soulution 760 D/A converter

Design

In many areas the 760 D/A-Converter is based on the same proven technical solutions used in the 745 SACD-Player. It also embodies the same principles in its design: top grade digital inter­faces for optimal reception of the music data, a super-precise master clock generator to avoid jitter, intelligent digital signal processing with over­sampling and Zero Phase technology, analogue output stages of top end pre­amplifier quality and a husky power supply.

The 760 D/A-Converter is packed with cutting-edge tech­nology with one objective – the love of music. The parallels include a consistent dual mono design in the output stages and separate power supplies for digital elec­tronics and the analogue stages. The 760 D/A-Converter adds a digital volume control that allows direct connec­tion to a power amplifier.

Oversampling

A powerful SHARC DSP performs the 8 x over­sampling to 24 bit/352.8 kHz or 24 bit/384kHz, depending on the digital input signa,l with the utmost precision. We believe precision of inter­polation is more impor­tant than high clock rates. Our players and D/A converters use an algorithm from the highly regarded Anagram Technologies followed by Burr Brown D/A converters in a digital symmetric configuration. As we consider the PCM conversion technology as superior, the DSD signals get converted before its final D/A conversion.

zeroφtech

The 760 D/A-Converter is equipped with soulution’s innovative Zero-Phase-Technology. Smallest timing errors provoked by the analog low pass filter of the D/A converter get eliminated. Every D/A converter requires an analog low pass filter in its output in order to suppress high frequency noise and aliasing signals. The 760’s 3^rd order bessel filter, with a cut-off frequency of 120 kHz, does show a phase shift of up to 15° in the audio band. Due to the Zero-Phase-Technology the phase error of the analog music signal remains below 1°, 20 Hz – 100 kHz! The Zero-Phase-Technology brings you even closer to the beauty of the source material! The music gets even more realistic and 3-dimensional with a lot of “air” around instruments and voices. As close to the source as possible! No detail gets lost.

Clock

Utmost precision of the clock signal is a must have for a top class D/A-Conversion. Lowest phase-noise behaviour is by far more important than long term frequency stability. Together with experts for highend oscillators we did develop a TCXO which is optimized for this application. It does not run on its first harmonic but on its 3^rd overtone. The clock modules work at frequencies around 100MHz, this re-quires extremely fast amplifier stages within the oscillator loop but allows achieving best results regarding phase-noise. Even the best OCXOs or rubidium based oscillators are not able to outperform these specifications. The 760 DAC does have a spate oscillator module for signals based on 44.1 kHz and signals based on 48 kHz. With the synchronisation to an external clock signal the performance of these oscillator modules would be deteriorated. Therefore the 760 does not provide a clock-input. However, external components can be synchronised to the 760 D/A-converters high quality clock signal through its clock-output.

D/A conversion

Burr-Brown devices perform D/A conversion only. Their internal upsampling and filter stages are not used. The output currents are converted to voltage and then filtered. With an internal bandwidth of 80 MHz, this current/voltage conversion stage allows best signal-to-noise performance and maximum dynamics in the analogue domain.

Output stage

The wideband output stage of the 760 D/A-Converter, which is based on an optimised circuitry with special power transistors which are further linearized by an analogue computing network, has a bandwidth of 40 MHz (- 3 dB). With such speed of response all musical details are reproduced true to life creating a three-dimensional, spatial sound to bring real listening pleasure.

Power supply

Key to any good sounding audio source component is a stable, noise-free power supply – especially for the audio stages. The 760 is equipped with two dedicated power supplies: one for the audio stages and one for the digital circuits. For powering the audio stages an innovative, amplifier-like circuit design is used, providing an extremely stable supply voltage. With more than 500,000 µFarad of storage capacitance it provides almost unlimited impulse current for the analog circuits. Bus bars supply this power throughout the 760 D/A converter without any losses. A unique concept in the audio world!

Operation

The 760 D/A converter is operated from front-panel buttons and a rotary control. Further functions can be used to optimise and match an entire audio system around different components.