Zell ET / MT
App Version: 1.3 / 1.2
About the Apps
Zell ET ("Equal Temperament") and Zell MT ("Meantone Temperament") are two iOS applications which allow you to play the sample sets of the Christian Zell harpsichord of the Museu de la Música de Barcelona on a MIDI keyboard connected to your iOS device. Both apps are based on the Napo framework. Please read the Napo documentation and in particular the Napo user manual to learn about its features and limitations.
Furthermore, there is an app bundle with Zell ET and Zell MT for the same price as a single app. So if you purchase one of the apps, you can later by "bundle completion" download the other one for free. If you would like to use only one of the apps, you need to download only that one and thus can save storage space on the device.
|Zell ET||Zell MT||Zell ET + Zell MT|
Originally, Napo is tailored for organ instruments. Therefore the following remarks:
- For a percussive instrument like a harpsichord or piano, a small latency (the time interval between pressing a key and the creation of sound) is more important than with an organ (where there pipes are in some distance to the console, anyway). Hence, for Zell ET/MT, 11.6 instead of 23.2 milliseconds are the default setting of the buffer duration.
- Furthermore, a harpsichord is rather not placed in a church or cathedral but in a smaller room with less reverb. Too much reverb would cover the key sounds that are included in the sample file and contribute quite much to an authentic sound and playing feel. That is why the parameters for the settings Short, Medium and Long of the iOS reverb are different from those of our organ apps.
- As already stated, the key release noise is an essential part of the sound. Thus it is rendered always, even for the reverb settings iOS and Convolution. They are in the release part of the sample files, which is cut off in case of organs when using artificial reverb, to remove the room-dependent part / the recorded reverb tail.
- The switch "8' Laute" is not an independent stop but a so-called "lute stop", a damper mechanism for the stop 8' I. This means: If "8' I" is off, then "8' Laute" has no effect. If "8' I" is on, then turning on "8' Laute" leads to a change of the sound but not to additional tones.
- Another difference to an organ instrument: If an additional harpsichord stop is pulled while keys are pressed, then this does not have the immediate effect of additional tones, because the keys are already down and the added strings are not plucked then. Only when you press the keys again, the additional strings will sound.
- Some texts in the Zell apps (e.g. "windchest") do not make sense for a harpsichord. Please ignore these cosmetical flaws. They shall be corrected in a future version.
- Because there are only a few stops, the Napo combination system is unnecessary for a harpsichord. In the interest of a uniform user interface we have still kept it for Zell ET/MT. Anyone who is familiar with one of our organ apps will immediately feel at home with Zell ET/MT.
It should be noted that Zell ET is retuned to 440 Hz while Zell MT is based on 415 Hz like the original instrument. This can be changed with the pitch setting of the apps.
As Zell ET and Zell MT have the same user interface, for easier discrimination of both apps the letters "ET" or "MT" are displayed at the left bottom:
In the versions 1.1 of the apps we have spread the stops to two manuals and added a coupler. Even though the real instrument has only one manual, and elsewhere we are rather reluctant to add elements that are not present at the original, we did not want to forgo this simple means to increase the musical versatility.
As it is common for harpsichord with two manuals, the lower manual now carries 8', 4' and lute stop, the upper manual the other 8'. The lower manual can be coupled to the upper manual. The stops knobs at the screen are arranged according to their affiliation to the manuals.
Starting with version 1.3, the note range of Zell ET is extended from C - d3 to FF - f3. The needed sound data was created from existing sound material by using "simple pitch shifting" of the Wavosaur program. The concerned MIDI note numbers:
|36 C||29 F|
|37 C#||30 F#|
|38 D||31 G|
|39 D#||32 G#|
|40 E||33 A|
|41 F||34 A#|
|42 F#||35 B|
|84 C||87 D#|
|85 C#||88 E|
|86 D||89 F|
About the Sample Sets
The sample sets which underly both apps were recorded by Pere Casulleras and members of the Museu de la Música de Barcelona as well as the Escola Superior de Música de Catalunya. Because of the complicated acoustical circumstances and the constructional conditions in the museum (e.g. a continuously running air conditioning system) this was a quite challenging and time-consuming process. Think of the fact that the very long fade-out sound of each single note was recorded, and also the sounds at key release. In spite of these circumstances, and due to faithful postprocessing, sample sets have resulted that deliver a realistic impression of the instrument and are a great pleasure to make music with. Using the version adapted to equal temperament, a large range of keyboard pieces can be played, but the meantone original has its own charm as well.
The sample sets are freely available at http://samplesets.esmuc.info resp. http://casacota.cat and can for example be used with GrandOrgue as well. We would like to express our thankfulness to the creators for giving permission to incorporate the WAV files in our apps, and also to the museum for maintaining and caring for this beautiful instrument.
About the Harpsichord
According to Wikipedia, three instruments of the Hamburg harpsichord builder Christian Zell have survived, one from 1728, one from 1737 and one from 1741. The instrument in the Museu de la Música de Barcelona is the 1737 harpsichord and has the following sounds:
|Lute Stop||affects 8' I|
The picture in the Gallery view of the apps, which shows the 1737 harpsichord at its exhibition place in the museum and served as a base for the app icons and for the app store artwork, is from the Wikipedia article. In the MIMO (musical instrument museums online) there is another nice photo. We used this photo when we crafted the background picture of the apps' Console views.
|William Edmund, Jigg in G Minor||YouTube|