PMC-00EX Precision 10MHz Master Clock

The master clock is the life of digital Audio.
All digital audio devices operate using the clock as a standard when they convert digital signal to audio signal, so the quality of the clock greatly affects the quality of the sound. It is the very pulse of digital audio.
Absolute precision is not the performance digital audio demands of the master clock.

The highest precision tuning meter (Strobe Scope)used by musical instrument makers has an accuracy on the order of 1/10 cent. One cent is 1/100 of a half tone (the musical interval between neighboring white and black keys on a piano). If you calculate the frequency, it is a precision of dozens of ppm. That level of precision can be easily obtained by any standard clock generator. The high fidelity generators used in normal high grade audio have 10 times that level of precision, and there is no significant benefit in demanding any more precision than that.

The clock performance needed by digital audio is phase noise (the frequency components outside of the generating frequency that shouldn’t be present, in other words, impurities), which affects jitter. The clock, which governs all operations of digital audio, should not be able to correctly restore audio, if it is contaminated by noise. Usually clock signals are supplied through the PLL circuits to the D/A converter. The PLL works as filter, so any noise with a frequency that is significantly different from the generating frequency of the clock generator can be removed. In other words, the noise from frequencies other than the generating frequency is determined by the performance of the circuits behind it. However, noise with a frequency that is very close to the generating frequency (neighborhood phase noise) cannot be removed by the filter, so when it is converted by the D/A, it becomes jitter. Just imagine, you can easily separate a pebble from a gain of sand with a sifter, but you cannot use a sifter to separate one grain of sand from another only slightly larger grain of sand. To suppress neighborhood phase noise, you have no choice but to use a clock generator with little neighborhood phase noise.

SFORZATO’s master clock generator provides a pure clock with miniscule phase noise, dramatically improving all digital audio devices with 10MHz clock input.

Dramatically low neighborhood phase noise
The PMC-00EX utilizes very low phase noise OCXO, which reaches neighborhood phase noise of -113dBc/Hz at 1Hz. Generally, rubidium-based generators only reach -70dBc/Hz. Even high-fidelity rubidium generators manufactured by American company used in leading audio makers only hit -100dBc/Hz at best. In short, the PMC-00EX offers nothing less than dramatic performance that leads the pack.

Robust chassis
Milled from ingots of aluminum, the robust chassis eliminates unwanted vibration and external noise to the utmost. Although in a single case, the power supply and OCXO unit are housed in a completely separate internal enclosure with a thickness exceeding 30mm.

Generous power supply
In order to make full use of the OCXO generator, we built a discrete high capacity analog power supply that uses a high-capacity 250VA toroidal transformer, 330000uF capacitors and high-speed, low noise SiC Schottky diode.

Internal wire management
We collaborated with Acoustic Revive to use their PC-Triple C elliptical wiring. The 10MHz output uses brass-tube-shielded, non-bendable rigid cables.

Specification
Output: 10MHz sinewave
Output terminal: BNC 50Ωx 1
Output level: 11 dBm
Size / Weight: 390 (W) x 256 (D) x 105 (H) / 17kg