TUC USB Module


Recently USB interface gains more and more popularity as a way of streaming sound from a computer. The latter is connected to an audio system via a separate DAC. The irrefutable advantage of such connection is asserted by the ever increasing number of DACs equipped with a USB input. Audio experts announce that this ‘computer+DAC’ link isn’t just a fluke of fashion but a truly important way to build up a high quality digital audio source.

TUC (True USB Conversion) USB Module developed by us provides not only for a transfer of data from computer to DAC but also for a feedback to control this transfer process. Thus the computer and the DAC work in coordination as a single unified device.  

TUC is realized on FPGA and uses a unique algorithm for generating I2S signal. To work with this module special drivers were designed. In our opinion this algorithm functions better than the majority of contemporary XMOS-based USB modules.

The heart of this device is a high-precision clock generator (femto clock) with minimal phase noise. This femto clock is located in close proximity of the converter. By the way, it’s manufactured in Russia and each specimen undergoes military acceptance procedure.

Another important feature of the TUC Module is signal buffering. Prior to conversion the signal is saved in a memory buffer. Its optimal volume was found by us as the result of numerous experiments.

All abovementioned measures combined guarantee the necessary results, i.e. jitter is practically impossible to measure for its level is lower than the sensitivity thresholdof even the most precise measuring device.

TUC USB ModuleWe can proudly state that TUC USB Module is among the best USBs currently manufactured.

It’s also necessary to note that the high quality level of this USB Module explains the absence of a standalone USB converter in our lineup.

In our opinion I2S digital signal from the module’s output must be fed straight to the converter bypassing any intermediate elements of the circuit.  

With a stand alone USB converter these superfluous elements are unavoidable. In this case conversion into S/PDIF or AES/EBU and back into I2S is compulsory so are the input/output sockets and a coaxial or optical cable. All these inevitably cause jitter to increase. Meanwhile the advantage of the absolute signal clarity provided by our TUC Module vanishes into thin air. So what’s the use of designing a stand alone DAC?

DreamDAC Common USB/SPDIF converter–DAC connection

That’s why we refused to manufacture such a device: its introduction into audio signal flow decreases the digital signal’s absolute quality defined by TUC Module and therefore would degrade the overall sound quality.