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Used, Good Condition • Professional AES Digital Output from PC via USB • Balanced Analog XLR I/O • Henry Engineering USB Matchbox Plus • Pro Audio

A hard-to-find practical solution to the need to get professional quality balanced audio in/out of a PC as well as giving a PC an AES digital output - with no need to take up an expansion slot. Item is in good cosmetic condition. Note that this device was manufactured when USB 2.0 was state of the art. So some current generation machines with very recent USB 3.X and USB-C ports may not be fully backwards-compatible (even if they claim they are). In that case you may need to add a simple plug in card with a USB 2.0 or earlier port to achieve compatibility - but that of course may not be possible with a laptop. Full product information is available at the link below

https://www.prostudioconnection.net/2509/USB_Matchbox_Plus_Manual_qr-code.png

Product Description

The USB Matchbox Plus from Henry Engineering is a professional USB-to-XLR bi-directional stereo audio converter that provides quality audio performance with the ease of USB connectivity in any application where digital audio from a computer needs to interface with a professional analog audio system. The unit is identical to the USB Matchbox but with the addition of peak level metering and a headphone amplifier.

Using a PC sound card to interface with a professional audio system usually leads to numerous problems. The inputs and outputs are often at the wrong levels. The unbalanced interface creates ground loops that cause hum and buzz. The USB Matchbox Plus solves the many of the problems caused by using computer sound cards in broadcast and professional audio environments and is USB powered.

Usually Sells for $500

The unit employs Burr Brown's Delta Sigma 8x over-sampling codec with SpAct audio clock recovery architecture. The codec's superb performance is further enhanced with proprietary L/C pre-filtering and analog circuitry designed by Bill Sacks, founder of Straight Wire Audio. This carefully tuned design eliminates the transient intermodulation products caused by inadequate reconstruction filters and yields ultra smooth, open and transparent audio with rock-solid bass and crystal-clear highs.

In addition, the unit's internal switch-mode power system virtually eliminates ground loops through the PC, allows operation at true professional levels with liberal headroom and can even surpass the quality of many 24-bit systems. MS-Windows and Linux OS are supported with no special driver or software needed. The USB Matchbox Plus will operate with virtually any audio editing, recording, or broadcast automation software at sample rates up to 48kHz and up to 16-bit resolution.

Features

Dual-PLL asynchronous design USB interface with simultaneous two channel record and playback
Front panel controls allow precise adjustment of input level and L/R balance trim
Output levels are calibrated with recessed trimmers
Servo-coupled reference-quality headphone amplifier
Input and output levels can be monitored using extended range LED meters which accurately indicate headroom relative to digital full-scale
Dedicated powered speaker output can be muted with an external contact closure via a Mute jack
The steel chassis provides effective RF shielding and all ICs that connect to the "outside world" are mounted in sockets
1/3 rack width and can be rack-mounted using an optional rack-mount shelf, or cabinet or wall mounted using optional cabinet/wall mounting brackets
USB bus powered