CAD USB Filter

Computer Audio Design · Built-in Filtering Technology · Reduces USB High-Frequency Noise

The CAD USB Filter is an in-line USB filter from Computer Audio Design (CAD), specifically designed to reduce high-frequency noise generated by digital audio sources. Utilizing the same patented filtering technology found in the award-winning USB II-R cable, it plugs directly into the USB-B input of your DAC or streamer and works with any brand of USB cable, effectively blocking noise from entering the analog stage and enhancing sound clarity, dynamics, and rhythm.

Suitable for all high-end digital audio systems using USB connections.

Basic Product Information

• Type: In-line USB Filter
• Brand: Computer Audio Design (CAD)
• Connector Type: USB-B Male + USB-B Female (B-end Filter)
• Applicable Devices: DACs, streamers, music servers, and other equipment with USB-B inputs
• Compatibility: Can be used with any brand of USB cable
• Positioning: High-frequency noise suppression accessory for digital systems

Core Technology and Material Application

• Patented USB Filtering Technology: Developed in-house by CAD founder Scott Berry, using the same filter circuit as the USB II-R cable
• Comprehensive Filtering of All Four USB Lines: Simultaneously processes high-frequency noise on Data+, Data-, Ground, and +5V lines
• Designed for Proximity to DAC: Plugs directly into the device's USB-B input to maximize blockage of noise picked up by cables and interference from the source
• Passive Design: Does not alter data flow, re-clock, or regenerate; focuses solely on noise reduction
• Broadband Noise Suppression: Absorbs and attenu attenuates high-frequency noise (approximately 1MHz to GHz range)
• Internal Filter Network: Uses a proprietary design (detailed structure not disclosed) to effectively reduce noise entering the DAC

Detailed Specifications

• Model: CAD USB Filter
• Connectors: USB Type-B Male (connects to cable) + USB Type-B Female (connects to device)
• Function: Filters high-frequency noise on USB differential signals, ground, and +5V power lines
• Compatibility: Works with any USB audio cable
• Installation: Plugs directly into the USB-B input of a DAC / Streamer
• Applicable Systems: High-end digital audio, computer audio, streaming systems

Sound Quality and Performance

Using the CAD USB Filter can bring the following improvements to your system:

• Significantly improved clarity across all frequencies
• Wider and more dynamic soundstage
• More precise rhythm and timing (PRAT)
• Notes have more body and weight
• Quieter background, allowing details to emerge more easily
• More natural sound, less digital harshness
• Provides additional focus and musicality improvements, even when paired with high-quality USB cables

Especially suitable for systems connecting computers, music servers, and streamers to DACs, helping to reduce the impact of digital noise on sound.

Positive Online Reviews

• Hi-Fi+ (Alan Sircom): Reviewed the CAD USB Filter as an introductory device to CAD's philosophy, perfectly complementing high-end USB cables from other brands without diminishing their value, but rather adding significant benefits. Many users become CAD product supporters after trying it.
• Other reviews highlight its ability to improve clarity, soundstage scale, speed, and rhythmic performance. It shows noticeable effects even with excellent USB cables and is considered a practical and effective digital noise suppression accessory.