The rest of the power supply continues in the spirit of not compromising parts quality. Think silicon-carbide Schottky diodes, large-capacity low-ESR and Oscon capacitors, next-gen ultra-low-noise linear PSRR LT3045 regulators in a three-stage cascade. The power supply itself is a two-stage affair whose second stage filters the first. The board uses 70μm copper traces so twice the standard thickness. The internal layout was subjected to extensive research to optimize the operation of each part. The feet are die-cast aluminium cylinders which for a slight surcharge can upgrade to decoupling spikes. Over several months the internal type 3 OCXO module is subjected to long-term calibration before being installed. Each production specimen is accompanied by a highly detailed calibration cert as though professional lab gear. This denotes rather unusual seriousness for consumer-grade audio. The clock output voltage can switch between 1.6/3.0Vp-p to accommodate almost all audio devices to market. Switching affects all four ports together. The low voltage seems most versatile. The high one is reserved for rare occasions where standard voltage is insufficient. The white LED on the front panel's right indicates optimum operating temperature by increasing in brightness until it equals the blue power indicator's strength. Beyond the two-year warranty commonly offered by hifi manufacturers, Cybershaft assure us that their clock parameters of phase noise and short-term stability (Allan variance over a second) will remain stable. Their -121/-140dBc @ 1/10Hz spec can only be guaranteed with short-term stability of 0.0002ppb/s. International standards don't clearly define this Allan variance. Different calibration labs can imply large offsets. The values published here were generated with Cybershaft's own measuring kit.
To complete Kenji Hasegawa's offering, BNC cables play a significant role. He makes a fairly inexpensive 50Ω cable that's fully shielded, semi rigid and accompanied by a standing wave report. SWR is a measure of an electrical waveguide's or transmission line's source/load Ω match. Impedance mismatches cause standing waves. SWR defines the ratio of a partial standing wave's amplitude between antinode (maximum) and node (minimum) along the line. A perfect value would be 1/1. Later Kenji Hasegawa added a more premium BNC cable with pure silver conductors (5 x 0.28mm, 1 x 0.30mm) and double-shielded coaxial makeup with 40μm silver-plated mesh. The CF-BNC(R) connectors from Furutech's upper catalogue add rhodium plating and carbon fibre. These cables use silver solder and have a characteristic impedance of 75Ω but according to Cybershaft give very good results with their 50Ω ports.
Discovering the sonic potential of Cybershaft's best clock was gradual. It takes a few days just to reach thermal equilibrium. Then there was the question of which BNC cable to use. That became a significant variable in the overall result. From the onset the semi-rigid 50Ω Cybershaft bettered my own cable. Then the 75Ω silver went much further still. At the small price asked, there's no reason to hesitate. It's really a godsend. Having an extra input to clock-sync my network switch added its own share of improvements. Hence the OP21A-D is really full of potential which I'll try to outline for you. Let's start by adding it to my Esoteric SACD and network players. On Bruckner's 2nd Symphony performed by the Altomonte St Florian orchestra under Rémy Ballot [Gramola], the feeling of relief and airiness gained in precision over the internal clock of Esoteric's N-05 XD. The soundstage widened and the second movement seemed less monolithic so undoubtedly finer and more modulated.
On Vilde Frang's Paganini/Schubert album, the violin was more subtle, melodic phrasing more finely chiselled, timbre more luminous. The soundstage again was wider with the Cybershaft clock. The separation of violin and piano in the "Fantasy in C major Opus 159" was clearer, the sensation of concertante dialogue more evident. When testing the OP21A-D clock with my Esoteric K-03 transport, the performance delta against its internal clock increased. It was clearly a big added value for all my SACD on dynamics, bandwidth and resolution. On Joseph Tawadros' The Hour of Separation album, the notes of oud and bass viol seemed to linger longer and string plucks came off with much better alacrity. Moving on to more conventional Jazz with Italian singer Roberta Gambarini's You are there CD, the same observations held, in particular about better bandwidth and greater definition. Other improvements were easily perceptible such as the sibilance present on the singer's voice which disappeared with the external clock, giving a sense of greater naturalness.
