AudioQuest Jitterbug FMJ

The “full metal jacket” version of the popular USB filter and noise dissipation component

If you have a digital audio system, one of the easiest ways to make it more musical and detailed is to drop the noise floor on the various circuits. USB circuits, especially those on a laptop or low-end streamer can be extremely noisy and a great target for any kind of noise dissipation product.

The AudioQuest JitterBug is used by tens of thousands of audio enthusiasts in cars, on laptops, and computer-based audio streamers. The new FMJ takes it up a level by adding a significant reduction in environmental RF contamination to its famous in-circuit noise reduction capabilities.

The JitterBug can be used in series (inline) between, say, a laptop and a USB DAC, or it can be used in parallel or isolation, plugging into unused USB ports by itself to further drop noise. Deployed in isolation they can be used on routers, NAS drives, Roon Core computers, or on unused USB inputs on streamers to incrementally improve your system’s audio performance.

The new metal jacket is the most obvious change, but even the hinged output cover is made substantially from RF-absorbing carbon to improve performance as much as possible.

Using JitterBug with DragonFly

Connect a JitterBug FMJ in series with a DragonFly Black or Red and you will instantly hear a blacker background, and more microdetail. With Cobalt, however, try first. The Cobalt already uses some of JitterBug’s filtering, so using a JitterBug could hinder performance, notably if the USB port being used doesn’t supply a lot of current.

No matter what though, a second JitterBug in parallel is always a musical improvement as it pulls more RF Noise off the USB power bus. Be careful about connecting more than two to the same device, as the USB ports may share one bus, and three JitterBugs might pull too much current to be beneficial.

Features

• Dual-discrete noise-dissipation circuits reduce internally generated radio-frequency noise for improved streaming-audio performance
• Reduces jitter and packet errors
• Full-metal jacket protects against external noise
• Integrated RF-proof USB output plug further reduces noise
• Complies with all USB 2.0 specifications

JitterBug uses USB-A connections on both ends. When used in a car or on any device that has only USB-C connections, AudioQuest offers a super-compact high-performance C-male to A-female adaptor, and also the DragonTail flexible C-to-A adaptor (included with DragonFly Cobalt).