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CAD · Noise Reduction
$825
Not currently in our rooms. For a serious buyer we will often bring a piece in from the manufacturer for a private session — tell us about your system and what you are weighing it against, and we will advise.
CAD · Noise Reduction
A thumb-sized plug that goes into any spare USB port and reduces high-frequency noise on the port's 5 V and signal-ground lines, from kHz into the GHz range.
Price is for one USB Control. No cable is needed; it plugs straight into the component.
Authorized CAD dealer · Delivery and installation by Pearl Audio · Trade-ins welcome
The story
Nearly every modern audio component has a USB port it does not use for music: a software-update socket on a DAC or streamer, a spare port on a server, router or switch. Those ports share the component's 5 V supply and its signal ground, and Computer Audio Design's position is that they are an open door for high-frequency noise. The USB Control is a passive device, developed from the materials and research behind the Ground Controls and the 1543 DAC, that plugs into such a port and absorbs that noise, converting it to heat.
It is a USB A plug in an acrylic body, 58 mm long and 15 g, with no cable and no power. It can be inserted or removed with the component running, which makes the comparison easy. CAD suggests music servers, routers, network switches and digital interfaces as the first places to try it, and more than one can be used in a system. Isabel Whitley of CAD notes that it works particularly well with Linn streamers, where the service USB port is usually free.
The Ear gave the USB Control a Best Buy award and listed it among its best products of 2024; Roy Gregory at GY8 and Alan Sircom at hi-fi+ reviewed it in 2023 and 2024. At $825 it is the least expensive way into CAD's approach, and a useful test of whether grounding and noise reduction matter in your system before committing to a Ground Control.
| Type | Passive USB noise reduction device |
| Connector | USB A plug |
| Noise range | kHz into the GHz range (CAD) |
| Dimensions (H × W × D) | 12 × 24 × 58 mm (0.5 × 0.9 × 2.3 in) |
| Weight | 15 g (0.5 oz) |
| Power | None required |
| Warranty | 2 years |
| Made in | United Kingdom |
The USB Control is the least expensive CAD product and the one to try first; the Ethernet Control treats the network connection and the Ground Controls treat the signal ground.
Several USB Controls can be used in one system, one per spare port.
Plan your CAD system with Pearl Audio
Pearl Audio is an authorized CAD dealer. Tell us which components have a spare USB port and we will advise where to start, or arrange an audition in our Portland showroom. Call (503) 222-2599 or email sales@pearlaudio.com.
The Pearl Audio experience
A system at this level should be heard, thoughtfully matched, and properly set up. From the first audition to long-term ownership, you work with the same people, in person.
The CAD USB Control is not in our rooms at present. When it is the right piece for a client we arrange a demonstration unit from the manufacturer and set it up for a private session.
We deliver and install throughout the Portland area, taking care of placement, connections, ventilation and system configuration ourselves.
We support everything we sell for as long as you own it, whether the answer comes by phone, in your home, or through factory service.
Trade-in assistance and qualifying 100% Trade-Up options give you flexibility when your listening priorities or your system change.
