Irrgärten
for two pianos and live-electronics
studio : Harvard University and EMPAC/ 2010 /
duration: 24 min
dedicated to Jacopo Baboni Schilingi
first performance by Jennifer Hymer and Bernhard Fograscher on January 21, 2011, Klub Katarakt Festival - Hamburg
The composition is about memory and could be compared to a walk through different mazes (Irrgärten).
Both pianos constantly play very similar material and build up very energetic dialogues and at times a common voice.
The piece is structured in sections of contrast. Little by little, excerpts of later sections are appearing like foreshadows. While the composition progresses, certain sections of earlier material are partially or entirely repeated - though, the electronics are different for those repeated piano parts.
While walking through the maze one tries to get a picture of the path: certain places look similar, but they are different in reality - one gets trapped.
The electronics are realized with two iPhones or two iPods (4th generation), one for each pianist.
The built-in microphone is used to detect piano notes and to synchronize the electronic sounds to the live part.
recordings
simulation with Yamaha Concert Disklavier
piano parts withouth electronics
electronics
This composition is my first attempt to experiment with “easy electronics”.
I’m using the capacity of the iPhone to play back prepared sounds. The build-in microphone is used to track the instruments amplitudes and synchronize sound files to the interpretation of the pianists. The electronics are conceived in such a way that each player has an iPhone on the music stand and can control them without the help of a technician or assistant.
One problem with the realization of pieces involving instruments and electronics is the lack of proper rehearsal conditions. Very often the instrumentalists will rehearse their parts like chamber music without getting used to the sound world, nor the interaction with the electronics. At a very late moment, often just a couple of days before the concert, the electronics are added and the musicians have simply no time to adapt their interpretation to this new situation.
My desire to avoid returning to a pre-produced CD track, which causes many problems in terms of synchronization with the instrumental part and forces the musicians into a rigid timeframe, was the impetus to experiment with the capacity of the iPhone. The electronic sounds are short sequences, which are re-synchronized to the live part using amplitude tracking with the build-in microphone.
This set up is, indeed, very limited compared to live-processing with Max/MSP or other computer software. However, I wanted to see how far I could go, musically, with such a sparse configuration that avoids microphones, sound cards, and computers all together.
There is no need for loudspeakers in the concert hall. The electronics are played back through four small, high quality monitors, two of which are placed inside each piano. The monitors face the piano lid, which acts as a sound reflector, and they are placed as far apart as possible from each other. For example, one monitor is close to the keyboard, and the other one is close to the low strings. The electronic sounds should fuse as much as possible with the instrumental sounds. The mini-jack output of each iPhone is connected to the monitors inside the piano. The sound files from each iPhone are in stereo.
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The mini-jack output of each iPhone is connected to the monitors inside the piano with a cable TRS 1/8 inch - TRS 1/4 inch. The soundfiles for each piano are stereo.
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I hope the setup more easily enables musicians to rehearse with the electronics and allows them to prepare the installation for a performance without a sound technician.
the iPhone interface
There are two separate applications - one for each piano (Irrgaerten-1 and Irrgaerten-2), downloadable from the iTunes AppStore.The interface looks the same on both applications, but the electronic scores (the Events) and the sound files are different.
To start a rehearsal, on presses the “settings” button on the main interface.
The "loudspeaker test" is used to ensure that the two channels are connected to the corresponding monitor inside the piano.
The "chromatic scale" plays back a chromatic scale from the lowest to the highest piano note and serves to set the general level on the monitors (7 on the rotary knob for the Fostex Monitors is a good reference). The output volume of the iPhone should be set to maximum. This sound file can also be used to determine the sound quality of the loudspeakers in cases where the Fostex monitors are not available. The sound should be as natural as possible and evoke the impression that the real piano is playing. The use of small computer or game loudspeakers is not recommended, as they are unable to reproduce the sound quality of a piano.
The “Adjust tuning” feature will play a repeated A4 note at 440Hz. The iPhone tuning can be adjusted to the tuning of the piano with the slider below the switch. The new tuning value is stored in the preferences of the application and is ready to be used. There is, thus, no need to go back to the tuning procedure between rehearsal and concert. OpenAL, the lowest level of sound playback within the iPhone API, allows the tuning feature to be accessed.
Because the various iPhone/iPod models have different built-in microphones, the input signal varies from model to model. The overall sensitivity is too high, which results in false triggers when the respective other piano is playing loud notes. By covering the built-in microphones with sticky tape and taping the iPhones to the piano music stand, they act like contact microphones. That way each iPhone is only picking up the notes from the own instrument. The sensitivity value of 0.99 (less sensitive) worked best for the iPod (4th generation) but this value may vary depending on the used piano. To adjust the threshold, on uses the function "adjust microphone trigger threshold." Each note played on the piano with the dynamic, forte, should gate two consecutive chords in the electronics part. However, the second chord in the electronics part should not "auto-trigger" another sound file. If that happens, the microphone is set too sensitively. The sensitivity value is stored in the preferences of the application and used from then on.
Press “done” to return to the main screen.
"update events from the internet":
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The electronic score is stored as a database on the device independent of the sound files. Each Event is marked in the musical score with a number. The numbers are different for each piano because the sound files are not always triggered at the same time. Each Event contains the information as to which sound file to play, as well as data about volume and durations. If an update (corrections) to these electronic scores becomes necessary, I shall upload a new database onto a specific html page. |
The button “update events from the internet” can be used to download the updated version. The location of this updated file is known to the application, thus no further information is necessary. Just press the button and wait for the confirmation message.
For the update to work you need obviously a connection to the internet - through the phone provider or WIFI.
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The large rectangular area on the top of the screen is the progress bar. It gives a visual feedback, for example, how far along one is within any given Event. |
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After an Event has begun, the progress bar scrolls from left to right. When the progress bar reaches the right edge, the Event is finished. |
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Most often, the display then presents a “green” progress bar. This indicates that the iPhone has activated the internal microphone and is waiting (listening) for the next note to be played. The pianist sees the indication, “green,” for such moments in the instrumental score. When the pianist articulates the next note, the iPhone automatically starts the next Event, and thus plays synchronously with the piano. This gives musicians some freedom for rubati and interpretation. Nonetheless, the metronome indications in the score should be as accurate as possible. |
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Additionally, there are several places where the pianist is required to touch the button, “touch,” on the lower left corner of the interface to switch the listening feature back on (marked with the term, “touch,” in the score). |
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If the following Event requires this manual “touch” action, the progress bar of the current Event is “red” to remind the player of the upcoming "touch" action. |
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Once the previous Event has terminated and the iPhone is ready for the touch action the progress bar turns “pink.” |
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To navigate to a different Event during the rehearsal process, the pianist must press the “prepare” button, scroll to the desired Event number, and select it from the menu. The application returns automatically to the main screen, and the small number on the right side of the “prepare” button indicates the prepared Event number. |
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Certain Events (for example: piano 1 - Event 49) do not simply play one single sound file. For the entire duration of the Event, the microphone conveys loud notes in the piano part and triggers short buffered sound files which were preloaded at application start. In these sections, the rendering of the electronics may vary from performance to performance, depending on the interpretation. The progress bar is “blue” for these Events. |
technical requirements
• Two iPhone devices (possible models iPhone 3GS, iPhone 4, iPod touch 4th generation)• Four small, high quality active monitors, two inside each piano, placed on a pieces of foam
• Two cables to connect the output of the iPhones to the monitors
• Electricity on both pianos for the powered monitors
alternative loudspeakers
Instead of the Fostex speakers, other small high quality nearfield monitors can be used.Using small computer or gaming speakers is not recommended as they are unable to reproduce the sound quality of a piano. The playback of the soundfiles should evoke as much as possible the illusion that the sounds are produced by the piano itself.
Genelec 1029A
disposition of the pianos on stage
In order for the piano lids to reflect the electronic sounds into the concert hall, they must be opened to their maximum height and face the audience.
The following arrangement allows for this and it enables the pianists to communicate visually with each other.
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explanations and symbols in the score
All accents should be played clearly louder than the dynamics of the sourrounding notes. All alterations are valid for the entire measure. Repetitions of alterations are only printed as reading aids.
Many sections of the piano part are notated on a “double” system. The treble clef is extended upwards and reads 2 octaves above the normal treble clef, the bass clef is extended downwards two octaves. This makes fast switches between registers easier to read.
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In sertain sections silent chords are put into the middle pedal and used as resonances. |
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The same symbol in parenthesis is a reminder that there is still a chord in the middle pedal. |
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Release the middle pedal. |
downloads
download application Irrgaerten-1 (electronics for piano part 1) from the iTunes AppStore 
download application Irrgaerten-2 (electronics for piano part 2) from the iTunes AppStore optional remote control with a Macintosh computer
A third musician can optionally oversee the progress on both iPhones and if needed perform actions remotely.
A Max/MSP stand-alone application can communicate over the Airport TCP Network (using OpenSoundControl) with both iPhones.
The interface provides feedback over the actual state of both iPhones and allows to perform any action which could be
also accessed directly on the iPhone devices. In the event that a pianist misses to press a button, the third musician could
intervene and correct it during rehearsals or performances.
Setting up the connection between the iPhones and the Max/MSP application
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Under the Airport menu in the menu bar create a new network. |
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name the network osc and give it a five-digit password for example 12345 |
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in the Network preferences create a new location "osc-wifi" and click on the Advanced button on the lower right |
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under the TCP/IP rider configure the network with the manual address 192.168.0.188
It HAS TO BE this address, otherwise the connection will not work |
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under the Apple menu/Location make sure the "osc-wifi" configuration has been activated |
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start the Max/MSP applicaton |
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on the iPhone make sure, Bluetooth is disabled (unter Settings / General) |
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under Settings connect to the WI-FI network "osc" |
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enter the password 12345 |
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pressing the blue arrow on the right of the osc network brings up the details of the connection. It takes sometimes a moment, but eventually you should see an IP Address provided by the osc Network. |
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after starting the application, press the settings button |
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on the multi switch remote control, press Max |
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if all the settings were correctly performed, the iPhone interface confirms the connection and shows it's own IP address |
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this IP address appears also in the Max window |
| repeat the same steps on the second iPhone | |
