Echo Express SEL - Compact Desktop Thunderbolt Expansion System for One Low-profile PCIe Card
Low-profile.
Pro Performance.
Low-profile. Pro Performance.

Echo Express SEL

Compact, Desktop 1-slot Thunderbolt to PCIe Card Expansion System for Computers with Thunderbolt Ports

Connect a Low-profile PCIe Card

The latest ultra-light notebooks, small form factor, and all-in-one Mac®, Windows®, and Linux® computers with Thunderbolt™ ports are amazingly thin, but there’s nowhere to install PCIe cards. What if you want to add video capture, processing, or connecting capabilities to your computer? Sonnet has the answer – Echo™ Express SEL is a compact, desktop Thunderbolt™ Expansion System that enables you to connect a low-profile PCIe card to your computer via a single Thunderbolt cable.

Thunderbolt Logo

The Thunderbolt Interface Connection

Small and Mighty – when connected to one of your computer's Thunderbolt ports, Echo Express SEL allows you to connect a  low-profile PCIe card, such as Fibre Channel, Ethernet, video capture and processing, SAS and SATA host bus adapter, or a RAID controller. Watch this video to learn more about the performance benefits of the Thunderbolt controller in Sonnet Thunderbolt products.

Key Features

Connects a PCIe Card Icon

Connects a PCIe Card

Use a high-performance PCIe card with any computer with Thunderbolt ports.

One PCIe 3.0 x8 Slot Icon

One PCIe 3.0 x8 Slot

Supports one low-profile PCIe card.

Thunderbolt Logo Icon

Thunderbolt to PCIe Device

Offers full PCIe bandwidth to the installed card.

Small Package, Full Performance Icon

Small Package. Full Performance.

Smallest Thunderbolt Expansion System; supports the most popular low-profile, Thunderbolt-compatible PCIe cards at full performance.

Two Thunderbolt Ports Icon

Connect Additional Thunderbolt Devices

One port connects to computer; second port supports daisy-chaining additional Thunderbolt peripheral devices.

Remarkably Quiet Icon

Remarkably Quiet

Temperature-controlled, variable-speed fan automatically and quietly cools the card.

Energy Saver Mode Icon

Energy Saver Mode

Powers on/off automatically with the computer.

Rugged Aluminum Housing Icon

Rugged Aluminum Housing

Provides robust and secure protection.

Power for Peripherals Icon

Power for Peripherals

Daisy chain port provides up to 15W of power to connected peripherals.

Apple M Series CPU Icon

Apple® M series Compatible

Supports M series Macs (with PCIe cards that have compatible drivers).

Intel Mac and Windows Compatible Icon

Intel® Mac & Windows Compatible

Supports Intel Macs with Thunderbolt 3 ports and Windows computers with Thunderbolt 5, 4, or 3 ports.

Linux Compatible Icon

Linux Compatible

Supports Linux computers with Thunderbolt 4 and Thunderbolt 3 ports.

Free Lifetime Tech Support Icon

Free Lifetime Tech Support

Founded in 1986 in Orange County, Southern California — the vibrant hub of technology and engineering south of Silicon Valley — Sonnet has been at the forefront of innovation. Over the years, we've developed numerous award-winning products that enhance performance and connectivity for Mac, Windows, and other industry-standard computers. Many of our team members have been with us for over two decades, providing us with extensive expertise about our current and past offerings. If you ever need technical support for any of our products, don’t hesitate to reach out; we’re here to assist you.

Low-profile PCIe Cards

Nearly Every Thunderbolt-compatible, Low-profile PCIe Card Supported

Echo Express SEL accommodates a wide variety of PCIe cards. Do you have a card in mind but aren’t sure it’s compatible? We’ve put together a compatibility list that identifies cards conforming to Thunderbolt technology requirements, and organized by fit and power compatibility with specific expansion systems. 

Echo Express SEL Icon

Smart Design, Inside and Out

Aluminum Enclosure. Auto Power On/Off.

With a shell crafted of rugged and lightweight aluminum, Echo Express SEL securely houses the installed PCIe card. Inside, the card is protected through the use of a variable-speed, temperature-controlled fan which ensures the card and chassis’ components remain reliably cool. The fan automatically speeds up as necessary to cool the card when it’s hot, and slows down when it’s cool. Since Echo Express products automatically power on and off with your computer, there is no power switch on the chassis, ensuring you don’t waste energy by forgetting to turn it off.

Designed for Low-profile PCIe Cards

Echo Express SEL supports one half-length (up to 6.6 inches long), low-profile, single-width PCIe card; PCIe 4.0, 3.0, 2.0, and 1.1 PCIe 4.0 cards are supported. Many of the most popular Thunderbolt-compatible high-speed networking and storage controller cards are a perfect fit, and even the BlueFish 444 Epoch 4K Neutron video card can be accommodated.

Echo Express SEL PCIe Card Size Support
Echo Express SEL Interior View

1. PCIe 3.0 x8 slot

Fan Icon

Quiet Please

Echo Express SEL is designed to be ultra-quiet so that it can be comfortably used in noise-sensitive environments. The airflow path within the chassis has been specially designed to enable the fan to quietly and efficiently cool the installed card at all times, even during peak operation.
Sonnet Thunderbolt Cable & ThunderLok Icon
Secure Connections for High Performance

Thunderbolt Cable and ThunderLok Included

Sonnet includes a Thunderbolt cable that supports Thunderbolt’s maximum bandwidth and is fully compatible with Thunderbolt 5, 4, and 3 computers. Sonnet also provides ThunderLok,™ a Thunderbolt connector retainer clip, that prevents accidental cable disconnections.
Sonnet Thunderbolt Cable with ThunderLok
Thunderbolt Port with Threaded Hole Icon

ThunderLok Advantage

Many Sonnet Thunderbolt products featuring Thunderbolt ports come equipped with threaded mounting holes to securely attach Sonnet ThunderLok retainer clips, preventing Thunderbolt cables from accidentally disconnecting.

Thunderbolt Technology

Fastest External Interface Available

Sonnet Thunderbolt products feature a high-speed Thunderbolt interface that delivers PCIe bandwidth needed to support data transfers at full speed.

Two Thunderbolt Ports Icon
Connect Additional Thunderbolt Devices
One port is reserved for connecting to your computer; the second port enables connection of additional Thunderbolt peripheral devices in a daisy chain.
10Gbps USB 3.2 Gen 2 Icon
10Gbps USB 3.2 Gen 2 Support
10Gbps USB 3.2 Gen 2 support allows you to connect a USB device to the second Thunderbolt port using the proper cable or adapter.
15W Power Icon
Provides 15W of Power
For peripherals requiring extra power, 15 watts is provided to bus-powered devices through the secondary Thunderbolt port.
8K Display Icon
Supports Connecting Up to One 8K Display
Maximize the utilization of one computer Thunderbolt port, connecting the largest display supported by your computer.
Thunderbolt 4 Computers

Compatible with the Latest Thunderbolt Computers and Apple M series Macs

Echo Express SEL is fully compatible with the latest Thunderbolt computers, including Apple M series Macs. Sonnet Thunderbolt expansion systems are purposely designed with a Thunderbolt 3 controller and its four lanes of PCIe (not available in a Thunderbolt 4 peripheral) to achieve maximum simultaneous ingest speeds. Watch this video to learn more about the performance benefits.
Apple M Series CPU

Compatible with Apple M series Macs

see Tech Specs for details

Older Macs with Thunderbolt 2 Ports

Backward Compatible with Older Macs

Echo Express SEL is also compatible with Macs with Thunderbolt 2 or Thunderbolt 1 ports when used with the bi-directional Apple Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter and a Thunderbolt cable (both sold separately).

Echo Express SEL Thunderbolt Expansion System