Wavedream DAC

THE SOUND YOU EXPECTED,
AND BEYOND.

We are proud to present our current flagship in digital audio reproduction. We believe it has the right ingredients to produce a sound that will honour it’s name. In the good tradition established by it’s predecessor, the Wavedream continues to push the limits of performance, design and sound quality.

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.

Wavedream DAC
Wavedream DAC

FEMTOVOX CLOCK SYSTEM

The clock is the heart of a digital reproduction system. It’s accuracy and jitter levels are critical in regard of sound quality. Only a very good clock system can make the way to the analog sound on the output of your DAC. If the clock is flawed, digital harshness will occur and the analog feeling of the music will be severely altered. Apart from the performance of the clock itself, equally critical is the construction of the clock tree (the clock distribution architecture) inside the DAC. The jitter amount that really counts it’s not only the performance of the clock itself – but the clock which actually enters the dac and is used for conversion – let’s call it the conversion clock. The conversion clock that enters the dac section relies on the clock tree, which is usually not just routing, but in most cases conditioning, altering it’s quality. A poorly designed clock tree can degrade significantly the clock quality entering the d/a section, even if the source clock has great performance.

With these facts in mind, we designed for the Wavedream an advanced clock system called the femtovox. With femtovox in place, one is assured that only extremely small amounts of jitter are present at the dac conversion clock input. It’s unique architecture employs that conversion clock is directly synthesised at the dac input, without any conditioning, giving constant jitter performance at any sample rate. The conversion clock is controlled with 1 ppb precision, while exhibiting about 300 fS of jitter. The smallest jitter figure in the world? No. The smallest jitter figure where actually matters? Probably.

Wavedream DAC
Wavedream DAC
Wavedream DAC

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 countless mathematical simulations and careful listening tests, we have created a convolution filter, from a Parks-McClellan equiripple, combined with a raised-cosine type. There are three variations avaialble on current firmware: linear, minimum and hybrid phase. They are highly optimized filters, offering stunning performance with a decent amount of taps (2k), 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.

Wavedream DAC
Wavedream DAC
Wavedream DAC

R2R LADDER DAC

For the effective D/A conversion stage, the Wavedream uses a sign-magnitude, pure multibit R2R discrete ladder solution which can sustain a maximum sample rate of 3 MHz. This refined architecture grants one of the most natural sound reproduction, provided that very accurate conversion clock is supplied.

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.

 

 

 

 

 

EXTRA MENU FEATURES

On the dac menu can be found a series of useful features. Let’s take a short walkthrough.

  • The preamp feature - The Wavedream has a 256 steps volume control which allows direct connection of a power amplifier. The volume control has 0.5 dB steps for a fine resolution setting.
  • The phase select feature – the user can change the absolute phase of the output signal.
  • The filter select feature – discussed above. The filters can be switched off for NOS operation.
  • The clock setting – there are 2 modes of the digital PLL response, stream and local. Please reffer to the clock technical document under the technology section for more information.
  • Dither – to improve R2R ladder linearity, ultrasonic dither is applied on the last 4 bits from the digital 24-bit word.

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.

        

 

Prices:

Platinum SE $8,085 inc GST

Platinum Balanced $11,535 inc GST

Signature SE $16,335 inc GST

Signature Balanced $19,635 inc GST

 

>Contact us for purchase information or if you would like to experience any of our products in person.

 
ROCKNA WAVEDREAM