Hints for live stage piano performance using Cubasis

I’ve been playing a stage piano for several years in an amateur dramatic group and have recently been looking to improve the quality of the piano sound. My main aim is to improve the piano sound in a simple but robust way, suitable for both rehearsals and live performance. I have recently tried out the new Yamaha MD BT01 midi Bluetooth adapter with an ipad and Cubasis and am getting good results. This note aims to discuss some of the practical details of getting the set-up to work, in the hope that others may find this useful. Apologies for the extended length of the document.

Before going in to detail about the set-ups, I’d like to sing the praises of forScore as a sheet music app. I’ve been using forScore with an ipad and an Airturn BT105 foot operated page turner for live performance and the system has worked flawlessly (apart from one time when I accidentally kicked the page turner away in the middle of a performance, with disastrous results… I now using masking tape to hold the page turner in place). The main drawback of the system is that the ipad is rather small to display a page of music. However, I’ve recently got an ipad pro and Apple pencil to use with forScore and this really is a dream system for piano players.

I started by reading about Ipad set-ups for live music and found a number of recent useful articles:

  1. http://music.tutsplus.com/articles/can-an-ipad-replace-my-mainstage-rig--cms-20306
  2. http://www.musicappblog.com/keyboard-ios-starter-kit/
  3. http://www.musicappblog.com/ipad-recording-studio-series/

The first article focuses on piano sounds, and the author comes out in favour of iGrand Piano as having the best and most configurable piano sounds. I looked at a number of piano sounds (including pianos in Cubasis, Garageband, Korg Module and iGrand Piano), and concluded that iGrand Piano was an easy winner. Note that my reference sound is my home piano, which is a very good 1898 C Bechstein upright. My Stage Piano is a Korg SP250, and the iGrand Piano sound is a great deal better than the SP250 main piano sound.

The second of the articles above notes “The key practical issues are MIDI connectivity, audio output and power supply for the iDevice“. I’ll address all of these points.

I started with a Steinberg UR22mk2 midi/audio interface to use with ipad and Cubasis. Running a (5-pin) midi cable from the keyboard to the interface, which connects to the ipad with a USB cable and the Apple USB-Lightning adapter works well. Cubasis handles the midi signal appropriately and sends the audio output back to the interface, which sends an audio signal to a mixer / powered amplifier (and optionally also to headphones). A minor drawback of this system is the three cables required (keyboard to interface, interface to ipad, interface to mixer/amplifier). The major drawback is that the ipad is unpowered. The UR22mk2 can be powered by USB: I used an Anker 20000mAh battery pack to provide USB power so that a mains socket wasn’t required.

I then moved on to use the Yamaha MD BT01 Midi Bluetooth adapter (the Korg SP250 has conventional 5-pin midi connectors; keyboards with USB/midi would require the Yamaha UD BT01 adapter and an additional USB power supply). Using the Bluetooth adapter:
• The keyboard sends midi input to the ipad via Bluetooth
• Ipad audio output goes via the ipad stereo mini jack (headphones) socket
• External power to the ipad is provided via the Lightning port
This is an ultra-simple system that can operate with portable power (apart from the keyboard) with only one cable required. So, how does it work in practice?

I’ve tested the hardware listed above with an ipad running Cubasis. The set up sequence is:

  1. Power up the keyboard
  2. Plug in the Bluetooth adapter
  3. Start Cubasis. In Cubasis setup, click on “Midi” and then Midi over Bluetooth: “Host”. The “Not Connected” message should change to “Connected” after a few seconds. Note that the device is then (and only then) visible in the ipad Settings / Bluetooth devices list.
  4. The external keyboard can now be used to play the internal Cubasis instruments

I have found that the set-up sequence is mostly reliable. Switching the keyboard off will cause the Bluetooth connection to the ipad to be lost, and the connection has to be manually reestablished when the keyboard is turned back on. Sometimes it is necessary to unplug / replug the MD BT01 to get the re-set-up to work. The Bluetooth connection has good range: even 30 ft from the keyboard with walls or a concrete floor in the way the connection is maintained.

One thing to note is that when the Bluetooth connection is established within Cubasis, the imported midi signal is then available to all apps on the ipad, even if they can’t connect usually. I discovered this by hearing extra sounds, and tracking it down to the midi signal being acted on in forScore. Fortunately, forScore allows the midi connection to be deactivated.

A positive side to the midi signal being available to all apps once the Cubasis Bluetooth link is running is that other apps may be controlled by the external keyboard if desired. I used iGrand Piano in this way:
• Set up Bluetooth link to Cubasis
• Have no instruments active in Cubasis (alternatively, if instruments are active set them to receive on an inactive midi channel (use the routing function in the inspector)
• Set Background Audio in Cubasis to “On” (in the Setup / Audio panel)
• Start iGrand Piano, and adjust piano sounds and settings as desired
• Play external keyboard

A disadvantage of this approach is the limited capability available in iGrand Piano. An alternative approach is to use iGrand Piano as an IAA instrument within Cubasis. The sequence is then:
• Set up Bluetooth link to Cubasis. Recommended to set Background Audio in Cubasis to “On” (in the Setup / Audio panel)
• Open the iGrand Piano app in addition to Cubasis and, in Settings, set Background Audio to on.
• Go back to Cubasis and start a new project and add a midi track.
• Add an instrument: select iGrand Piano from Inter-App instruments.
• Piano settings can be adjusted in iGrand Piano.
• Return to Cubasis and play external keyboard. Use Cubasis mixer to ensure levels are correct and no clipping occurs.

Some observations on how robust and useable these software systems are:
• The IAA system in Cubasis works well. Be aware that hitting the “Undo” button in Cubasis can undo the setting up of the IAA link (with sudden loss of sound…) and Redo won’t reestablish the link
• The notes on iGrand Piano sound for a long time: it is necessary to set the polyphony to a high setting (64 or 128) in Cubasis to avoid note drop outs.
• iGrand Piano is a CPU hog. I have run the apps on a 4th generation ipad and on an ipad pro. On ipad, a three note chord on iGrand Piano puts the Cubasis CPU meter at about 20%. Deliberate repeated fast chords with the sustain pedal down causes CPU clipping. The ipad pro is significantly better: a three note chord gives about 5% CPU use, and you really have to hammer the keyboard with sustain to cause the ipad pro to CPU clip. In either case, lifting off the sustain pedal allows the processor to cope. I haven’t tinkered with buffer sizes and latency settings to see the effects on CPU use. I suspect that the high CPU demand of iGrand Piano also means that power requirements are high (more reason to have external power for the ipad).
• Latency when using the MD BT01 is described by Yamaha as “low”. By ear, I think this a reasonable description: there may be some, but it hasn’t bothered me. However, by eye, there is clearly a lag in the images in iGrand Piano of the key being pressed, which is a little disconcerting.
• The iGrand Piano volume control may look nice but is particularly fiddly and frustrating to use, which makes it effectively unusable for live performance. The Cubasis mixer is great for volume control. [Note that, on the Korg SP250 at least, the on-board volume control adjusts audio output but not midi level]
• iGrand Piano has a transposition control which is fiddly but works. Cubasis has a transposition control, but as far as I can tell, this only works on recorded midi tracks and not on live streams. If your keyboard hasn’t got a transposition control for the midi signal, you’ll have to go out of Cubasis to adjust transposition.
• You can have both Cubasis and iGrand Piano running in the background on the ipad while another app works in the foreground. For example, I can use forScore as the foreground app to display sheet music (with the Bluetooth page turner active), and have Cubasis and iGrand Piano running in the background using midi Bluetooth to produce the desired sounds.


In summary, a midi Bluetooth adapter and ipad with a separate USB battery pack, combined with Cubasis and iGrand Piano apps, gives a relatively simple, robust, flexible and very portable way of upgrading the sound of a stage piano. I plan to test all this out in rehearsals and then in live performance.

Finally, thanks for reading this far.

p.s.
Here is my idea of a really good stage piano for use with an ipad. It would be readily portable, powered by USB, have a top class keyboard action, a connection for piano pedals (sustain and soft), a 5-pin midi out connector, an optional music / ipad rest and nothing else. All the voices and controls would be provided by connection to the ipad, linked in turn to an amplification and loudspeaker system. It would be great if an enterprising manufacturer were to produce such a device.

1 Like

Thanks for sharing your insights!

Best,
Lars