Extenders

If you have to bridge a long distance between PC and USB DAC; you can use an USB extender.

Make sure USB high speed is supported if you plan to use this with a >96 kHz USB DAC.

Beside extending the range, optical looks a nice solution to shield your DAC from the electrical noise of the PC.
As optical doesn’t transfer power it must be a self-powered DAC including the USB receiver.

Monoprice 2 Port USB-A to USB-A Female 2.0 Extension Cable - Active, Repeater, Black, 32ft - $11.57

Added 2018

Corning USB 3.Optical™ Cables $109.99

10 m
5 Gb/s data rate
Compatible with USB 3.0 and USB 2.0 devices**
Ultra-slim, “zero-bend” radius cable
Extends USB device reach without additional power supply
Hot swappable
Built in overcurrent protection
Enabled by Corning® ClearCurve® VSDN® optical fiber
Class 1 Laser Product

Also available in 15 and 30 meters.

An intriguing product as it is affordable compared with other USB extenders and isolates the PC from the DAC both on the power lines and the signal lines. As it doesn’t deliver USB power, you need a self-powered DAC including the USB receiver.
If you need power you can add a USB hub or a PSU like the Aqvox to supply the DAC with power.

MEASUREMENTS: Corning USB 3 Optical Cable, Ground Loops, and Noise. Archimago's Musings

Added 4/2014

CYP PU-USBX USB 2.0 over Ethernet Extender £ 112

Control up to 4 four USB devices
Supports high-speed (480 Mbps), full-speed (12 Mbps) and low- speed(1.5 Mbps) transaction (speed in the LAN Mode might be limited by the bandwidth of the network)
Works up to 100m away (in the Extender Mode)
Connect with existing Ethernet cable or directly to a PC with RJ-45 cable
Compliant with USB 2.0 (Hi-speed) specification
Support Ethernet protocols TCP/IP
Support 10/100/1000 Mbps Ethernet speed
Supports Windows 7, Vista, & XP OS

Inputs	1x USB Mini B [1x USB Hub - Propriety Data] 1x RJ45 [1x USB Extending - Propriety Data]
Outputs	4x USB Type A [4x USB - Propriety Data]

Gefen USB 2.0 LR USD 499.00

Extends high-speed USB devices up to 100 m over Cat5 cable.

Adnaco USB 3.0 Over Fiber Optic Expansion System US$ 347.00

The Adnaco-R1USB30 is a remote standard-USB 3.0 host controller which can operate at distances up to 100 m and more (depending on transceivers and cable) from the location of your computer. Powered by Adnaco PCIe over-fiber-optic technology, the R1USB30 was designed to suit many applications with the USB host interface. The R1USB30 provides 2 USB Root Hub Ports compliant with the USB 3.0 specification. All USB ports can handle the following interfaces:
• Super-Speed (5.0 Gb/s)
• High-Speed (480 Mbps)
• Full-Speed (12 Mbps)
• Low-Speed (1.5 Mbps)
The R1USB30 is connected to a host computer, equipped with the Adnaco-H1A card and a fiber optic cable. SuperSpeed USB is backward compatible with USB 2.0 devices and capable of operating with USB 2.0 platforms. The R1USB30 works with all USB systems and peripherals and does not require any additional software.

Icron USB Ranger 2224 Multimode Fiber Extender $900

The USB Ranger® 2204 is a four port USB 2.0 high speed extension solution, enabling USB 2.0 connections at up to 480Mbps over multimode fiber optics.

Sewel Light-Link USB, USB 3.0 over Fiber $48 (30 ft)

The Light-Link is composed of two fiber cables and two copper cables. The copper cables are used for non-data information such as +5v power for USB devices. The fiber strands carry all the data information. The Light-Link USB features a micro USB-B port to provide Auxiliary power for devices that require a little more power than usual.

Added 2016

StarTech US$ 599.99

4 Port USB 2.0 over Gigabit LAN or Direct Cat5e / Cat6 Ethernet Extender System - up to 330 ft (100m)

Can be used in a LAN or connected directly.

Max Distance	100 m / 330 ft
Maximum Data Transfer Rate	1 Gbps (LAN) 480 Mbps (USB)