777 SE, which has a less firm grip. At all, I can’t think of a DAC in the Rockna’s price range that could keep up in terms of control and stringency. Only “over-converters” of the cost-no-object league, such as those from DCS, Meitner and MSB, but also the wave streams from their own stable, can keep the Wavelight at a respectful distance with even greater dynamic composure. Even though it is a lot less than the price differences suggest,

With electronic music, such as Son Lux’s current album Tomorrows III , the gap could become even closer. The rockna reproduces the bass-potent impulses of the album with a dynamic vehemence that has so far been denied to me with other DACs in my own listening room. That he can descend a good bit deeper into the bass cellar than SOtM and Co. finally becomes evident with “Plans we make”, so much do the unexpectedly deep sub-bass waves collide with my unprepared diaphragm and provide a pleasant massage.

On stage

If you are not afraid of investing in a Rockna Wavelight, you do not have to worry about things like plasticity and holography of the image. At Making Music by percussionist Zakir Hussein, with quite a congenial support from John McLaughlin and Jan Garbarek, I would like to walk around among the virtuoso musicians and ideally pick up one of the small drums myself. A great ECM recording, which, although it was digitally recorded in the Rainbow Studios in Oslo in 1986, has hardly any patina.

Before you ask what happens to the room mapping, let me make it clear that the Wavelight itself of course does not “make” a room. It must already be available on the source side, then there is also it with the Rockna. It reproduces what is fed to it. It can be a little bar in which a bad-tempered sound engineer has put a mediocre string quartet or the expanse from the Marlboro advertisement (does anyone still know it?).

The prepress function

With the Rockna Wavelight, that’s not all. At least Nicolae Jitariu emphasizes that the analog input of the Wavelight is anything but a solution to the problem. The possibility of being able to dock an unbalanced analog source makes sense, in any case – if not particularly original. Both AMR and SOtM, and even the cheaper Questyle CMA-600i, also have this option. SOtMs sDP-1000 even has two analog cinch inputs and one XLR input.

Der Rockna Wavelight PRE/DAC ist auch in silberner Ausführung zu haben

Nicolae Jitariu had the obvious idea to use the high-precision resistors of the R2R ladder for level control, which do not have to convert in this operating mode and can therefore take over the job; of course he wrote the control program himself.

Rockna Wavelight PRE/DAC in Silber - ohne Deckel

To create the fairest possible conditions, I activate the analog outputs of the Electrocompaniet EMP-2 and play SACD and CD alternately via the preamplifier section of the Rockna and via my Silvercore preamps Linestage Two and Preamp 324.

Acting as a preamplifier, the Wavelight puts the wind quintet Profive (classical wind quintets, SACD) on a remarkably wide and deep stage and lets as many details pass as the two full-time preamps. Tonally, it is set a little more cautiously at the frequency response ends than the silver cores. Discussions about differences in coarse and fine dynamics should more or less only be useful for an academic exchange of blows. I mean, even if the guys from Profive really blow their horns, the differences are only minor.

The fact is: none of my preamp-capable DACs has ever scratched this close to the sound of the two preamps. Nevertheless, owners of proven sounding preamplifiers do not have to grow gray hair, because they usually counter with a little more pressure and plasticity. In addition, Silvercore’s Linestage Two in particular pampers with the more saturated timbres and the more spacious stage image.

Conclusion – Rockna Wavelight PRE/DAC

Rocknas Wavelight PRE / DAC belongs to the guild of Ladder DACs. Nothing is off-the-peg, but has been developed and designed from the ground up – the fact that the manufacturer’s experience with its big brother Wavedream has flowed into it is, of course, anything but a disadvantage.

The externals are quickly ticked off. The stable housing offers the electronics safe protection, is neatly processed and cuts a good figure in terms of design. Looking at the many proprietary developments relating to the Wavelight PRE / DAC, one suspects that the budget has mainly been invested elsewhere.

If it’s only about the sound, the Rockna Wavelight shows the taillights of pretty much everything that has done D / A conversion in my listening room so far. Powerful timbres, lifelike dynamics, fine resolution – the Rockna succeeds in fulfilling almost the entire canon of common assessment criteria with ease. He is anything but a soulless model boy, but a first-class music machine. Assuming really good, high-resolution recordings, even my analog set-up has a lot of trouble maintaining the usual distance. In short, this is a DAC with skills and talents that I would have previously suspected in significantly higher price regions. One thing is clear: The Rockna Wavelight PRE / DAC won’t leave my listening room anytime soon.

Profile Rockna Wavelight PRE / DAC

  • Tonally balanced DAC with a slightly warmer timbre, without thickening effects.
  • Stable, powerful bass with unusual depth. Always well controlled.
  • Pleasantly neutral in the middle. Not a “drama queen” and not as luxurious as with some tube DACs, but closer to reality.
  • The treble comes organically and perfectly integrated without sacrificing clarity.
  • Extremely plastic, almost holographic DAC. Sound bodies are reproduced with an unusual materiality.
  • The room mapping is based on the specifications of the recording. The DAC does not add anything, but can create very deep and spacious sound images if required.
  • Great fine resolution that has nothing nervous or even striking about it. Details are always presented as a matter of course, which can appear strikingly real.
  • The Wavelight is able to implement particularly (roughly) dynamic programs with emphasis and penetrating power, while it comes surprisingly close to expensive reference converters. Overview and control, even in the turmoil of the sound, are guaranteed. Fine dynamics are also easy for him to do.
  • Equipment and connectivity meet almost all requirements and wishes. The only thing missing is a physical remote control. Workmanship, design and housing quality are appropriate for the price range.

Facts:

  • Product: Rockna Wavelight PRE / DAC
  • Category: D / A converter (Ladder DAC)
  • Price: 4,990 euros
  • Dimensions & weight: 430 x 300 x 55 mm (WxDxH); 7.25 kg
  • Colors: black or silver
  • Inputs: digital: 1 x HDMI (I2S interface), 1 x S / PDIF coaxial (Cinch), 1 x AES / EBU (XLR), 1 x USB-B, 1 x Toslink; analog: 1 x line level (cinch)
  • Outputs: 1 x XLR / balanced, 1 x RCA / unbalanced
  • Data rates: maximum 24 bit / 384 kHz (PCM) and DSD512, no MQA
  • Other: volume control, mute, phase reversal, three filters: linear, minimal phase, hybrid phase plus NOS (filterless), proprietary app
  • Guarantee: 3 years