With the adda191 reference, music transmission in the sense of ACOUSENCE is taken to the extreme. As with the adda191, the focus is on natural sound and artistically captivating, emotionally moving music reproduction. Music should be converted back and forth between the analogue and digital worlds as unadulterated as possible.
However, the DA converter in the adda191 reference is now built in “arfi-reference DAC” topology, which means that a total of eight DAC outputs generate the stereo signal in an ingenious way using premium transformers in the I/V stage. This provides an even more refined resolution of the smallest nuances while maintaining a very coherent reproduction of the music. An external controller for the internally realised volume control is also available as an option, making the DAC the ideal solution for high-end monitoring.
Compared to the adda191, the AD converter now has a whole series of functional enhancements. This gives the user a wide range of sonic possibilities; in principle a whole colour box for imaginative producers: With the “passive” button, the adda191 reference can be set to the classic mode of the adda191 and its predecessors, where only our special purely passive analogue input stage is used. Otherwise, however, the active amplifier stage is also looped in. The level of line signals can now be adjusted in eight 2dB steps (maximum additional amplification of 14dB). A completely new feature is the ability to process microphone signals (eight 6dB steps and 72dB max.). In addition, the transformation ratio of the input transformers can be switched. The resulting level difference of 6dB can be equalised by the active stage if necessary, meaning that there are three different ways of processing the same signal level for line levels and two for microphone signals. Each combination has its own discreet signature, which can be used creatively, even though it always follows the idea mentioned at the beginning.
Otherwise, the adda191 reference, like the adda191, is a converter system in 19″/1U format, technologically based on the familiar arfi-adc2pro and arfi-dac2pro converters. The proven technology is supplemented by further optimised “arfi-femto-reclocking”, which is now also extended by the option of generating the high-precision reference clock from an externally supplied word clock. External sources via AES or word clock provide a level of precision that could otherwise only be achieved by using the internal clock generators. This module also takes over the clock distribution to the converter boards, thus ensuring the shortest paths and highest precision.
On the analogue side, the signal paths are lean and straightforward – in the audiophile sense of the word – and implemented with the best components. The analogue signal routing and processing is fully balanced. The volume control, which can be used via an optional controller, is realised using switched fixed resistors, i.e. in the best possible way. This controller can also be used to remotely switch other important monitoring functions. Various connection formats can be selected for the two digital inputs and the digital output. AES/EBU to XLR is standard. However, AES/EBU to RJ45 and SPDIF to BNC/cinch are also possible. An optical fibre module for bidirectional connection rounds off the optional range. This allows the ADDA to be connected to a computer, but guarantees no interference from the sound-critical IT world on the sensitive analogue signals (using a Toslink interface; not included).
