// 9TO5MAC — MOBILE & WEB

Hands-On: Sonnet Echo 21 Thunderbolt 5 SuperDock – a significant speed boost [Video]

Published: 08/26/2026, 02:06 PM

The Sonnet Echo 21 Thunderbolt 5 SuperDock, the follow-up to the similarly named Echo 20 Thunderbolt 4 SuperDock (review), lets you add tons of I/O to your Mac via a single Thunderbolt cable, and brings several noteworthy improvements for those looking to upgrade or future-proof their Mac setups. Perfect for both laptops like the MacBook Pro, and desktop machines like the just-announced M5 Pro Mac mini, the Echo 21 SuperDock adds a vast array of I/O to these machines. Watch our full hands-on video walkthrough for the details, and be sure to subscribe to 9to5mac on YouTube for more. Jeff's favorite screen cleaning cloth that polishes to a shine. How does the Echo 21 Thunderbolt 5 SuperDock compare to its direct predecessor? If you were just to take a quick glance, you’d be hard-pressed to tell the difference between the two. The design, form factor, color, and virtually everything else about these two devices look the same. But upon closer inspection, it’s clear the Thunderbolt 5 SuperDock adds a helping of new features to enhance workflows. The most noteworthy benefit of the Echo 21 over its predecessor is that all Thunderbolt ports have been upgraded from Thunderbolt 4 to Thunderbolt 5. This is a substantial upgrade, as Thunderbolt 5 supports double the bandwidth of Thunderbolt 4, increasing from up to 40 Gbps to up to 80 Gbps of bidirectional data. You’ll notice the difference when transferring data between both the internal and externally mounted SSDs if connected to a Thunderbolt 5 machine. Thunderbolt 5 connectivity also supports Bandwidth Boost, which dynamically reallocates some downstream lane capacity to the upstream lane when necessary. Under certain conditions, this reallocation may peak at up to 120 Gbps on the upstream side. This dynamic bandwidth allocation enables connecting to displays with high resolutions and refresh rates that require extra throughput. Jeff Benjamin's favorite screen cleaner for Apple products. One interesting thing that eagle-eyed users will notice is that there are actually four ports listed in System Information for the dock’s Thunderbolt 5 controller. Port A is the upstream port to the host computer, and ports B and D are the downstream ports. So, where does that leave Port C? That particular port, although not tied to a physical USB-C connection, is used for the DisplayPort/HDMI output. Notably, Sonnet adds a full-size DisplayPort connection to the Thunderbolt 5 SuperDock, a feature not available on the Thunderbolt 4 version. It means the dock can now connect to a display via Thunderbolt/USB-C, HDMI, or DisplayPort. Note that you can use only HDMI or DisplayPort; it’s either/or, not both, and HDMI takes precedence when both are connected. When connecting via HDMI, connectivity tops out at 4K60, so I recommend using DisplayPort, which supports up to 4K144. If you’re looking for the most capable connectivity option, use Thunderbolt, which supports a wider range of resolutions and frame rates. Because Thunderbolt 5 has a minimum mandatory power delivery requirement of 140W, it can deliver full power to a power-hungry machine like the 16-inch MacBook Pro, while the Thunderbolt 4 version of the dock was limited to 100W. This change also means that the power adapter that drives the dock is now larger and rated for higher power: 20V at 12A vs 20V at 7.5A.