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  • Automatic Chord Detection

    Chord Detection is another new major feature found in Song Surgeon Version 5. As a file is opening in Song Surgeon, the program analyzes the frequencies of the audio and determines and displays the chords it finds. This new feature was one of the most requested features from our user base, and many customers will find in useful.

    Ten years ago when Song Surgeon was first launched key detection was being worked on but wasn’t very good. At that time the best available product could detect key accurately about 35% of the time. The technology has improved and the accuracy increased substantially, in fact, the accuracy statistics have been reversed. Today the accuracy is in the 70-80% range.

    As you can see in the graphic below the chords it detects are displayed in “bubbles” below the wave form graph.

    When the audio file being analyzed consists only of a single instrument, like a guitar or piano that the accuracy of the chord detection is very high. However, most music is polyphonic. It has guitars, drums, keyboard, bass, vocals and often much more. While the accuracy in such cases in lower, it is still very good.

    Immediately below is a time – chord correlation chart for the song Hotel California. The accuracy of the chord detection in this song is very good. What is shown below are the correct chords as determined by a professional guitar player vs. what was detected by Song Surgeon. Song Surgeon missed only 3 chords completely (highlighted in red) and it was close but not exactly correct on 27 more (e.g. Actual chord was E, detected was E7) and the remaining 94 were detected accurately.

    Time 0.371519 3.57587 6.87311 10.1239 10.8205 13.3283 16.579 19.8763 23.0806
    TRUE Bm F#7 Asus2 E9 G D EM F#
    SS Value Bm F#7 A E Bm G D Em7 F#7
    Time 26.285 29.5822 32.833 36.0838 39.2417 42.4925 45.8362 49.1334 52.3378
    TRUE Bm F#7 A E7 G D Em F#7 Bm
    SS Value Bm F#7 A E7 G D Em7 F#7 B
    Time 53.6845 58.7 62.0437 65.0159 66.6413 71.7497 73.8395 75.0005 77.8797
    TRUE F#7 A E9 G D Em7 F#7 F#7 Bm
    SS Value F#7 A/E E7 Gmaj7 D Em7 Bm F#7 Bm
    Time 81.502 84.7528 88.0036 91.208 94.4123 97.756 100.96 104.304 107.601
    TRUE F#7 A E G D Em7 F# G D
    SS Value F#7 A E G D Em7 F#7 G D
    Time 110.852 114.01 117.354 120.651 124.041 127.06 130.171 133.329 136.812
    TRUE F# Bm G D Em F# Bm F# A
    SS Value F#7 Bm7 G D Em F#7 Bm F#7 A
    Time 140.035 143.035 146.379 149.862 153.066 156.317 159.614 162.725 166.069
    TRUE E G D Em F# Bm F#7 A E
    SS Value E Gmaj7 D Em F# Bm F#7 A E
    Time 169.32 172.292 175.868 179.072 182.323 185.481 188.871 192.029 195.326
    TRUE G D Em F#7 G D F# Bm G
    SS Value Gmaj7 D Em F#7 G D F#7 Bm7 G
    Time 198.577 201.967 205.172 207.772 211.487 214.738 218.035 220.915 224.537
    TRUE D Em F# Bm F#7 A E9 G D
    SS Value D Em F# Bm F#7 A6 E7 Gmaj7 D
    Time 227.741 231.039 233.361 237.494 240.419 244.042 246.921 250.404 253.841
    TRUE Em F# Bm F#7 A E G D Em
    SS Value Em7 F# Bm F#7 A E G D Em
    Time 256.998 259.831 263.5 266.426 270.187 273.299 276.317 279.847 283.005
    TRUE F# Bm F# A E G D Em F#
    SS Value F#7 Bm F# A6 E7 G D Em F#
    Time 286.023 289.553 292.339 296.24 299.259 302.045 305.714 308.965 312.123
    TRUE Bm F# A E G D Em F# Bm
    SS Value Bm F# A6 E7 G D Em7 F#7 Bm
    Time 315.327 318.624 321.736 324.011 325.219 327.262 331.767 335.018 338.222
    TRUE F# A E G D Em F# Bm
    SS Value F# A E7 F#m7b5/E Gmaj7 D Em F# Bm
    Time 341.566 344.77 347.928 351.271 354.476 357.773 360.977 364.135 367.479
    TRUE F# A E G D E F# Bm F#
    SS Value F# A E7 G D Em F# Bm F#
    Time 370.451 374.027 377.185 380.25 383.687 386.937 390.142
    TRUE A E7 G D Em F#
    SS Value A E7 G D Em F# N
    • 3 Wrong

    • 27 Almost Right, E vs. E7

    • 94 Exactly Correct

    If you’d like to learn more about the Chord Detection feature found in Song Surgeon please review the User Guide and/or the Training Videos which discuss and demonstrate how this works in more detail.

    If you are interested in buying, or if you’d like to take our fully functional free demo for a test drive, please click the appropriate red button near the top, right side of this page.