The Reference High Resolution USB sits at the top of QED's digital cable range, above the Performance Graphite and Connect USB models. Updated in 2020 with a slimmer, more flexible profile and enhanced performance, it is designed specifically for connecting computers, laptops and network streamers to external DACs for high-resolution audio playback at up to 24-bit/192kHz and DSD.
Impedance-Controlled Data Lane
At its core, the Reference High Resolution USB uses a tightly controlled 24 AWG, 99.999% oxygen-free copper twisted pair with silver-plated conductors. The data lanes are insulated with low-permittivity foamed polyethylene dielectrics and bound with an aluminium/mylar wrap, maintaining the USB 2.0 characteristic impedance specification of 90Ω ±5% across the full cable length. This controlled geometry keeps signal rise time to 100ps at 3m, ensuring clean data transfer at the full 480Mb/s USB 2.0 data rate.
Clean Path Audio Technology
QED’s Clean Path Audio technology electrically isolates the data-carrying conductors from the power supply lines within the cable. A double-layer shield comprising 100% aluminium/mylar wrap and a dense shield braid surrounds the data pair, preventing power-line noise from contaminating the audio data stream. The 24k gold-plated USB A and USB B connectors provide stable, corrosion-free contact surfaces at each end.
Ferrite Insulation Technology
The cable incorporates QED’s proprietary Ferrite Insulation technology — an integral zinc/manganese floating ferrite jacket distributed evenly throughout the cable structure. This absorbs radio-frequency noise both from external sources and from the cable’s own internal reflections. QED’s eye-pattern analysis at USB 2.0 data rates measured 50% less jitter compared to equivalent cables without the ferrite treatment, reducing jitter-induced distortion during isochronous audio data transfer.
| Connection | USB Type-A to USB Type-B |
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| Conductor | 24 AWG, 99.999% OFC, silver-plated |
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| Dielectric | Foamed polyethylene |
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| Shielding | Triple-layer (aluminium/mylar wrap + braid + ferrite jacket) |
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| Outside Diameter | 7mm |
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| Characteristic Impedance | 90Ω ±5% |
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| Signal Pair Attenuation | < -0.11 dB/m @ 480MHz |
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| Propagation Delay | 26ns max |
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| Propagation Delay Skew | 68ps max |
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| Maximum Data Rate | 480Mb/s (USB 2.0) |
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| Worst-Case Jitter | < 76ps pk-pk (5m @ 480Mb/s) |
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| Connectors | 24k gold-plated |
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| Also Available As | 0.6m, 1m, 2m, 3m |
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