M2Tech Evo Clock

Owner's Manual

The Evo Clock is a highly stable word clock generator that can clock many devices from the Evo USB to S/PDIF converter to the PC or Mac, or to an outboard DAC. By clocking devices together, all on the exact same timing, you eliminate jitter distortion and attain levels of resolution and clarity only heretofore available to the  ultra high end of audio components.

It All Starts With the Evo
The way all of these work together starts with the Evo. You connect the USB output from your computer/server to the USB input of the Evo. 

From the Evo, you can run any of the outputs into your audio, assuming it has a digital input. If you want to do a better job of reproducing the analog audio, connet the I2s output from the Evo to the I2S input of the Evo DAC. You can then send the analog output from the DAC straight into your preamp or integrated amp.

Add a 75 ohm BNC cable from the Word Clock output ot the Evo Clock to the Word Clock input of the Evo and your computer, Evo, and DAC will all be running on the same clock with extremely low jitter distortion.

A Word on Jitter
Jitter is the main form of distortion in a digital system. Even asynchronous connections based on precision oscillators may fail to achieve the ultimate performance theoretically due to jitter distortion injected in the system. Jitter has various causes. One is the inherent phase noise in every oscillator. Different kinds of crystal oscillators allow for different phase noise, thus different jitter levels. The most basic crystal oscillator is sensitive to many phase noise sources: power supply, coupled EMI, internal instabilities of the quartz, random temperature changes. Precision crystal oscillators have an internal compensation for the power supply noise, while TCXO (temperature compensated crystal oscillators) have a reduced temperature sensitivity thanks to specific compensation circuits. OCXO (oven compensated crystal oscillators) theoretically allow for the lowest phase noise. 

In commercial circuits, an OCXO is a waste of money (they are very expensive), as the environmental EMI and the power supplies which are generally used inject far more noise then the theoretical device’s noise floor. A good TCXO, with very low phase noise, coupled to low noise supplies in a well-shielded metal chassis is the best choice for a cost-effective, high performance clock generator. The Evo CLOCK is designed keeping these guidelines in mind: very low phase noise custom made TCXO’s are used, along with special low noise regulators to achieve very high performance