The Studio window, accessed from the Windows->Studio menu item of any song window, is used to associate MIDI ports with Sequitur devices. When you make an association between a MIDI port and a device, you are really making an association between a device and the Sequitur filter for that MIDI port. For example, if you have a song with a single track, and that track has an output filter labeled "MIDI_port_1", then there will be a MIDI port labeled "MIDI_port_1" in the studio window, and associating a device with it is actually setting that device for the track that uses the filter for that MIDI port.
This is mostly a convenience: Once a track has a device, then the Program Change strip view can use the actual patch names from the device, and the Control Change strip view can use the actual controller names from the device. There are two cases where this is more than a convenience:
The Studio window displays a list of all MIDI ports, whether the port is an In our Out type, the device associated with the port, and the current label.
9.1.1. The MIDI Port Column
This column lists the name of each port. The MIDI port will be either a hardware port or currently running software application. Software applications are generally fairly obvious, for example ObjektSynth appears as ObjektSynth. Hardware ports are usually a little more cryptic; in this screenshot, the /dev/midi/sonic_vibes/1 refers to the hardware MIDI port of a Turtle Beach Daytona PCI sound card, and the UX256/ items refer to a Yamaha UX256.
The MIDI specification states that a single MIDI port can address up to 16 channels. Clicking on the expand box to the left of the MIDI port name will display all 16 channels for that port. Any changes made to the unexpanded row is a shortcut that changes all 16 channels together. However, expanding the row allows you to associate different devices with different channels of the MIDI port (if that's how your studio happens to be set up).
9.1.2. The Device Column
This column lists the device currently associated with a given MIDI port. Change the device by selecting the appropriate row, then selecting the desired device from the Device: menu button at the bottom of the window. If you own a device that is not listed, either visit the Device Download page at the Angry Red Planet website, or create the device yourself.
9.1.3. The Label Column
By selecting a MIDI port row and then entering a label, the label will be used in place of the MIDI port name (or device name if one is specified) throughout Sequitur. This is a minor convenience.
9.2. A Note on MIDI Ports in BeOS
While it's comfortable to think in terms of familiar MIDI ports, it's also a little misleading. Most operating systems, for example Windows or MacOS, have a fixed number of MIDI ports available, which corresponds to whatever MIDI interface hardware is installed. Sound cards will often supply a single in and a single out port, but most musicians have additional hardware that supplies them with more MIDI ports.
In BeOS, MIDI ports are actually called MIDI endpoints. This difference in terminology reflects the fact that both hardware and software determine the currently available MIDI endpoints. Applications can dynamically create and delete MIDI endpoints -- so the list of MIDI ports in the Studio window might change even as you're watching it. Sequitur uses the term 'MIDI port' only to avoid confusion for experienced electronic musicians; this term is not a completely accurate term.
Occasionally, certain MIDI port rows might be displayed in red. This indicates that the MIDI port existed at some point, but no longer does. Sequitur can still associate devices with these transitory MIDI ports. If you have done so, but later decide to remove the association, you can select the MIDI Port->Delete menu item to remove the association between the MIDI port and device. The dynamic port, created by an application, will return the next time you use that application.
