About FireWire Bandwidth
FireWire bandwidth is shared between Apollo I/O streams, UAD plug-ins used within the DAW, and external FireWire hard drives. Available bandwidth also depends on the session sample rate; the higher the sample rate, the more bandwidth is consumed. FireWire bandwidth is displayed in the “FBW” meter in the UAD Meter & Control Panel application:
UAD Bandwidth Allocation
The UAD Bandwidth Allocation setting reserves FireWire bandwidth for UAD plug-ins used within a DAW (it has no effect on UAD plug-ins used in Console, nor when connected to the host computer via Thunderbolt). The default value (65%) a good starting point for most single-unit users; it should be adjusted according to your particular environment. Use the values in the table below as starting points when tuning the UAD Bandwidth Allocation.
Recommended UAD Bandwidth Allocation Values
| Sample Rate (kHz): | 44.1, 48 | 88.2, 96 | 176.4, 192 |
| Without external FireWire hard drive: | 75% | 55% | 40% |
| With external FireWire hard drive: | 50% | 30% | 20% |
| I/O buffer setting for best playback results: | 512 | 1024 | 2048 |
Note: When multi-unit cascading with two Apollo units, less bandwidth is available so external FireWire hard drives are not recommended. See "Multi-Unit FireWire Bandwidth" in the Apollo Software Manual for related information and recommended UAD Bandwidth Allocation values when multi-unit cascading.
To change the UAD Bandwidth Allocation setting:
1. Quit all DAW software and the Console application (UAD hosts must be quit to change this setting).
2. Open the UAD Meter & Control Panel application:
(Mac) The application can be accessed under the blue UA diamond icon in the OS X Menu Bar (at upper right of screen),or click its icon in the Dock.
(Win) The application can be accessed from the Windows System Tray (blue UA diamond icon), or select the application from:Start Menu>All Programs>UAD Powered Plug-Ins>UAD Meter & Control Panel.
3. Open the “FireWire” panel within the UAD Meter & Control Panel application. Access the FireWire panel by clicking the menu button in the UAD Meter window and selecting “FireWire...” from the drop menu, or type Command+F (Mac) or Control+F (Win) as a shortcut.
4. Change the UAD Bandwidth Allocation setting (shown below) by clicking the up or down arrows, or click+hold the value for a drop menu.
UAD Bandwidth Allocation Notes:
- Important: If switching to a higher sample rate, set the UAD Bandwidth Allocation BEFORE opening a session.
- UAD Bandwidth Allocation values in the table above are recommended as starting points for FireWire bandwidth tuning. Depending on external FireWire hard drive usage (e.g., how many audio tracks are being streamed), lower values may be needed for increased FireWire hard drive loads, or higher values can be used for increased UAD plug-in counts when FireWire hard drive usage is lower.
- To run more UAD plug-ins within a DAW, use USB, eSATA, or internal hard drives for audio session files instead of FireWire drives.
- The UAD Bandwidth Allocation only applies when UAD plug-ins are used within a DAW. FireWire bandwidth is not consumed by UAD plug-ins used within Console, nor when Thunderbolt is used for the host computer connection.
- (Mac) FireWire performance is better on some systems versus others due to the FireWire controller chips they contain. In general, newer Mac Pro, iMac, and Mac mini systems contain a superior FireWire controller chip and will deliver better FireWire performance than MacBook Pro systems. There is no simple method to determine which controller is used.
FireWire Bus Power
- The included power supply is required for Apollo operation. Apollo cannot be bus powered.
- Apollo does not supply bus power from its FireWire ports to other devices.
- When using a FireWire device that requires bus power, connect that device directly to a FireWire port that supplies bus power, such as the host computer itself, or an externally powered FireWire repeater that is specifically designed to supply bus power.
Combining Apollo with other FireWire devices
- As a general guideline, Apollo should be powered on after all other FireWire devices on the bus are powered on (except when used with UAD-2 Satellite FireWire, as noted below).
- If UAD-2 Satellite FireWire is on the same FireWire bus as Apollo, the UAD-2 Satellite must be powered on after Apollo is powered on.
- See the FireWire Multi-Unit Cascading article for related information.
Maximum of two UAD FireWire devices
- Concurrent use of up to two UAD FireWire devices (Apollo and/or UAD-2 Satellite FireWire) together in one computer system is compatible.
Combining Apollo or Apollo 16 with non-FireWire UAD Devices
- Apollo or Apollo 16 can be combined with UAD-2 PCIe, UAD-2 Satellite FireWire, and/or UAD-2 SOLO/Laptop (within the other requirements on this page).
- Up to six UAD-2 devices can be combined together in one computer system (within the other requirements on this page).
Combining Apollo or Apollo 16 with UAD-2 Satellite FireWire
- If UAD-2 Satellite FireWire is on the same FireWire bus as Apollo or Apollo 16, the UAD-2 Satellite MUST be powered on AFTER Apollo or Apollo 16 is powered on.
- Combining one UAD-2 Satellite FireWire with one Apollo or one Apollo 16 together in one computer system is a compatible configuration.
Mac Pro FireWire Ports
- Mac Pro systems have FireWire ports on the front and rear of the computer. Connect Apollo to a FireWire port on the rear of the Mac Pro. The front panel FireWire port is untested.
FireWire Bus Tuning
- To maximize FireWire bus performance, the UAD Bandwidth Allocation may need to be adjusted. See the FireWire Bandwidth info at the top of this article for more information.