The Music Streamer from High Resolution Technologies (HRT) is an external D/A converter that connects between a computer and an audio system. This $99 device overrides the digital to analog (D/A) converter that's built into the computer, to provide improved audio reproduction of computer music files and streaming audio from Internet radio and sites like YouTube.

I listen to Internet radio while working, which means I do the majority of my music listening via computer, mostly with a circa 2003 iMac (and occasionally with a newer MacBook). Over the years, I've connected my computer to a plethora of audio systems, receivers, speakers and headphones in an effort to get the best sound from Internet radio, but had resigned myself to the fact that I was never going to enjoy high-quality music reproduction from low-bit-rate Internet radio stations, and compressed MP3 and AAC music files.

Since music is one of the most important things in my life (you too?), when I found out about the Music Streamer, I simply had to audition it. Measuring a compact 4.1 inches long by 2.1 inches wide by 1.2 inches high, the Music Streamer has a metallic red, solid-feeling metal casing and incorporates a built-in 16-bit D/A converter. The unit is powered by the computer's USB connection, and is USB 1.1-compatible.

Hooking up the device is simple--just connect a USB cable from one of your computer's USB jacks to the Music Streamer, and run a set of audio interconnects from its RCA jacks to any analog audio input, such as a line-level input of a receiver. My Macs immediately recognized the device, and once I went into System Preferences and switched the audio output of my computers from the Built-In Audio to the USB port, I was good to go. (I'm a Mac guy but I am told that setup with a PC is equally straightforward.)

Well. The aural improvement the Music Streamer provides over my iMac's built-in D/A is dramatic. Without the Music Streamer, the sound is spatially flat and seriously lacking in resolution and imaging--the music sounds like "sonic wallpaper." With the Music Streamer in place, the audio quality became so much better that it was one of the rare times in my 20-plus-year audio reviewing career that I was honestly and truly taken aback. Suddenly the music had presence and depth, and subtle details like reverb trails on vocals and instruments and low-level background sounds could be heard that were literally inaudible before. The sound went from bland and blah to having presence and a sense of tangibility to individual instruments and vocalists. Even when listening to my favorite Internet radio stations, 3WK Classic Underground Radio and 3WK Underground Radio which are streamed at only 96 kbps, the sound was transformed from being flat and "stuck to the speakers" to musically involving.

The improvement using my circa 2006 MacBook was nothing less than astounding. Through the stock audio output, the audio was grainy and, well, mediocre. With the Music Streamer connected, the sound was transformed from grungy to gratifying. Is it the sonic equivalent of a Meridian, Wadia, Audio Research, Cary Audio, Burmester or other high-end CD player or D/A converter? Of course not, but at $99 it doesn't pretend to be. (For $299, the HRT Music Streamer+ provides refinements like more upper midrange and high-frequency resolution, bass definition and soundstage depth.)

Will the Music Streamer work miracles on your computer's audio? I have no way of testing every computer out there, including models with high-performance sound cards, but if the improvement on my computers is any indication, I'm betting you'll hear a significant change for the better.

High Points
• In my testing, the HRT Music Streamer provided a dramatic improvement in computer music sound quality.
• The device is simple to connect to a computer-based audio system.
• It's compact, and easy to use with a desktop or laptop.

Low Points
• You can't connect an iPod directly to it--the Music Streamer doesn't have a dedicated iPod docking connector.
• It's plain looking--er, some would say homely.
• It's not an all-purpose D/A converter--you can only use it with the USB output from a computer, not with, say, the digital output of a CD player or transport.

Conclusion
The High Resolution Technologies Music Streamer is a compact outboard USB-compatible D/A converter that can be a boon to anyone who wants to enjoy good sound from computer music files and streaming audio. It made a major sonic improvement compared to my computers' stock D/A converters. I can now truly enjoy listening to music from my computers, and that's an improvement in my quality of life, not just in my audio gear.