WAVEDREAM REFERENCE

At the heart of the Wavedream Reference is our custom architecture, crafted for the highest level of precision and ultimate refinement in audio reproduction. Our DAC is built upon a highly optimized and efficient AMD/ZYNQ chip for master control/network renderer and 4 FPGAs, one for each phase of the discrete conversion system. The machine runs a Rockna custom tailored Linux system which takes care of everything except audio processing – which is executed by the dedicated hardware blocks.

To achieve an elegant internal layout, we designed a 10-layer central core board for the digital front-end processing and the network renderer. A completely new dedicated low noise supply board was developed, as well as new conversion boards placed in a symmetrical configuration, two for each channel. Compared to the classic Wavedream, the design was optimized by shortening the clock and data signal paths and by using higher quality board-to-board connectors. Therefore, signal integrity was significantly improved. Furthermore, the toroid transformers and the display are shielded internally using a copper cage. The analog stages following the D/A conversion modules are hidden on the back of the left and right boards.

The Rockna philosophy for an exceptional DAC is mastering the art of connecting mixed-signal technologies in such a way that the output preserves all the fine nuances of the original recording. Many think the secret is proper digital processing, but that is just one piece of the puzzle. When moving the audio information from digital to analog domain, the clock system plays a critical role in giving a sense of realism, analog sound and creating audio 3D imagery. Most D/A converters take the easy route by relying on the ASRC (acronym for asynchronous sample rate converter) built in the chips they use. While the ASRC may have a sound signature in itself, the quality of the ASRC implemented in DAC chips is affected by cost and silicon real-estate, thus being prone to sound quality degradation.

In the Wavedream Reference we developed one of the most advanced, ASRC-free digital PLL clock solutions which gives the DAC the ability to perform like an analogic source, with a natural sense pf pace and rhythm. Another key element is that digital signals physically travel as high-speed analog signals and they must be treated accordingly. Bits are bits on an abstract level but on pcb traces, connectors, cables they are a succession of high-speed rectangular analog signals which are not perfect: they have rise-time, fall time and they could be plagued by ringing, spikes, reflections, crosstalk, phase noise(jitter) etc. This is why Rockna has perfected radio-frequency techniques to mitigate these issues which have the potential to ruin the pursued analog sound.

DAC MODULES

For the D/A conversion stage we developed a evolved version of the mighty DAC modules used in the classic Wavedream DAC. The modules themselves are complex pieces of technology, sharing a discrete sign-magnitude hybrid ladder topology, driven by a complex algorithm which is embedded into their own FPGA. They can sustain sample rates up to a few MHz and the output of the DAC modules is un-buffered, allowing maximum transparency and natural sound reproduction.

WAVELIGHT PRE/DAC

RECLOCKING & D/A CONVERSION

A combination between memory buffers, digital phase-locked-loop (DPLL) and a custom input clock-decoupling scheme provides effective jitter cleaning before the conversion itself. Using the advanced Femtovox2 technique, the final result will lead to an „analog” sound without compromises.

A high precision R2R discrete ladder is performing the conversion from digital to analog domain, driven by the FPGA algorithms. The Wavelight dac is capable of operating in pure R2R mode or in a Hybrid mode ladder*. Future firmware will allow the switch at the touch of a button.

*currently in development

QUALITY

Each Wavelight is manually assembled in Rockna factory, individually tested and undergoes our strict quality control process. We believe that sound should be complemented by detail in fit and finish, sturdy construction, thorough circuit design and reliability.

This is why we are using selected components such as high precision resistors or audiophile-grade decoupling capacitors. The chassis is entirely built from massive aluminium with anodised finishing and a fine brushed texture.

WAVELIGHT SERVER

FUNCTIONS AND OUTPUTS

WLS resolves a few important aspects of a modern audio setup. It virtually eliminates the need for a computer holding your core server; will eliminate the need for a strong CPU to perform PCM to DSD transcoding; and eliminate the need for a storage server. All these features are included into a sleek and stylish package, visually matching the Wavelight DAC.

ALL-IN-ONE

AUDIOPHILE

MUSIC SERVER

STORAGE

Wavelight Server was designed to host your music. From a basic 2TB to a maximum of 16TB of internal storage, it can keep internally thousands of music albums in high-quality, uncompressed format. Additionally, WLS has 3 USB ports, where you can connect external storage, and/or a NAS (Network Attached Storage) can be defined as music source for WLS.

FULL DRIVE

MANAGEMENT

WAVEDREAM DAC

 SOFTWARE DEFINED ARCHITECTURE

We always thought that high-end audio should be everything about innovation. Playing around with off-the-shelf available chips is fun and certainly a good and economic way to produce good sound. But once you want to design a cutting-edge product, the off-the-shelf approach doesn’t apply. Naturally, a custom solution, freed from the limitation of the available chipsets, come into place, allowing us to design and build from the scratch an entire digital audio system.

All building blocks of the Wavedream DAC concernig digital processing are built entirely on a single piece of programmable silicon – a FPGA . With a FPGA, it’s internal hardware architecture could be described by a piece of software (actually, a very complex one). When upgrading the Wavedream with new firmware, you actually change it’s hardware. This system allows great flexibility, obsolescence protection and let us improve the sound of your dac by changing it’s internal architecture, or add new cool features, or improve the existing ones.

CUSTOM DIGITAL FILTERS

The Wavedream upsamples any material with a fixed rate of 16x. The dac modules will decode the digital stream with a rate of 768Khz, or 705.6Khz, respectively, according to input sample rate. We found this rate to be optimal for analog performance of the dac modules. Behind this simple multiplication factor (16x) lies a huge processing power. The digital filters are made with the combined effort of 58 DSP blocks, resulting into a impressive figure of 15 GMACS of processing power.

The developed filters are unique. We avoided standard Nyquist rate filters as not providing the expected performance for the dac. After lots of mathematical simulations and careful listening tests, we have created a custom Parks-McClellan upsampling filter. There are three variations avaialble on current firmware: linear, minimumand hybrid phase. They are highly optimized filters, offering stunning performance with a large number of taps (5k), and they are different in regard of impulse response. For the linear phase, the ringing energy (Gibb’s overshoot) is equally split before and after impulse. Minimum phase type shows all this energy after impulse, while our special hyrid phase filter has a combined response between linear and minimum, exhibing very low overshoot before the impulse.

THE POWER SUPPLY

Naturally we have dedicated sections for digital and analog areas. There are 3 separate transformers, and all power supplies are low noise linear – no switchmode power supplies are used whatsoever. There are a total of 20 linear regulators inside the dac. We dedicated our attention to the dac modules regulators – which are designed from the scratch for low impedance and ultra-low noise.

CONSTRUCTION DETAILS AND INTERNAL LAYOUT

The Wavedream benefits internally from a carefully studied, full symmetrical layout. Shortest signal paths and proper design of the clock tree were our main guidelines. All off-board connections are made with LVDS standard for lowest intereference, high speed and minimal jitter.

The transformer section is internally shielded to prevent internal EMI leakage. The chassis is entirely made of black anodized aluminium with a maximum fronplate thickness of 20 mm. Switches are black ruthenium finish.

WAVEDREAM NET

FPGA-BASED HIGH PERFORMANCE AUDIO

The NET is built around a powerful digital audio core, which streams all audio data into a large RAM buffer. The audio data is clocked out after a ultra-low phase noise masterclock, making the machine close to a ideal source. The powerful FPGA engine takes care in exclusive mode of the disc playback, which is totally separated by the server side. Also, the FPGA contain a large number of DSP units which can be very effective in real-time processing of audio streams, saving lots of processing power from the server’s side CPU.

SOFTWARE FEATURES

The WDNET software pack is a dynamic collection of audio services. They are controlled over a simple and straightforward web interface which can be accessed from the phone/tablet or a local computer. Currently following services are supported

• Roon Server – recommended control app: Roon remote
• MPD Server – recommended control app: MPD control, MPDroid
• Upnp/DLNA
• Airplay
• HQplayer NAA
• Disc ripping – FLAC, WAV, MP3 on local storage

Återförsäljare

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