Yamaha multi-touch patents

I was on a quest for information about Virtual Resonance Modeling (VRM) when I encountered two interesting Yamaha patents. Both patents have the same obtuse title: “Musical sound information outputting apparatus, musical sound producing apparatus, method for generating musical sound information.” The U.S. Patent numbers are:

  • U.S. 11,398,210 B2, July 26, 2022
  • U.S. 11,657,791 B2, May 23, 2023

Both patents, essentially, cover the same technology — a kind of multi-touch keyboard and control scheme for synthesis. Here’s my synopsis.

Black and white keys are divided into two (or three) detection regions each as shown in the diagram below. Each region detects touch and release. Pretty simple, eh?

Yamaha U.S. Patents 11,398,210 and 11,657,791

The sound generator reacts in repsonse to touch and release differently according to key region. Here are a few examples mentioned in the patent:

  • A touch in white (black) key region Wa (Ba) initiates a tone.
  • A slide in white (black) key region Wb (Bb) applies an effect to the tone.
  • A release in Wa (Ba) stops the tone.
  • A release in Wb (Bb) stops application of the effect.

The word “effect” is meant rather broadly, including vibrato, modulation and so forth. Touch and release generate typical MIDI-like information such as note number and velocity.

Please note that a player can touch more than one key region simultaneously. The player chooses the gesture — with one or more fingers of a single hand or both hands. The sound generator could respond differently as to which region is touched first or held. Similarly, the sound generator could react differently depending upon the order (or temporal relationship) of release.

The inventors describe possibilities afforded by the invention when the sound generator is producing guitar tones. Depending upon touch gestures, the sound generator may produce a fingered tone, a plucked (picked) tone, hammer-on, fret noise or mute. Possibilities abound: one region initiates a single tone, the second region initiates a chord.

Obviously, if the idea works for two key regions, why not three or more?

The actual mechanism for key region detection depends upon the chosen key technology itself. Much of the patent describes implementation with a tablet touch screen, e.g., electrostatic sensing. They also mention a “pantograph-type elevating structure” where the player can depress independently the front and rear parts of a key.

What really caught my eye is the list of inventors: Masahiko Hasabe, Shinichi Ito, Kenichi Nishida, Masahire Kakishita, and Shinichi Ohta. These folks are heavy-hitters and have made many technical contributions to Yamaha products and its patent portfolio. Shinichi Ohta, for example, was the manager in charge of MONTAGE development!

So, make of it what you will. Yamaha has a broad and deep patent portfolio and not all of its patented tech gets into product. However, that is a rather large amount of talent interested in multi-touch, multi-zone keyboard control.

Copyright © 2023 Paul J. Drongowski

Noted in passing

A recent post about the Venova™ wind instrument reminded me about a few patent applications from last summer.

In addition to technology patents, Yamaha have been actively filing for and obtaining design patents on the physical industrial design of their products. Here are a half-dozen recently awarded design patents:

When I first saw the Venova, I thought, “Man, that looks like the physical manifestation of a virtual VL wind instrument.” Yamaha filed two patent applications for both the Venova and a close cousin: US Patent Application 2018/0254026 and 2018/0190245. If you’re interested in the gory details about the Venova design, dig in.

Ah, physics.

Copyright © 2019 Paul J. Drongowski

Genos is coming soon

Well, it’s official. Yamaha have created a special web site for Genos™ related announcements. The first posting is the teaser video which was accidentally released over the weekend. New videos will appear on September 15, 22 and 29. Dealer previews are scheduled during the last two weeks of September. Of course, we’re all dying to see the manuals and the data list PDF!

There’s one key graphic in the Yamaha annual report with the goal: Develop Products with Distinctive Individuality: Add original value to excellent basic functions and develop products others cannot imitate.

That’s a direct quote.

So, please review my summaries of recent Yamaha patents:

This is Yamaha staking out its claim in synth and arranger technology. Patents are expensive and Yamaha do not seek patent protection frivolously.

Hey, hey, serious stuff, but exciting!

Yamaha have filed several patents on styles and style playback using both MIDI data and digital audio. Not just audio drums, but pitched, melodic instrument parts.

When you hear a cello in the demo, that may very well be a recording of a real human being playing a real cello.

The playback engine tracks left hand chords. With respect to audio parts, the engine selects the most appropriate audio phrase from its library of audio recordings according to chord type. Time-stretching (etc.) adjusts for tempo and pitch-shifting adjusts for transposition. Thus, the recorded audio phrase is pitch- and tempo-matched against the musical clock and MIDI. Sounds easy, but try to do it right and do it in real-time!

I’m making a leap from patent filings to product, but my gut feeling as an engineer is strong about this one. (Feel the force, Luke.)

Or, we’ll all have a good laugh.

Copyright © 2017 Paul J. Drongowski

Yamaha CSP pianos: First take

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

New Yamaha patents

Raining like crazy today, so it’s a good chance to look for new patents and patent applications.

First, here are a few new technical patents assigned to Yamaha. US Patent 9,536,508 titled “Accompaniment data generating apparatus,” awarded on January 3, 2017, describes accompaniment generation using a combination of MIDI and audio waveforms. The accompaniment generator follows chord changes, etc. just like today’s arrangers except that it also plays back melodic (pitched) audio phrases as well as MIDI. This is very likely the nexus of the next generation of Yamaha arrangers (flagship “GENOS“).

US Patent 9,514,728 titled “Musical performance apparatus that emits musical performance tones and control tones for controlling an apparatus,” awarded December 6, 2016, describes a system for near ultrasonic communication between a tablet and a keyboard. Software on the tablet controls tone generation on the keyboard, allowing an app to play back a musical performance (e.g., MIDI over near ultra sonic sound). I suspect that some future Yamaha patent will use this technology for wireless tablet to keyboard communication in place of Bluetooth or WiFi.

The third patent, number 9,489,938 is titled “Sound synthesis method and sound synthesis apparatus” and was awarded on November 8, 2016. The patent abstract says it best:

A sound synthesis apparatus connected to a display device, includes a processor configured to: display a lyric on a screen of the display device; input a pitch based on an operation of a user, after the lyric has been displayed on the screen; and output a piece of waveform data representing a singing sound of the displayed lyric based on the inputted pitch.

Yamaha have a stellar technology base in VOCALOID. I believe they are working toward a real-time system to sing lyrics. This would be a real breakthrough especially for pitch-challenged vocalists like me!

Finally, Yamaha was awarded several design patents covering the external industrial design of synth and arranger keyboards:

    D772,974   PSR-S670   November 29, 2016
    D776,189   Montage    January 10, 2017
    D778,347   YPT-255    February 7, 2017
    D778,346   Reface YC  February 7, 2017
    D778,345   Reface CP  February 7, 2017
    D778,344   Reface DX  February 7, 2017
    D778,343   Reface CS  February 7, 2017
    D778,342   ????       February 7, 2017

The final design patent, D778,342, is perplexing. I haven’t been able to associate it with a product in the North American market. A future product perhaps? It shows a 26-key keyboard with a four way, cursor-like pad. The keyboard design is E-to-F! I/O is on the left side panel.

Tip-toe through the tech

Last year ’bout this time, we were all holding our collective breath awaiting the new Yamaha Montage. There are two products which I expect to see from Yamaha sometime in the next one to two years:

  1. The successor to the mid-range MOXF synthesizer, and
  2. The successor to the top-of-the-line (TOTL) Tyros arranger workstation.

NAMM 2017 seems a little too soon for both products. In the case of the MOXF successor, Yamaha conducted marketing interviews during the summer of 2015. I would guess that MOXF sales are still pretty good and no new products from the usual suspects (Korg, Roland) are visible on the horizon. The Krome and FA could both use an update themselves. Not much market pressure here at the moment. (Korg’s NAMM 2017 announcements are, so far, a little underwhelming.)

Read my MOX retrospective and interview follow-up.

I suspect that the Tyros successor is somewhat closer to launch. Speculation has been heated ever since Yamaha filed for a US trademark on the word mark “GENOS”. The word mark was published for opposition on November 15, 2016. “Published for opposition” means that anyone who believes that they will be damaged by registration of the mark must file for opposition within 30 days of publication. If “GENOS” is indeed the name for the Tyros successor, then the 30 day period ending December 15, 2016 is cutting it very close to NAMM 2017. Even more ludicruous if Yamaha were to begin manufacturing products printed with that name for a NAMM 2017 launch. Imagine the scrap if opposition was successful!

For quite some time, I have been meaning to summarize the key U.S. patents that I believe to be GENOS-related. (Assuming that “GENOS” is the name!) I’ve procrastinated because the launch date is most likely fall 2017 at the earliest as previous Yamaha mid- and high-end arranger models are typically launched in the fall in anticipation of the holiday selling season.

A much larger barrier is the task of reading and gisting the patents. Patents are written in legalese and are much more difficult to read than the worst written scientific papers! One of the folks on the PSR Tutorial forum suggested making a list of the top five technologies for the new TOTL arranger. I generally hate the superficial nature of “list-icles,” but the suggestion is a good one. Nothing will get done as long as the barrier is big because I would much rather jam and play! I’m supposed to be retired.

The 2016 Yamaha annual report states that Yamaha want to make innovative products which are not easily copied by competitors. Patents — legally protected intellectual property — are essential to achieving this goal. Generally, a company only applies for a patent on technology in which they have a serious business interest due to the significant cost of obtaining and maintaining patent protection.

So, here are a few of Yamaha patented technologies which could appear in future products — perhaps GENOS, perhaps others.

SWP70 tone generator

This may seems like old news…

The next generation SWP70 tone generator first appeared in the mid-range Yamaha PSR-S970 arranger workstation. The SWP70 made its second appearance in the Yamaha Montage synthesizer. The S970 incorporates only one SWP70 and does not make full use of the chip. (At least three major interfaces are left unconnected.) In keeping with Yamaha’s TOTL design practice, the Montage employs two SWP70 integrated circuits: one each for AWM2 sample-playback and FM. A second sample cache interface on the AWM2 side is unconnected.

The Tyros successor likely will use two SWP70 tone generators, too. The number of available tone generation channels with two SWP70s will be massive (512 channels). Yamaha could opt for a single SWP70 and still outmatch the current generation Tyros 5. Like the Montage, there will be enough insert effect DSP processors to cover each style and user part, as many as two for every part.

It will be interesting to see (and hear) if the GENOS will make use of the second sample cache interface. A second cache would not only support more tone generation channels, but might be necessary for long, multi-measure musical phrases that are needed for full audio styles (discussed below).

The SWP70 flash memory interface follows the Open NAND FLASH interface (ONFI) standard, the same as solid state drives (SSD). ONFI memory devices can be stacked on a bi-directional tri-state bus, so potentially, the GENOS could support a large amount of internal waveform storage. This flash memory will contain the “expansion memory,” that is, physical memory reserved in flash memory for user waveforms. The expansion flash memory expansion modules (FL512M, FL1024M) are dead, Jim.

If you’re interested in Yamaha AWM2 tone generation, here’s a few patents to get you started:

  • Patent 9,040,800 Musical tone signal generating apparatus, May 26, 2015
  • Patent 8,383,924 Musical tone signal generating apparatus, February 26, 2013
  • Patent 8,389,844 Tone generation apparatus, March 5, 2013
  • Patent 8,957,295 Sound generation apparatus, February 17, 2015
  • Patent 8,035,021 Tone generation apparatus, October 2011
  • Patent 7,692,087 Compressed data structure and apparatus and method related thereto, April 6, 2010

U.S. Patent 8,957,295 is the patent issued for the SWP70 memory interface. U.S. Patent 9,040,800 describes a tone generator with 256 channels — very likely the SWP70.

Pure Analog Circuit

This may seem like old news, too, since Pure Analog Circuit (PAC) debuted in the Yamaha Montage.

Pure Analog Circuit is probably the least understood and least appreciated feature of the Montage. It’s not just better DACs, people. The high speed digital world is very noisy as far as analog audio is concerned. Yamaha separated the analog and digital worlds by putting the DACs and analog electronics on their own printed circuit board away from noisy digital circuits. Yamaha then applied old school engineering to the post-DAC analog circuitry, paying careful attention to old school concerns like board layout for noise minimization and clean power with separate voltage regulation for analog audio. Yamaha’s mid- to high-end products have always been quiet — PAC is pristine.

Since the PAC board is a separate, reusable entity, I could see Yamaha adopting the same board for GENOS.

Styles combining audio and MIDI

Yamaha are constantly in search of greater sonic realism. Existing technologies like Megavoices and Super Articulation 2 (Advanced Element Modeling) reproduce certain musical articulations. However, nothing can really match the real thing, that is, a live instrument played by an experienced professional musician. PG Music Band-in-a-Box (BIAB), for example, uses audio tracks recorded by studio musicians to produce realistic sounding backing tracks. The Digitech TRIO pedal draws on the PG Music technology for its tracks. (“Hello” to the Vancouver BC music technology syndicate.)

Yamaha have applied for and been granted several patents on generating accompaniment using synchronized audio and MIDI tracks. Here is a short list of U.S. patents:

  • Patent 9,147,388 Automatic performance technique using audio waveform data, September 29, 2015
  • Patent 9,040,802 Accompaniment data generating apparatus, May 26, 2015
  • Patent 8,791,350 Accompaniment data generating apparatus, July 29, 2014
  • Application 13/982,476 Accompaniment data generating apparatus, March 12, 2012

There are additional patents and applications. Each patent covers a different aspect of the same basic approach, making different claims (not unusal in patent-land). Yamaha have clearly invested in this area and are staking a claim.

The patents cite four main motivations, quoting:

  1. The ability to produce “actual musical instrument performance, human voices, natural sounds”
  2. To play “automatic accompaniment in which musical tones of an ethnic musical instrument or a musical instrument using a peculiar scale”
  3. To exhibit the “realism of human live performance”
  4. To advance beyond known techniques that “provide automatic performance only of accompaniment phrases of monophony”

Your average guy or gal might say, “Give me something that sounds as natural as Band-in-a-Box.” Yamaha sell into all major world markets, so the ability to play ethnic instruments with proper articulation is an important capability. Human voice, to this point, is limited to looped and one-shot syllables, e.g., jazz scat. The new approach would allow long phrases with natural intonation. [Click on images in this article for higher resolution.]

audio_accompaniment_tracks

Currently, mid- and high-end Yamaha arrangers have “audio styles” where only the rhythm track is audio. The patents cover accompaniment using melodic instruments in addition to rhythm instruments. The melodic audio tracks follow chord and tempo changes just like the current MIDI-based styles. Much of the technical complexity is due to synchronization between audio and MIDI events. Synchronization is troublesome when the audio tracks contain a live performance with rubato. Without good synchronization, the resulting accompaniment doesn’t feel right and sounds sloppy.

Accompaniment from chord chart

This next feature will be very handy. U.S. Patent 9,142,203 is titled “Music data generation based on text-format chord chart,” September 22, 2015. If you use textual chord charts (lyrics plus embedded chord symbols), you will want this!

chord_chart_example

Simply put, the technique described in this patent translates a textual chord chord to an accompaniment. The accompaniment is played back by the arranger. The user can select tempo, style, sections (MAIN, FILL IN) and so forth.

The translator/generator could be embedded in an arranger or it could be implemented by a PC- or tablet-based application. Stay tuned!

Selectively delayed registration changes

A registration is a group of performance parameters such as the right hand voice settings, left hand voice settings, accompaniment settings, and so forth. Mid- and high-end arrangers have eight front panel buttons where each button establishes a set of parameter values (“readout”) when the button is pushed. It’s the player’s job to hit the appropriate button at the appropriate time during a live performance to make voice settings, etc. A player may need a large number of buttons, if a musical performance is complicated.

Usually only a few parameters are different from one registration to the next. Recognizing this, the technique described by U.S. Patent 9,111,514 (“Delayed registration data readout in electronic music apparatus,” August 18, 2015) delays one or more parameter changes when a button is pushed. The user specifies the parameters to be delayed and the delay (such as the passage of some number of beats or measures, etc.) Thus, a single registration can cover the work of multiple individual registrations.

delayed_registration

I’ll have to wait to see the final product to assess the usefulness of this feature. Personally, I’d be happy with a configuration bit to keep OTS buttons from automatically turning on the accompaniment (ACCOMP). Sure would make it easier to use the OTS buttons for voice changes.

Ensembles / divisi

Tyros 5 ensemble voices assign played notes to individual instrument voices in real time, allowing a musician to perform divisi (divided) parts. Tyros 5 ensembles can be tweaked using its “Ensemble Voice Key Assign Type List.” Types include open, closed, and incremental voice assignment. U.S. Patent 9,384,717, titled “Tone generation assigning apparatus and method” and published July 5, 2016, extends Tyros 5 ensemble voice assignment.

The technique described in 9,384,717 gives the musician more control over part assignment through rules: target depressed key, priority rule, number of tones to generated, note range, etc. The rules handle common cases like splitting a single note to two or more voices.

ensemble_rules

These extensions could lead to some serious fun! I didn’t feel like the Tyros 5 ensemble feature was sufficiently smart and placed too many demands on the average player, i.e., less-than-talented me. The rules offer the opportunity to shift the mental finger work to software and perhaps could lead to more intuitive ensemble play. Neat.

Voice synthesis

As I alluded to earlier, arrangers make relatively primitive use of the human voice. Waveforms are usually limited to sustained (looped) or short (one-shot) syllables.

Yamaha have invested a substantial amount of money into the VOCALOID technology. VOCALOID draws on a singer database of syllable waveforms and performs some very heavy computation to “stitch” the individual waveforms together. The stitching is like a higher quality, non-real time version of Articulated Element Modeling (AEM).

VOCALOID was developed through a joint research project (led by Kenmochi Hideki) between Yamaha and the Music Technology Group (MTG) of the Universitat Pompeu Fabra in Barcelona, Spain. VOCALOID grew from early work by J. Bonada and X. Serra. (See “Synthesis of the Singing Voice by Performance Sampling and Spectral Models.”) More recent research has stretched synthesis from the human voice to musical instruments. Yamaha hold many, many patents on the VOCALOID technology.

Patent 9,355,634, titled “Voice synthesis device, voice synthesis method,” is a recent patent concerning voice synthesis (May 31, 2016). It, too, draws from a database of prerecorded syllables. The human interface is based on the notion of a “retake,” such as a producer might ask a singer to make in a recording studio using directives like “put more emphasis on the first syllable.” The retake concept eliminates a lot of the “wonky-ness” of the VOCALOID human interface. (If you’ve tried VOCALOID, you know what I mean!) The synthesis system sings lyrics based on directions from you — the producer.

An interface like this would make voice synthesis easier to use, possibly by novices or non-technically oriented musicians. The big question in my mind is whether voice synthesis and editing can be sped up and made real time. Still, wouldn’t it be cool if you could teach your arranger workstation to sing?

Music minus one

This work was conducted jointly with the MTG at the Universitat Pompeu Fabra. A few of the investigators were also involved in VOCALOID. Quoting, “The goal of the project was to develop practical methods to produce minus-one mixes of commercially available western popular music signals. Minus-one mixes are versions of music signals where all instruments except the targeted one are present.”

This is not good old center cancellation. The goal is to remove any individual instrument from a mix regardless of placement in the stereo field. You can hear a demo at http://d-kitamura.sakura.ne.jp/en/demo_deformation_en.htm.

I doubt if this technique will appear on an arranger; the computational requirements are too high and the method is not real time. However, “music minus-one” is very appealing to your average player (that is, me). My practice regimen includes playing with backing tracks. I would love to be able to play with any commercial tune on whim.

There are patents:

  • US Patent 9,002,035 Graphical audio signal control
  • US Patent 9,224,406 Technique for estimating particular audio component
  • US Patent 9,070,370 Technique for suppressing particular audio component

and there are scientific papers:

  • “Audio Source Separation for Music in Low-latency and High-latency Scenarios”, Ricard Marxer Pinon, Doctoral dissertation, Universitat Pompeu Fabra, Barcelona, 2013.
  • D. Kitamura, et al., “Music signal separation by supervised nonnegative
    matrix factorization with basis deformation,” Proc. DSP 2013, T3P(C)-1, 2013.
  • D. Kitamura, et al., “Robust Music Signal Separation Based on Supervised Nonnegative Matrix Factorization with Prevention of Basis Sharing”, ISSPIT, December 2013.

Music analysis

Yamaha have put considerable resources into what I would call “music analysis.” These technologies may not (probably will not) make it into an arranger keyboard. They are better suited for PC- or tablet-based applications.

I think we have seen the fruits of some of this labor in the Yamaha Chord Tracker iPad/iPhone application. Chord Tracker identifies tempo, beats, musical sections and chords within an audio song from your music library. It displays the extracted info in a simple chord chart and can even send the extracted “lead sheet” to your arranger. The arranger plays back the “lead sheet” as an accompaniment using the selected style.

We’re probably both wondering if Chord Tracker will integrate with the chord chart tool described above. Stay tuned.

Yamaha Patent 9,378,719 (June 28, 2016) is a “Technique for analyzing rhythm structure of music audio data.” Patent 9,117,432 (August 25, 2015) is an “Apparatus and method for detecting chords.” I wouldn’t be surprised if Chord Tracker draws from these two patents.

Yamaha has also investigated similarity measures and synchronized score display:

  • Patent 9,053,696 Searching for a tone data set based on a degree of similarity to a rhythm pattern, June 9, 2015
  • 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

I’m not sure where Yamaha is going with similarity measures and searching. Will they use similarity measures to selected accompaniment phrases? Who knows?

The work on score display synchronizes the display of the appropriate part of a musical score with its live or recorded performance. These techniques may be more appropriate to musical education and training, particularly for traditional brass, string and woodwind players. Yamaha derives considerable revenue from traditional instruments and this is perhaps a way to enhance their “ecosystem” for traditional acoustic instruments.

Score display is one possible application of Yamaha’s patented technique to transmit performance data via near-ultrasonic sound. The technique borrows one or more tone generation channels to generate the near-ultrasonic data signal. See my earlier post about U.S. Patent 8,779,267 for more details.

So long for now!

That’s it! I hope you enjoyed this brief tour through a few of Yamaha’s recent patent grants and filings.

If you want more information about a particular patent, then cruise on over the the U.S. Patent and Trademark Office (USPTO) web site. Navigate to patent search and plug in the patent number.

Copyright © 2017 Paul J. Drongowski

Serial memory and tone generation

Ah, September. Soon it will be time to speculate about new products at the Winter 2016 NAMM!

Every now and again, I take a pass through recent patent filings from Yamaha to get an idea about future product developments. Of course, the tech in a filing may never make it to product. However, a few common threads begin to appear over time.

This post starts with a patent application having the inauspicious title, “Sound Generation Apparatus.” This US application 2014/0123835 was filed on November 5, 2013 and is based on Japanese patent -244002, which was filed November 5, 2012.

First, a little background about the Yamaha tone generation architecture. Yamaha has used the same overall architecture for mid- and high-end workstations and tone modules since the mid-1990s. (TG-500, anyone?) These products employ one or more large scale integrated circuits for tone generation. Current versions of the tone generator IC, the SWP51L, has two dedicated memory channels for waveform data. Each channel has a 16-bit parallel data bus and a parallel address bus (24 or more bits wide). The parallel interface takes at least 40 pins per channel.

That’s a lot of incoming and outgoing connections (80 plus pins for both channels). IC packaging costs are in the range of $2.50 USD to $4.50 per pin. So, there is a direct relationship between the number of IC pins and manufacturing cost. Ultimately, this cost has a real effect on profit and the final price of the product.

The Yamaha patent application describes a serial interface for waveform memory in place of a parallel interface. The serial interface requires six pins per channel. Instead of 80 pins, the serial interface approach uses only 12, providing an 8 to 1 savings in packaging costs alone.

The application cites the Winbond 25Q series as the kind of flash memory to be supported by the serial interface. The largest 25Q device has a 64MByte capacity and can sustain a 40MByte/second transfer rate (quad SPI mode). This is nearly sufficient bandwidth to drive 128 44,100Hz stereo polyphonic voices (about 45MBytes/sec).

If you do the math that’s 128 times 44,100Hz times eight bytes. Two successive samples are required in order to perform interpolation although the oldest sample could be cached.

The product implications are interesting. At the low end of the scale (one or two channels), the device footprint is much smaller. The small size allows a corresponding decrease in the size of the product. Maybe a guitar pedal stomp box?

The high end of the scale is more intriguing. It becomes possible to build a tone generator IC with four or even eight independent channels of tone generation where each channel is driven by its own memory stream. We’re talking 1,024 polyphonic voices in the same LSI footprint as today’s SWP51L.

There are design implications for entry-level keyboard products, too. The SWL01 system on a chip (SOC) integrates both CPU and tone generator onto the same IC. Waveform data (samples) travel on the same bus as CPU instructions and data. A serial SPI interface requires only six pins and might let designers shift waveform storage from ROM on the system bus to a dedicated memory bus and channel. Software might be able to perform new tasks such as variation effects with more bandwidth available to the CPU on the system bus.

I feel confident to predict that the next generation of Standard Wave Processor (SWP) is in development. The SWP51L has been around for a while (including Tyros5). Here are a few key products and members of the SWP50 family:

    Product   Year  TG chip
    --------  ----  -------
    Tyros     2002  SWP50
    Motif XS  2007  SWP51
    Tyros 3   2008  SWP51B
    Tyros 5   2013  SWP51L

It is definitely time for a new design, not an incremental refresh.

Yamaha sees its internal integrated circuit capability as a strategic advantage. Up to this point, Yamaha have both designed and fabricated its own ICs. Last year, Yamaha transferred its fabrication line to Phenitec Semiconductor. Yep, Yamaha has gone fabless. This gets a huge capital expense off its balance sheet. It also means that Yamaha is under less pressure to reuse the same parts across product lines in order to get its IC manufacturing volume up. This is one reason why the SWP51 has had such long legs and why the SWL01 is used across all of the E-series arrangers. Volume, volume, volume! The pressure to (re)use Yamaha’s own IC solutions has been reduced.

We’ll see if Johnny can read (defenses) against Dick LeBeau. Go Browns!