Reference USB, the flagship USB cable representing the pinnacle of musical performance.
The QED Reference USB cable is designed to transmit high definition 24bit/192kHz digital audio between USB audio components such as a computer or storage device and a high performance DAC. It utilises a carefully engineered geometry including an integral Ferrite jacket, electrically isolated power conductors and an impedance controlled data lane to reduce timing errors within the digital signal, for cleaner audio transmission.
Floating internal ferrite jacket
QED Reference USB features an integral Zn/Mn floating ferrite jacket. When measured using an eye pattern generator at the correct data rate for high bandwidth USB, the cable exhibits 50% less jitter than competitor cables without the ferrite jacket. There findings indicate that ultra low jitter in an isochronous data stream results in an audible improvement in sound quality. Certainly, in listening tests, the Reference cable with the ferrite jacket was preferred to samples without the jacket.
Electrically Isolated Power Conductors
Many audio enthusiasts feel that USB power cables carrying charging currents and PC power supply spikes near to the isochronous serial data stream can have an adverse affect on sound quality. One answer is to remove the power cables altogether but this deviates from the USB spec and can cause inconvenience especially if the DAC electronics require USB power. QED Reference data lanes are uniquely electrically isolated by using a double layer shield comprising a 100% aluminium mylar wrap and drain wire connected to ground.
Impedance Controlled Data Lane
QED Reference USB uses a tightly controlled 24 AWG 99.99% OFC twisted pair which is tightly bound by an aluminium mylar wrap with a drain wire pulled underneath. This arrangement is identical to that used in our high performance HDMI cables and is not usually found in a USB cable. Because the impedance of the data lane is kept strictly within defined limits, the jitter added to the data stream is kept to a minimum.
Five nines oxygen free copper conductors, LDPE dielectrics and legendary build quality combine to create audible sonic improvements. Our extensive listening tests comparing it against competitor products at much higher price points have astonished us! We urge you to compare it not only to your favourite cable but also alternative brands and models at any price!
Ferrite Insulation Technology
A special floating Zn/Mn Ferrite jacket is used within the Audio 40 cordage to absorb very high frequency noise components outside of the audible band that have an adverse effect on the micro-timing of the audio signal.
Ultra Low Jitter
Jitter is the undesired deviation from true periodicity of an assumed periodic signal in electronics and telecommunications, often in relation to a reference clock source. A cable displaying ultra low jitter has been measured at typically 30ps.
The Reference USB cable will connect from the following devices:
Laptop, PC/ MAC, Network Drive and USB device
to the following receivers:
DAC, Headphone amp and USB device.
QED Reference USB Type A to Type B Cable
99.999% Oxygen Free Copper (OFC) twisted pair of 7/0.2mm insulated with a low density Polyethylene (LDPE) high performance dielectric- for sonic purity and low return loss
Dual screened conductors using an aluminium mylar wrap and an 99.999% OFC shield braid for triple electromagnetic screening coverage
Unique inner Zn/Mn impregnated ferrite screen -for advanced signal protection and reduction of unwanted frequency noise components
Ultra Low Jitter design for reduced timing errors
24c Gold plated plugs
Lifetime UK Warranty