OPTO•USB Optical Isolation

OPTO•USB is a USB optical isolator that provides RF isolated transmission of high-resolution digital audio from a USB source to DAC. OPTO•USB uses all-dielectric multi-mode optical fiber for total galvanic isolation*. A 30 meter cable length allows convenient distancing of digital source & networking away from sensitive DAC and analog components.

Operation with Windows, macOS or Linux is plug-and-play. Supports USB 3.2, USB 3.1 Gen 1, USB 3.0 and is backward compatible with USB 2.0. Integrated connectors: transmitter USB 'A' male (5V power direct from source USB port); receiver USB 'A' female with an associated USB 'A' male (5V supplemental power for optical demodulation).

Use short USB cables or adapters for connection from OPTO•USB receiver USB 'A' female to DAC USB input (USB ‘B’, USB ‘micro B’ or USB-C). Be aware that some 3rd party USB-C/A adapters may provide support for USB-C Power Delivery. This is an unwanted feature as it introduces RF noise from logic circuits and switch mode DC/DC power conversion. Dan recommends the optional USB-C Filter** + USB-C/A Adapter & Cable to greatly reduce source RF noise injection and ensure no added RF noise from the adapters.

Use ultra low noise 5V power for the OPTO•USB receiver. Dan recommends using PURE•DC @ 5V for ultra-low noise and ultra-low ESR (Equivalent Series Resistance) power for OPTO•USB and DAC. Integrate with SRC•DX for the ultimate transparency of DBNC input to Chord Electronics DX DACs.

OPTO•USB is a core part of Dan's REFERENCE•M2 system.***

*Avoid USB-over-optical solutions that embed a copper wire in the cable. This will conduct RF and act as an antenna for radiated RF noise.

** USB-C Filter includes an enclosing case.

*** OPTO•USB includes user applied heat sinks (per my REFERENCE•M2 system and supplied media drawing) as the receiver may get warm after long periods of high resolution audio transmission.