Tag Archives: Chord Tracker

Review: zplane deCoda

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A recent thread on the Keyboard Forum (“What was the first song you figured out by ear?”) brought up memories of high school and combo organs. One of the most popular tunes of the time was “Space Rock Part 2” by The Baskerville Hounds. Air play on Ghoulardi was a big boost to its popularity and it really brought people onto the dancefloor. “Space Rock” is pretty much a rip of The Stones’ “2120 South Michigan Avenue,” albeit way up-tempo than the Stones’ version. Sly Stone knocked out his own titled “Buttermilk.” If you’re wanting a modern update, listen to the 2015 Jerry Cortez cover.

The “Space Rock” organ solo was the solo to know as a teen. At the time, I was paying off my Farfisa and didn’t have any money for records, so the old “drop the needle until you got it” method wasn’t for me. My bandmates were always on my back about it and they didn’t accept my “Guys, they’re just jammin'” excuse. I tried to cover the head and then improvise. Oh, well.

I’m pulling together a backing track for “Space Rock/2120” and it seemed like the time to transcribe the solo. Enter zPlane deCoda. In a nutshell, zplace have deployed their time/pitch stretching and DSP expertise to the problem of picking out tunes from audio. (See the Sound On Sound review for more information.) It’s not an audio-to-MIDI converter, so you still need to use your ears and eyes.

First, ya drag (or open) an audio file in deCoda. deCoda gives you two views: a standard (amplitude) waveform view of the audio and a spectrographic plot. The spectrographic plot is like a DAW piano roll. Instead of notes, however, it displays the sonic energy present at each pitch. You can (kind of) see the notes in the song — pitch and duration. I spent most of my time in the spectrographic display.

zplane deCoda in action

Optionally, you can turn on an XY panel (at right in the image above) that lets you focus playback and analysis on a particular “region” of the stereo field and audio frequency spectrum. Thanks to the XY panel, you can eliminate the bass and high-end sibilance. Blobs light up in the XY panel during playback as notes come and go.

deCoda offers a number of playback controls. You can playback at 1/4, 1/2, 3/4 and full speed. You can transpose up and down. You can change the tempo. My recommendation is to get the best mix of key, tempo and XY region before deep diving transcription.

Like Yamaha’s Chord Tracker, deCoda discovers key, tempo, chords and song sections. As mentioned, you can modify deCoda’s decisions. Compared against Chord Tracker, I would give Chord Tracker the edge. (Yamaha have invested a pile ‘o’ cash into music analysis.) Both tools handle simple chords OK, but forget jazz chords (no 11th and 13th chords) or gospel voicings.

After quickly munching “Space Rock”, deCoda had the key right, but half the actual tempo. The Hounds played “Space Rock” at a blistering 156 BPM. deCoda says 78 BPM. That’s OK, but…

One of the coolest deCoda features is the ability to draw notes on top of the spectrographic display. The notes play back through a simple synthesizer (think Casiotone). A mixer controls the relative level of song audio and synthesized tones. Once I got a little more skilled with deCoda, I found myself changing the relative levels quite often in order to A/B the original audio and the drawn notes. I wish deCoda offered a few different synth voices as the simple tones blended with the organ notes making it difficult to sort out the sounds by ear.

With a little practice, you can begin to pick out the notes by sight as well as ear. 1/4 playback is good for checking note start and duration. “Space Rock” is a mono mix and a mess of frequencies with that danged 60’s ring-y reverb. Thus, there are many false positives — places where you think there is an organ note, but it’s actually the frapping guitar. I wish deCoda could color notes according to timbre. Man, that would be quite the time-saver.

To compensate, I found myself playing the notes on keyboard, mainly to check fingering. “Space Rock” is one of those lazy blues tunes where the keyboardist just rocks his or her fingers around in one basic hand position. It’s difficult to read piano roll notes in real-time; I’d love to have even a simple staff viewer.

Now for the “but…”. deCoda can export the notes as a Standard MIDI File (SMF). Very good. deCoda produces MIDI notes that follow the identified tempo. When the SMF is imported into a DAW or notation tool, it arrives with the identified (or tweaked) tempo. Note play back sounds right, but if you change to the correct tempo in the tool, note starts and note durations are off (i.e., half of what they should be). I had to fix the note starts and durations in Sonar, save another SMF and import the modified SMF into Sibelius. Bummer.

I discovered the tempo and note export gotcha downstream. I also found that I wanted to work and play in G Major, not F# Major, AKA “that frapping guitar key.” I had already started a draft in Sibelius and it became a question of how much work I wanted to throw away. It’s better to get these considerations right from the start before export and downstream work.

Speaking of Sibelius, I really longed to have the identified notes in notation form, not piano roll. Under Windows 10, I couldn’t work in Sibelius and deCoda simultaneously. They did not work together — some kind of MIDI or audio system conflict. One or the other tool wouldn’t play when they were both open at the same time. In a few cases, I had to resort to notation paper and pencil to transfer identified notes into Sibelius, exit Sibelius, then re-start deCoda. Painful.

After all is done, I arrived at a decent transcription in Sibelius. (See image below; click to enlarge.) After seeing and playing the solo against a rough backing track, I think deCoda is about an eighth to a quarter note ahead of the beat. I’m not sweating it too much as playing “Space Rock” comes down to feel. However, it might be a factor when an accurate score is needed for chart-driven players.

Space Rock Part 2 (solo)

zplane deCoda is a worthwhile tool. It won’t automatically transcribe, but it is a decent assistant. The note editor and MIDI export are a real boon as I a keep a book of charts for reference. The XY plot is also a worthy mix visualization tool and has been repurposed in zplane peel. I hope that deCoda continues to invest in deCoda as I would love to have timbre coloring. That’s a tough technical problem, but cracking that nut would put zplane way out in front competetively.

Copyright © 2021 Paul J. Drongowski

Yamaha CSP pianos: First take

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Yamaha just announced the Clavinova CSP series of digital pianos. There are two models: CSP-150 and CSP-170. The main differences between the 170 and 150 are keyboard action (NWX and GH3X, respectively) and sound system (2 x 45W and 2 x 30W, respectively). USA MSRP list prices are $5,399 to $5,999, and $3,999 to $4,599 USD.

These are not stage pianos. They are “furniture” pianos which complement and fit below the existing CLP line.

Here’s my imagined notion of the product pitch meeting:

Digital piano meets arranger meets Rock Band. Let’s say that you don’t have much (any) musical training, but you want to play along with Katy Perry. Sit down at the CSP with your smart device, install the Smart Pianist app and connect via Bluetooth. Call up “Roar” in the app and get a simple musical score. Start the song, follow the LEDs above the keys and play along with the audio. The app stays in sync with the audio and highlights the notes to be played on each beat. So, if you learned a little bit about reading music, you’re good to go.

Sorry, a little bit more than an elevator pitch, but this is first draft writing! 🙂

That is CSP in a nutshell. The CSP is a first-rate piano and it has a decent collection of non-piano voices and arranger styles. The CSP even includes the Hammond-ish “organ flutes” drawbar organ voices. So, if you want to jam out with electric guitar, you’re set. If you want to play chords with your left hand and freestyle it, the CSP is ready.

If you’re looking for a full arranger workstation, though, you’re missing some features. No pitch bend wheel, no mod wheel, no multipads, no accompaniment section (MAIN, FILL, …) buttons. No voice editing; all voices are preset.

And hey, there’s no display either! The Smart Pianist app is your gateway to the CSP feature set. You can select from a few voices and styles using the FUNCTION button and the piano keyboard, but you need the app to make full use of the CSP. Eliminating the CLP’s touch panel, lights and switches takes a lot of cost out of the product, achieving a more affordable price point.

I could see the CSP appealing to churches as well as home players given the quality of the piano and acoustic voices. Flipping the ON switch and playing piano is just what a lot of liturgical music ministers want. The more tech savvy will dig in. Pastors will appreciate the lower price of the CSP line.

From the perspective of an arranger guy, the CSP represents a shift away from the standard arranger. For decades, people want to play with their favorite pop tunes. In order to use a conventional arranger (no matter what brand), the musician must find a suitable style and the musician must have the musical skill to play a chord with the left hand, even if it’s just the root note of the chord. Often the accompaniment doesn’t really “sound like the record” and the player feels disappointed, unskilled and depressed. Shucks, I feel this way whenever I make another attempt at playing guitar and at least I can read music!

The CSP is a new paradigm that addresses these concerns. First, the (budding) musician plays with the actual recording. Next, the app generates a simplified musical score — no need to chase after sheet music. The score matches the actual audio and the app leads the player through the score in sync with the audio. Finally, the CSP’s guide lights make a game of playing the notes in the simplified score.

We’ve already seen apps from Yamaha with some of these features. Chord Tracker analyzes a song from your audio music library and generates a chord chart. Kittar breaks a song down into musical phrases that can be repeated, transposed and slowed down for practice. The Smart Pianist app includes Chord Tracker functionality and takes it to another level producing a two stave piano score.

Notice that I said “a score” not “the score.” Yamaha’s audio analysis only needs to be good enough to produce a simple left hand part and the melody. It does not need to generate the full score for a piece of music. Plus, there are likely to be legal copyright issues with the generation of a full score. (A derivative work?)

Still, this is an impressive technical feat and is the culmination of years of research in music analysis. Yamaha have invested heavily in music analysis and hold many patents. Here are a few examples:

  • U.S. Patent 9,378,719: Technique for analyzing rhythm structure of music audio data, June 28, 2016
  • Patent 9,117,432: Apparatus and method for detecting chords, August 25, 2015
  • U.S. Patent 9,053,696: Searching for a tone data set based on a degree of similarity to a rhythm pattern, June 9, 2015
  • U.S. Patent 9,006,551: Musical performance-related information output device, April 14, 2015
  • Patent 9,275,616: Associating musical score image data and logical musical score data, March 1, 2016
  • U.S. Patent 9,142,203: Music data generation based on text-format chord chart, September 22, 2015

The last patent is not music analysis per se. It may be one of several patents covering technology that we will see in the next Yamaha top of the line (TOTL) arranger workstation.

I think we will be seeing more features based on music analysis. Yamaha’s stated mission is to make products that delight customers and to provide features that are not easily copied by competitors. Yamaha have staked out a strong patent position in this area let alone climbing over the steep technological barrier posed by musical analysis of audio.

Copyright © 2017 Paul J. Drongowski

Chord Tracker revealed

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I am using the Yamaha Chord Tracker app to figure out the chords to some tunes. Chord Tracker analyzes the music in an MP3/audio file and displays a chord chart. This is great for learning new tunes and working out arrangements.

Chord Tracker can do much, much more! Yamaha really needs to produce a manual for this app to reveal all of these functions. Here are some useful tips including how to send a MIDI file for a transcribed song to your Yamaha PSR/Tyros arranger for playback.

First off, you can change the chords in the chord chart. If you don’t like a chord, just tap the chord and select a new one. Chord Tracker does a pretty decent job of identifying chords in “simple” music. For example, it did a great job with Hot Chocolate’s “Every 1’s A Winner.” (My guilty pleasure.) It didn’t do such a good job with Groovy Waters downtempo “Wicked Game.” The jazz chords (Dm/Eb, come on, man) threw Chord Tracker off. No problem, just edit the chord chart.

Here’s a crazy idea. Use a DAW to produce a three minute song with one or two chords at the beginning. Transcribe the song with Chord Tracker. When you need to create a new song from scratch, edit the new chords. Presto, a chord chart editor.

Next, you can send the chord progression to your PSR/Tyros. The Yamaha web site touts wireless connection, but you can send the song file via wired USB. I transferred the chord progression to my S950 using the Apple Camera Connection kit. (My iPad is a gen 4 running iOS9, BTW.)

The Yamaha web page for Chord Tracker states that Chord Tracker is compatible with the currently listed “Related Products.” That is true. However, Chord Tracker worked successfully with the S950 (not listed). So, even though you don’t own the latest and greatest, please give this capability a try.

On the iPad side, you need to establish a connection from Chord Tracker to your keyboard. Plug in the Camera Connection Kit and USB cable first. Then select your instrument in the Connection box on Chord Tracker’s main screen.

Choose an audio song to transcribe to a chord chart and turn Chord Tracker loose. Once you have a chord chart, tap the upload icon, i.e., that square box with an arrow shooting upward. Then tap the “Send to Instrument” button. Chord Tracker pops up a dialog in which you can enter/change the name of the song file to be created on the arranger workstation. Tap SEND and Chord Tracker sends the song file to the arranger.

Chord Tracker stores the song file in the arranger’s internal drive. It creates a directory named “ChordTracker” and stores the song file in this directory. Any other song file that you create this way is stored in the “ChordTracker” directory.

Press the SONG SELECT button on the arranger to find and select the song file. Navigate to the USER tab of the internal drive and then press the corresponding button for the “ChordTracker” directory. Then press the corresponding button for the song file itself, e.g., “every1s”, which is the name that I gave to the “Every 1’s A Winner” song file.

Press the play button. The arranger will play back the song using the currently selected style and section. Now have fun changing the style, section, tempo and so forth. You can change the style, section, etc. in real time while the song plays, making it easy to tune the song to your sonic wishes.

Of course, you can dive into SONG CREATOR and tweak away. The System Exclusive TAB reveals much of the magic behind the scenes.

Chord Tracker generates three MIDI metadata records for time signature, key signature and tempo, followed by three System Exclusive messages:

    F0 7E 7F 09 01 F7             GM reset
    F0 43 10 4C 00 00 7E 00 F7    XG system ON
    F0 43 60 7A F7                Accompaniment start

The preamble is followed by a slew of Yamaha System Exclusive messages for the chord changes:

    F0 43 7E 02 34 00 34 7F F7    Chord control (F maj/F)
    F0 43 7E 00 08 7F F7          Section control (MAIN A ON)
    F0 43 7E 02 23 00 23 7F F7    Chord control (Eb maj/Eb)

Chord Tracker does not generate the Yamaha proprietary CdS1 chunk in the MIDI file. All playback is controlled by metadata and System Exclusive messages.

We can expect to see more of these kinds of features from Yamaha. They have a US patent (number 9,142,203) for a formatted chord chart and accompaniment generator. The generator is driven by a simple, free form text chord chart.

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