Harman's new Signal Doctor technology, announced at CES 2014 restores vibrancy to compressed digital audio tracks. by Wayne Cunningham January 8, 2014 5:43 PM PST Harman created this chart, showing how much Signal Doctor processes music depending on bitrate. (Credit: Harman) LAS VEGAS--The connected car brings many advantages to the driver, but will also mean degraded music quality as people increasingly use streaming audio services. At CES 2014, Harman announced Signal Doctor, a digital signal processor technology which attempts to restore fidelity to compressed audio. Typical digital audio tracks bought from Amazon and iTunes are compressed to 128 or 256 kbps, and streaming audio from the like of Pandora and Spotify is often down to 64 or 96 kbps. That much compression means a lot of lost information from a music track, which diminishes the sound quality. Signal Doctor analyzes the audio signal in real time, and attempts to predict and restore the part of the signal that was lost. The technology restores peak levels and high frequencies, all of which compression technology tends to discard. It also isolates vocals and enhances them. During a demonstration at CES 2014, Harman played a variety of low bitrate tracks, including AC/DC's Back in Black and Sarah MacLachlan's Building a Mystery, using a graphic audio analyzer to show where compression had cut off the frequencies. When the Signal Doctor bypass was switched on, areas that appeared flat on the original graphic analysis were filled in. The listening experience was greatly improved. The unprocessed compressed tracks often sounded muffled and lifeless. Signal Doctor added richer tones to the music. When played in a Kia Sorento, the soundstage for the music widened considerably. Signal Doctor is a software algorithm which Harman can load into digital signal processor hardware. It dynamically scales itself depending on how much music is compressed, applying its full capability to the most compressed music, and letting uncompressed audio, such as from a CD, play through without interference. Currently, the Signal Doctor technology is available in the JBL Authentics powered speaker line-up. Harman, as a major automotive supplier, will also make the technology available to automakers.
Harman's new Signal Doctor technology, announced at CES 2014 restores vibrancy to compressed digital audio tracks.
Harman created this chart, showing how much Signal Doctor processes music depending on bitrate.
(Credit: Harman)
LAS VEGAS--The connected car brings many advantages to the driver, but will also mean degraded music quality as people increasingly use streaming audio services. At CES 2014, Harman announced Signal Doctor, a digital signal processor technology which attempts to restore fidelity to compressed audio.
Typical digital audio tracks bought from Amazon and iTunes are compressed to 128 or 256 kbps, and streaming audio from the like of Pandora and Spotify is often down to 64 or 96 kbps. That much compression means a lot of lost information from a music track, which diminishes the sound quality.
Signal Doctor analyzes the audio signal in real time, and attempts to predict and restore the part of the signal that was lost.
The technology restores peak levels and high frequencies, all of which compression technology tends to discard. It also isolates vocals and enhances them.
During a demonstration at CES 2014, Harman played a variety of low bitrate tracks, including AC/DC's Back in Black and Sarah MacLachlan's Building a Mystery, using a graphic audio analyzer to show where compression had cut off the frequencies. When the Signal Doctor bypass was switched on, areas that appeared flat on the original graphic analysis were filled in.
The listening experience was greatly improved. The unprocessed compressed tracks often sounded muffled and lifeless. Signal Doctor added richer tones to the music. When played in a Kia Sorento, the soundstage for the music widened considerably.
Signal Doctor is a software algorithm which Harman can load into digital signal processor hardware. It dynamically scales itself depending on how much music is compressed, applying its full capability to the most compressed music, and letting uncompressed audio, such as from a CD, play through without interference.
Currently, the Signal Doctor technology is available in the JBL Authentics powered speaker line-up. Harman, as a major automotive supplier, will also make the technology available to automakers.
