This is a new way of playing the piano as a left-hander: A mirrored keyboard for left-handers with simultaneous mirroring of the velocity and thus the key volume - the high left notes for the melody sound stronger than the low right notes in the bass, as is the case with conventional right-handed pianos in a reversed right-left arrangement.
This is made possible by the BomeBox and a KeyboardMirror MIDI Translator program, which not only mirrors the notes but also mirrors the key volume to the inverted left-handed playing. The program was developed by us and is published here on the website.
With the BomeBox and our program, a MIDI-capable electric piano or keyboard can be turned into a left-handed instrument.
Developement
Since some years I play occationally on the with the BomeBox inverted keys of my electric piano. I noticed that the left-hand high melody notes always sounded too soft in my and the right-hand bass notes too loud. I intuitively tried to compensate for this by pressing the left-hand keys harder and pulling back the right hand in the bass, which led to a physical imbalance, but not to a really satisfactory sound result. Particularly with chords, the high notes were simply swallowed up and drowned out by the excessively loud low notes.
After playing with Heidi Schneider on a mechanical left-handed Blüthner piano, where the high melody suddenly became effortlessly audible, I looked into the cause. On upright pianos and electric pianos, the right-hand keys are set louder for the melody and the left-hand keys softer for the bass. Eighther increasing continuously across the entire keyboard or in blocks. If we simply mirror such instruments, this ratio remains and is amplified or attenuated completely the wrong way round for the left-handed keyboard.
We then experimented with the “velocity” (key weighting) factor and worked out various settings, one of which suits my electric piano best. For me, the result makes a big difference compared to mere mirroring and is so overwhelmingly good that I was able to develop a real joy of playing inverted. We would like to share this improvement and enable other lefthanded players to benefit from it too. The electric pianos from different companies are balanced differently. We have therefore pre-programmed different gradations of volume distribution.
Requirements
You need a MIDI-capable electric piano or keyboard. It should either have MIDI jack input and output or a MIDI USB-to-host connection.
To ensure that the electric piano only outputs the mirrored sound and not the original sound, the MIDI option local-control off must be activated. This is easily done via a conected computer keyboard or number pad. Alternatively, the MIDI mode “local-control off” can also be set on the respective instrument. This is usually done using a key combination that is found in the manual and is different for every electric piano, or on keyboards via the display.
It should also be noted that through the factor velocity the volume ratio of the notes is also mirrored, but not the mechanical key weighting built into higher-quality instruments, where the right-hand keys are easier to press and the left-hand keys have more resistance. These are generally unsuitable for mirroring, as the high keys are then too heavy and the low keys too light to press.
If your electric piano or keyboard meets these requirements, you can purchase the BomeBox from Musikhaus Thomann and get the program played on it. You can do this by telephone or e-mail before ordering, or by indicating in the free text field when ordering that you would like to have the program on it. If you already have a BomeBox, you can load the program onto it yourself.
Required Devices
- Electric piano or keyboard with MIDI jack input and output or MIDI USB-to-host. It must support local-control off. The instrument should not have a strong mechanical key weighting, as is often the case with expensive electric pianos, as this cannot be mirrored.
- The BomeBox, e.g. from Thomann, either with oder without a flange, depending on whether the box is to be screwed on or not.
- A power supply for the BomeBox, e.g. via a5 Volt Micro-USB cell phone charger, via Power-over-Ethernet or via a USB hub with integrated power supply.
- A USB hub for connecting the USB-to-host cable and/or the number pad. We use this this USB splitter cable with integrated USB hub. However, you can also use a USB hub with power supply and use it to supply the BomeBox with power, see FAQs.
- For the connection to the electric piano:
- Either a USB cable with suitable plugs, usually USB type A on the side of the BomeBox and type B on the side of the instrument, e.g. this one or this one here. This must be connected via a USB hub, otherwise the connection to the piano will be interrupted!
- Or two 5-PIN DIN MIDI cables, e.g. this set or two of these here.
- To control the program, a number pad (recommended) with USB cable or USB dongle or a QUERTY/QUERTZ keyboard. We use this number pad with USB dongle, which is also available wired as an alternative. Both must be connected via the USB hub.
Installing the Program
To use the KeyboardMirror program, it must be installed and activated on the BomeBox as a MIDI translator.
At Musikhaus Thomann, the program can be installed on the BomeBox (219€) free of charge on request.
Alternatively, you can install it yourself: Keyboard Mirror Installation
Usage
You connect the BomeBox to your electric piano or keyboard with two MIDI jack cables so that the output of the piano is connected to the input of the BomeBox and the output of the BomeBox is connected to the input of the piano. Alternatively, you can connect a USB hub to the BomeBox and a USB cable that fits into the USB-to-host output of the electric piano. You connect a normal computer keyboard or a number pad (numeric keypad) to the BomeBox via the USB hub. The BomeBox must be connected to the power supply and takes a few seconds to start up. After starting, the activated KeyboardMirror program is started and the default setting is loaded. If two tones sound simultaneously, any number can be pressed and local-control off is sent to the instrument. The mirrored instrument is now ready for use.
Alternatively, you can toggle between MIDI-on and MIDI-off using the comma key , on the number pad.
Press Enter to preset the optimum key volume gradient of 100-125% for my electric piano.
You can use the numbers 1-9 to vary these and adapt them to your electric piano/keyboard. These can be increased in 5% increments up to 140%.
0: Right-handed keyboard without changing the weighting.1: Left-handed keyboard without changing the weighting.2: Left-handed keyboard with weighting 100-105%, a very slight change in weighting.3: Weighting 100-110%4: Weighting 100-115%5: Weighting 100-120%6: Weighting 100-125%, default setting7: Weighting 100-130%8: Weighting 100-135%9: Weighting 100-140%, a very strong change in weighting.
The point of invertation of the keyboard is preset to the middle note D, also reached by the plus sign +. A few notes are missing in the high range and some are added in the low range compared to the right-handed keyboard. The minus sign - can be used to switch to G sharp, where notes are added in the high range and missing in the low range.
The division sign / on the number pad or the s (split) key splits the keyboard in the middle. The left half of the keyboard is for left-handers, the right half for right-handers. The idea for this was provided by Dipl. med. Heidi Schneider. This can be used for your own mirrored synchronized playing in the relearning process as well as for teaching. The division is canceled with the * sign on the number pad or the n key (normal).
The KeyboardMirror can be deactivated with Esc or Del, or the backspace key. Mirroring is switched off and local-control is switched on.
Press the comma key , on the number pad or the l key to switch local-control on/off.
Restrictions
- The MIDI sound of the electric piano may sound slightly different from the normal sound without MIDI use.
- The weighting of the keys varies depending on the instrument manufacturer and this may not match the programmed opposite weighting.
- As already mentioned, a mechanical key weighting, e.g. of weighted hammers or keys, cannot be mirrored.
License and disclaimer
MIT License
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