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Sonnet Echo III Rack-Mount 3-Slot Thunderbolt 3 to PCIe Card Expansion System

3-slot rack-mount Thunderbolt 3 to PCIe card expansion system


Product Description

Plugged into one of your computer’s Thunderbolt 3 ports, the Sonnet Echo III Rack-Mount system delivers 2750 MB/s of PCIe bandwidth and enables you to connect professional PCIe cards (three full-height, single-width cards, or one double-width card plus one single-width card).

Supports Every Thunderbolt 3 Compatible, Non-GPU PCIe Card

Echo III Rackmount supports every Thunderbolt 3 compatible, non-GPU PCIe 1.1/2.0/3.0 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? Sonnet have put together a compatibility list that identifies cards conforming to Thunderbolt technology requirements, and organized by fit and power compatibility with specific expansion systems.

Avid Pro Tools Qualified

Sonnet Echo III is 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 Rack-Mount 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.

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.

Three PCIe 3.0 Slots Plus Power to Spare

The Echo III Rack-Mount 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. The 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!


  • Connects up to three high-performance non-GPU PCIe cards via a Thunderbolt 3 cable to your computer lacking expansion slots
  • HDX compatibility mode enables use of up to three Pro Tools | HDX PCIe cards with no additional parts needed
  • Every Thunderbolt 3 compatible, non-GPU card supported regardless of length or height
  • One x16 plus two x8 slots support three full-height, single-width cards, or one double-width card plus one single-width card
  • Integrated 400W power supply with 75W auxiliary power - saves energy by powering on/off automatically with the computer
  • Dual temperature-controlled, variable-speed Noctua fans rated at 17dBA automatically and quietly cool the cards
  • Offers 2750 MB/s of PCIe bandwidth for the installed cards
  • One port connects to computer; second port supports daisy-chaining of up to five additional Thunderbolt peripheral devices
  • Provides robust and secure protection in server and DIT racks; space for optional future expansion

Product Specifications

Condition New
Package Contents Echo Express III Rack-Mount, power cord, Thunderbolt 3 (40Gbps) cable, two ThunderLok 3 connector retainer clips, and documentation
Width 19 in
Depth 16.6 in
Height 3.6 in
Unit Weight 23.1 lb
Chassis 19-inch Rack-mount

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I would like to thank VK for the wonderful sales assistance, service and prices. This was my first purchase with you and it won't be my last. I only wish I'd discovered you years ago!
Matthew R.
I had two Grammy wins this year - Ray LaMontagne & Carolina Chocolate Drops. Both made with help from Vintage King!
Ryan F.
In almost 20 years in Pro audio buying, never did I receive a unit so well packed and exactly as described. Works flawlessly. The whole process has been so smooth. I will never hesitate to do business with you guys in the future and will recommend you to everyone I know.
Martin C.
This was my first experience buying something from Vintage King (although I surf the "used" categories on the website frequently!), and, despite being on the other side of the world, I had absolutely no trouble and everything went very smoothly.
Phil T.
The speed of delivery exceeded my expectations! I was VERY pleased that my shipment arrived in time for a scheduled vocal tracking session. The packing insured that my order arrived safely. And the sales staff responded quickly to questions regarding the product.
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