The Puccini range features the award-winning Puccini U-Clock which is a separate Grade 1 system clock to further reduce jitter and improve performance. Matched with the Puccini Player it improves on an already spectacular sound and takes it into an entirely new domain. With the clock added, images snap into sharper focus and the music displays a substantially greater sense of authority and power as well as offering noticeably higher resolution of detail.
Puccini U-Clock also features a USB-to-S/PDIF converter, which lets owners play high resolution audio from a computer through the legendary dCS Ring DAC™ inside the Puccini.
dCS equipment is designed to generate and accept industry-standard Word Clock on 75 ohm coaxial cable. dCS Clocks will drive other manufacturers’ equipment designed to accept standard Word Clock. Non-standard clock formats must be assumed to be proprietary to that manufacturer.
USB has numerous modes for synchronising the audio between a host computer and an audio device such as a DAC. ‘Adaptive’ is the most popular of these, and involves the audio device synchronising itself to the USB ‘frame’ provided by the computer. However, this tends to give poor jitter performance so Puccini U-Clock operates in asynchronous mode, where the audio device synchronises the audio by providing a feedback pipe to the computer. The computer is effectively locked to the audio device, which then benefits from a much more accurate clock for dramatically lower jitter. USB is isochronous, which means that the host (PC) and client (Puccini U-Clock) both know how much bandwidth is available at the outset, so the host can guarantee that bandwidth will be available all the time.
Music files may be stored on an external Hard Disc Drive (HDD) or Network Attached Storage (NAS) in a different room, networked to a small, silent Mac or PC connected by USB cable to the Puccini U-Clock. When the user selects the audio for playback, the computer streams music from the HDD or NAS device, then outputs the data via USB.
|Clock Frequencies||44.1kHz or 48kHz.|
|Colour||Silver or Black.|
|Dimensions (WxDxH)||400mm/15.8” x 410mm/16.2” x 58mm/2.3”. Allow extra depth for cable connectors.|
|Clock Accuracy||Better than +/-1ppm when shipped over an ambient temperature range of 10°C to 30°C (guaranteed for 12 months from shipping). Typically +/-0.1ppm when shipped and stabilised.|
|Word Clock I/O||4 independently buffered outputs on 75Ω BNC connectors, all carry the same clock frequency. With the USB interface active at 32, 48, 96 or 192kS/s, the Word Clock outputs are set to 48kHz. With the USB interface active at 44.1, 88.2 or 176.4kS/s, the Word Clock outputs are set to 44.1kHz. USB Auto Frequency mode can be disabled from the front panel.|
|Digital Inputs||USB 2.0 interface on type B connector accepts uncompressed audio data at 32, 44.1, 48, 88.2, 96, 176.4 & 192kS/s plus DOP.|
|Digital Outputs||Puccini U-Clock will present data received via the USB interface, unprocessed, in SPDIF format via 2 x RCA Phono connectors. DSD in DOP format will be passed through unchanged.|
|Operating Systems||Tested on Windows XP/Vista/7 and Mac OSX. Operates in ‘Audio Class’ mode. Class 1 mode (limited to 96kS/s) is available and does not require special drivers to be installed. Class 2 mode requires the dCS drivers (supplied) to be installed on Windows PCs. Not required for OSX 10.6.3 or later.|
|File Formats||Packetised PCM at 32, 44.1, 48, 88.2, 176.4 & 192kS/s.|
|Start Up Time||Typically 1 minute to rated accuracy.|
|Power Supply||Factory set for 100, 115, 220 or 230V AC, 49-62Hz.|
|Power Consumption||3 Watts typical/6 Watts maximum.|
HiFi Plus, Issue 73, March 2010
Review by Steve Dickinson
The Absolute Sound, Issue 200, February 2010
Review by Robert Harley
Software v2.0x. This applies to units with serial numbers starting with PUC.
Last updated 11 Feb 2016.