This ad is for 1 new Rockna Signature single ended (non balanced version) dac. Rockna Audio is relatively new to the North American market but well revered across Europe. The designer has designed and worked with MSB, Goldmund and PS Audio. Every Rockna dac and server is hand built in Romania. We have personally A/B tested 76 different digital front ends and our personal reference is the Rockna Signature dac and the matching Rockna Wavedream net server via i2S connections. The built in volume control is a custom 256 step with 0.5 adjustments. No need for an
expensive preamplifier. We have provided information from the Rockna website and we encourage you to read thru this information because this is truly a special dac and this is how you build a dac from the ground up.
Information from the Rockna website;
SOFTWARE DEFINED ARCHITECTURE
We have 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 economical way to produce good sound. But if 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, comes into place, allowing us to
design and build from the scratch an entire digital audio system. All building blocks of the Wavedream DAC concerning 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 its internal architecture, or add new cool features, or improve the existing ones.
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 its 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 synthesized 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.
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 available on current firmware: linear, minimum and
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 hybrid phase filter has a combined response between linear and minimum, exhibiting very low overshoot before the impulse.
For the effective D/A conversion stage we developed dedicated dac modules called RD-0 (used in Signature – 27 bit structure) and RD-1 (used in Edition – 26 bit structure).
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. Therefore the dac modules firmware is updatable both performance and feature-wise. Currently RD-0/1 can sustain a maximum sample rate of 6 MHz, which is the industry’s maximum sample rate specified for
a audio dac. The output of the dac modules is un-buffered, allowing maximum transparency and natural sound reproduction.
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 switch mode 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 interference, high speed and minimal jitter. The transformer section is internally shielded to prevent internal EMI leakage. The chassis is entirely made of black anodized aluminum with a maximum front plate thickness of 20 mm.
Switches are black ruthenium finish.
Exclusive stores that are now carrying Rockna.
27 W 24TH ST STE 506, NEW YORK, NY 10010-3277
11413 Runnel Ridge Rd, Manor TX 78653 "tel:512-373-5797"
Worldwide Wholesales Distributor
Canada/USA "tel:519-619-9924" [email protected]
Shipping in Canada and the USA is $100 via DHL Express.