DRA KIT (Digital→Analog Converter)

This project is the result of long-held dreams woven together.

One of these dreams is the KIT concept, which aims to make this level of quality accessible to those who want to finish, modify, or integrate it into an existing design according to their own vision. Another idea was to use older multi-bit chips, many of which are now available only at astronomical prices. Our choice fell on one outstanding example, the PCM56 manufactured by Burr-Brown. While some consider its limitation to 16-bit a disadvantage, its sampling rate extends up to 192kHz, performing above its specifications in practice. However, when you listen to this 16-bit quality, there’s no sense of anything missing. What stands out immediately is the incredibly deep, tangible, and plastic soundstage, with much richer harmonic overtones and spectral details in the instruments compared to newer technologies. Its dynamics are stunning.

The output signal from these converter chips is extremely low, so it is crucial to supply them with noise-free power. As is customary with Human Audio, we use batteries for this purpose, which is unique in the world of kits.

The basic KIT consists of an assembled, oscilloscope-tested working circuit without connectors and batteries. Of course, these components, as well as an aluminum case with plexiglass covers, can also be ordered. If desired, a fully assembled version is available. Depending on the factory-selected converter (PCM56P-J or PCM56P-K), voltage amplifier chips, and other components, the KIT is available at two quality and price levels (Standard and Plus).

It features two S/PDIF inputs with either RCA or BNC connectors and accepts signals with sampling rates up to 192kHz, though it does not support 176.4kHz. For those who enjoy computer-based music playback and experiment with various USB-I2S modules, we’ve provided an option to connect an external I2S signal via a pin header inside the converter.

This is followed by a logic circuit that solves the old problem of mono multi-bit chips: it distributes the data between the two channels with precise timing, without phase shift. Common solutions only handle this in a less accurate way. Additionally, there is no digital filtering or oversampling involved.

The current-to-voltage conversion is done passively, using a resistor and voltage amplification stage, output voltage is 2V.

Reviews:

TNT-Audio (English)
TNT-Audio (Italian)
Audiolife (Hungarian)

DISCONTINUED PRODUCT