Explained below is a definition of the Line 6 Audio-MIDI Control Panel. It explains and defines the function of each setting within the application.
The "Driver" tab
Driver Operating at:
The "Driver operating at:" status actually shows the sample rate and bit depth of the data going through the USB cable and the hardware. For X3, the hardware always runs at 48000 Hz, 24 bit regardless of what the driver is doing, so you'll always see 48k, 24bit.
From the Gearbox Manual page 3.4
Driver Operation indicator:
TonePort & GuitarPort devices - Displays what sample and bit rate the current device is operating at(or with no text if not in use).
Note: PODxt devices do not utilize this feature and therefore no text will appear here when a PODxt is the selected device. These devices run at a fixed sample rate which is why you'll see the Sample Rate Converter light always on when viewing the Control Panel with a POD XT device connected. The POD XT is always converting from the custom rate to it's fixed sample rate.
Similarly, the SRC light will always be on for X3, unless you're running the driver at 48kHz.
The "Lock Format" check box affects two things.
1)All WDM applications
2)The hardware sample rate, if it isn't already locked by the hardware (like X3 or XT).
From the Gearbox Manual page 3.4
Lock Driver Format: When checked, this forces the Line 6 audio driver to operate at the Sample
and Bit rate settings entered in the two fields below (as opposed to following the sample rate requested
by a host audio application).
Note: Lock Format doesn't affect the ASIO driver. All sample rates will still work for ASIO even if Lock Format is checked. With TonePort devices, Lock Format will lock that hardware to the given sample rate. If ASIO software asks for a different sample rate, our driver will perform the necessary Sample Rate Conversion.
The ASIO Settings section are the displayed settings of what you are actually running your ASIO driver at.
From the Gearbox Manual page 3.3/3.4
If you are running audio software that is using this Line 6 device as its
ASIO sound card, the name of the software will appear here. If not in use by an ASIO software, “none”
is displayed here as shown.
Default Buffer Size:
The ASIO buffer size in use. Note this field is only active when in use by an ASIO application. As your audio software documentation will likely tell you, the ASIO Buffer Size will affect the “responsiveness” and “latency” of the audio. The lower the setting, the faster the response, but with the trade-off of higher processor usage and the risk of audio dropouts. Raise the value if you are getting inconsistent playback or recording in the audio software. Basically, 512 is generally a good average setting.*
Default Bit Depth:
The ASIO bit depth in use. Note this field is only active when in use by an ASIO application. It is best to use the highest bit rate your ASIO software will support to ensure high quality
Sample Rate Converter:
TonePorts support 44.1 and 48 kHz sample rates natively. Some TonePorts also support 88 and 96 kHz sample rates by way of an internal sample rate converter. This indicator lights up to show you when this converter is active, which can be any time your ASIO software is requesting a different sample rate than what your device “natively” supports. TonePort UX8 supports 44.1, 48, 88.2 and 96 kHz sample rates natively, meaning that these sample rates are not converted.
The Inputs and Recording tab:
From the Gearbox Manual page 3.5:
Input Source Select:* This is a mirrored control for the Source Select within the GearBox application where it allows the user to select which physical input is used on the device. Note that this control is ONLY selectable when the GearBox software is not in use by the current device. When GearBox is in use, it remains grayed out, but displays the current Source that is selected within GearBox. When Gearbox is not in use by the selected Line 6 device, this Input Source Select, like the Source Select in the GearBox application, offers a list of input options.
GuitarPort and PODxt devices are always “fixed” to only route their “instrument” 1 /4 input signal into GearBox. When a GuitarPort or PODxt is the selected device, this Input Source Select list offers
only “Instrument” as the source.
TonePort UX8 has a larger set of options - see the next section for its Inputs & Recording tab.