Creatively Expandable
Echo III Rackmount
3-slot Rackmount Thunderbolt to PCIe Card Expansion System for Computers with Thunderbolt Ports
Sonnet Echo III Rackmount
Creatively Expandable
Echo III Rackmount
3-slot Rackmount Thunderbolt to PCIe Card Expansion System for Computers with Thunderbolt 4 or Thunderbolt 3 Ports
Sonnet Echo III Rackmount
Thunderbolt 3 Mac Computers

Connect Three Full-length PCIe Cards to Computers with Thunderbolt Ports

The best portable, mini desktop and all-in-one computers feature powerful CPUs and include high-performance Thunderbolt™ ports to support peripherals. But they lack the PCIe expansion slots creative pros need to install specialty adapter cards that enable their workflows by adding video and audio inputs, transcoding data, and connecting to high-speed shared storage and networks. Sonnet has a Thunderbolt solution — Echo™ III Rackmount — a professional Thunderbolt expansion system that allows you to connect up to three full-length (12.28 inches) PCIe cards simultaneously. Using a single Thunderbolt cable, it’s compatible with Apple M series Macs or Intel Macs with Thunderbolt 3 ports, as well as Windows or Linux computers with Thunderbolt 5 or Thunderbolt 4 ports.

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Thunderbolt Logo

The Thunderbolt Interface Connection

Three Slot Professional Desktop PCIe Card Expansion – when connected to one of your computer’s Thunderbolt ports, Echo III enables you to connect professional PCIe cards (three full-height, single-width cards, or one double-width card plus one single-width card).

iMac Pro Thunderbolt 3 Ports
Avid HDX, AJA Kona 5 & Sonnet Fusion Dual 2.5" SSD PCIe Cards

Supports Every Thunderbolt Compatible, Non-GPU PCIe Card

Video PCIe Card IconAudio PCIe Card IconSAS/SATA PCIe Card IconNetworking PCIe Card IconSSD PCIe Card Icon

Echo III Rackmount supports every Thunderbolt compatible, non-GPU PCIe 4.0, 3.0, 2.0, and 1.1 card available including video capture and transcoding; audio DSP; 6Gb or 12Gb SAS or SATA host bus adapter; 10Gb or 25Gb Ethernet; SSD storage; and other specialty types to your system.

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. 

PCIe Cards Compatibility PDF
Sound Mixer
Singer
Sound Mixer
Musicians
Avid Pro Tools Qualified
Ready for up to Three Pro Tools | HDX PCIe Cards – no Extra Parts Required

At the flick of a switch, the Avid qualified Echo III Rackmount system is instantly optimized to support up to three Pro Tools | HDX PCIe cards, with no extra parts necessary! This chassis has been tested and is qualified by Avid Audio group for use with Avid Pro Tools HD 2020 software, and Avid Pro Tools HDX and HD Native systems.

Avid Cards Installed In Sonnet Echo III Rackmount

Avid Pro Tools | HDX cards sold separately

Sonnet Echo III Rackmount Installed in Mobile Rack Kit

Your Entire Multi-card Pro Tools | HDX System in 4U Rack Space

Sonnet makes it easy to integrate a complete 2- or 3-card Pro Tools | HDX system and a Mac mini® in just 4U of rack space. With the rugged 1U RackMac mini rackmount enclosure plus the 2U Echo III Rackmount you can combine the power of HDX with any Avid Pro Tools hardware I/O for a complete system, including the exciting Pro Tools | MTRX Studio all-in-one audio interface.

Avid Pro Tools | MTRX Studio, Sonnet RackMac mini, PCIe cards, and mobile rack kit sold separately

Media Composer Icon

Avid Media Composer Qualified

Echo III Rackmount is separately qualified by the Avid Video group for use with Avid Media Composer/Symphony with many current and older Mac computers with Thunderbolt 3 and Thunderbolt 2 ports.

Sonnet Echo III Rackmount Front View
Ready for Additional Expansion

Key Features

Adds Connectivity and Capabilities Icon

Adds Connectivity & Capabilities

Connects up to three high-performance non-GPU PCIe cards to your computer lacking expansion slots via a Thunderbolt cable.

Avid Pro Tools | HDX Compatible Icon

Avid Pro Tools | HDX Compatible

HDX compatibility mode enables use of up to three Pro Tools | HDX PCIe cards with no additional parts needed.

Broad PCIe Card Compatibility Icon

Broad PCIe Card Compatibility

Every Thunderbolt compatible, non-GPU card supported regardless of length or height.

Three PCIe Slots Icon

Three PCIe 3.0 Slots

One x16 plus two x8 slots support three full-height, single-width cards, or one double-width card plus one single-width card.

Pro Power Icon

Pro Power

Integrated 400W power supply with 75W auxiliary power. Saves energy by powering on/off automatically with the computer.

Remarkably Quiet Icon

Remarkably Quiet

Dual temperature-controlled, variable-speed Noctua fans rated at 17dBA automatically and quietly cool the cards.

Thunderbolt Logo Icon

Thunderbolt to PCIe Device

Offers full PCIe bandwidth for the installed cards.

Two Thunderbolt Ports Icon

Connect Additional Thunderbolt Devices

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

Rugged 2U Steel Rackmount Housing Icon

Rugged 2U Steel Rackmount Housing + Optional Expansion Space

Provides robust and secure protection in server and DIT racks; space for an additional Sonnet expansion module (sold separately).

Apple logo icon.

Mac Compatible

Supports all M series Macs and Intel Macs with Thunderbolt 3 ports.

Windows logo icon.

Windows Compatible

Supports Windows computers with Thunderbolt 5 or Thunderbolt 4 ports.

Linux logo icon.

Linux Compatible

Supports Linux computers with Thunderbolt 5 or Thunderbolt 4 ports.

Free lifetime tech support icon.

Sonnet 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.

Sonnet Echo III Rackmount Module & Chassis

Three PCIe 3.0 Slots Plus Power to Spare

Echo III Rackmount features one x16 and two x8 PCIe 3.0 slots, enabling it to support a wide variety of cards at the same time. It integrates a universal 400W power supply, plus a 75W auxiliary power connector to support especially power-hungry non-GPU cards, including the Avid Pro Tools | HDX. Echo III was designed without a power switch, because it powers on and off automatically with the connected computer, saving energy in the long run. With no power switch, you can’t forget to turn off the system!

Sonnet Echo III Rackmount Interior
Full-length PCIe Card Illustration
Low-profile PCIe Card Illustration
75W Auxiliary Power Connections Illustration
Sonnet Echo III R Interior Cooling

Built for Cool, Rackable Expansion

Echo III Rackmount mounts in a rack space 2U tall, and is only 16.5 inches deep, making it ideal for use in mobile racks, carts, rack cases, and server rooms. Its enclosure is formed of heavy-duty steel to provide secure mounting for the Echo III module and protection for the PCIe cards installed inside, and to support maximum airflow for cooling, regardless of where you install it in a rack.

Sonnet Echo III Rackmount with PCIe CardsSonnet Echo III Rackmount with Avid Cards
Echo III Rackmount accommodates the PCIe cards you need for your workflow, ranging from the largest video I/O and audio transcoding cards, to the smallest Ethernet NIC and USB interface cards
Sonnet Echo III Rackmount Installed in Rack Rails

Rack Steady

Echo III Rackmount’s included adjustable rackmount extension rails enable the 2U enclosure to be installed securely in a variety of racks from 16 to 24 inches deep.

Noctua FanNoctua Fan
Rated 17.1 dBA Icon

Dual Fans. Ultra-quiet Operation.

Featuring dual Noctua fans, Echo III Rackmount is designed to deliver ultra-quiet operation so that it can be comfortably used in noise-sensitive environments. Rated at 17.1dBA — below the 20dBA ceiling prescribed for use in recording and broadcast studios — the fans spread their noise spectrum to minimize any single frequency’s impact. To further ensure negligible noise levels, the fans are temperature-controlled, automatically speeding up and slowing down smoothly as needed, and the enclosure is engineered to optimize airflow over the installed cards to effectively and efficiently cool the system.

Noise Levels Comparison Chart
Comparative examples of noise levels source: iacacoustics.com
Sonnet Thunderbolt cable and 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 cable lock, that prevents accidental cable disconnections.
Sonnet Thunderbolt cable with ThunderLok sitting beside it.
Thunderbolt port with threaded hole icon.

ThunderLok Advantage

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

Thunderbolt Optical Cables Installation Illustration

Get Full Thunderbolt Performance, at a Distance

Whether noisy PCIe card fans make it impractical to use Echo III Rackmount in a noise-sensitive environment, or because securing it in another room is required, you may find it necessary to put some space between the chassis and computer. No problem! Thunderbolt optical cables (sold separately), available in lengths from 5 to 50 meters, enable you to locate your equipment where you need and connect the pieces without loss of functionality. These thin, lightweight, and tough fiber optic cables are easy to route, and support high-speed data transmission equal to copper Thunderbolt cables.

Thunderbolt Optical Cables

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.
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

Designed for the Fastest Connection to Thunderbolt Computers

Echo III is 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.
Sonnet Echo III Desktop

Desktop Version Available

Choose between Echo III Rackmount and Echo III Desktop to suit your workflow needs. Echo III Desktop is wrapped in a rugged, yet lightweight aluminum outer shell, resulting in a system light enough to carry without weighing you down, yet sturdy enough to securely protect the installed PCIe cards.

Echo III Rackmount Thunderbolt Expansion System