If you are running a version of Logic Pro prior to 10.2.1:
Please read the “Using Multiple OSC iDevices/Apps with Logic Pro“ section below before you try to setup lpTouch.
If you are running Logic Pro X 10.2.1 or higher:
Logic Pro X 10.2.1 (and higher) appears to have resolved the problem that was happening when using multiple OSC controllers, provided you follow the recommendations here.
If you plan to use lpTouch on both the iPad and iPhone or iPod touch, or have already been using Logic with other OSC controllers like Logic Remote or TouchOSC, you will need to do a few additional steps - listed below - if you want to switch back and forth between different apps. Tap the orange button if you want more in-depth information about this issue.
These steps must be done if you are running a version of Logic Pro prior to 10.2.1 and want to switch between multiple OSC apps. (It appears that this problem does not occur with Logic Pro X 10.2.1 if you follow these guidelines.) However, if you do experience erratic behavior, the remedy below may get things working correctly.
Logic's inability to reliably handle multiple OSC control surfaces (prior to Logic 10.2.1) makes it challenging to use multiple OSC controller apps side-by-side. To switch from using one OSC controller app to another, you must do these steps every time:
If you suspect your control surface preferences are corrupt, or you just want to absolutely make sure you are starting with a clean slate, then you should follow this procedure to delete the existing control surfaces preferences settings file. Logic will create a new version of this file the next time it exits. Unfortunately if you have a corrupted file and that file contains your favorite control surface customizations that you laboriously slaved to create, those will be lost. This is one reason why a backup after making such additions is essential.
Logic Pro X has some differences from Logic Pro 9 that require some manual workarounds to achieve consistency with lpTouch, primarily related to lpTouch's Aux channel faders.
On the iPad, lpTouch's Main-Volume screen two faders on the right are defined by Logic's original OSC control surface driver to show Logic's first AUX channel and the Master volume control. (On the iPhone, these are on the Master Aux screen). Prior to Logic Pro X, a typical project (including most templates) assigned a "send effect", like reverb, to the first AUX channel. This made it convenient to adjust the overall effect level using lpTouch. Likewise, Logic's original OSC driver assigns the two right side faders on lpTouch's Pan-Sends screen to AUX 2 and AUX 3 levels. Again, prior to Logic Pro X it was typical to assign send effects to AUX 2 and AUX 3.
Logic Pro X makes extensive use of AUX channels to implement the new Track Stack feature, and Logic Pro X's instrument and channel strip "patches" also can include AUX channels. If these are added first to a project, then those will use AUX 1-3 and lpTouch will display whatever those stacks or patches have assigned to those AUX channels. This may or may not be what you wanted. And since the project starter templates have a number of instruments and channel strips already in place, AUX 1-3 will probably already be assigned before you open the new project.
If you want to retain a consistent assignment to lpTouch's auxiliary faders, then AUX 1-3 need to be added to the project and assigned to their task (like reverb) before any "patches" are added. The easiest way to insure this is to alter your starter templates accordingly. If you regularly use Logic's built-in starter templates, consider creating personal versions by modifying the built-in ones you use.
The same project but starting first by adding three AUX channels: "reverb", "EFX1", and "EFX2". The drummer and piano software instruments were then added. Since the three AUX channels were pre-assigned, subsequent track additions (or deletions) will not cause Logic to display different AUX channels on lpTouch. It is recommended that you save a template project with your typical AUX channels assigned in this manner.
Situations may occur where Logic Pro X either fails to update the function of lpTouch's three auxiliary faders, or updates them with the incorrect assignment. It can also assign the wrong channel to the lpTouch Master fader (far right fader on Main-Volume screen). Whether this is intentional or a Logic Pro X flaw is unclear, but it is different behavior from Logic Pro 9. We have, however, had good results by "refreshing" lpTouch's screen by either momentarily switching to a different screen (say from Pan-Sends to Channel Strip and back). Alternatively, changing some aspect of the channel in question in Logic Pro X, like toggling the AUX from stereo to mono input and back will also cause a refresh.
Logic incorrectly updating lpTouch after a channel deletion from Logic's mixer - Aux 1 channel fader shows "Click".
Display corrected after "refreshing" by selecting lpTouch's EQ screen tab and then back to the Main-Volume. Changing tabs or channel settings in Logic's mixer will often cause Logic to send the proper information.