Volume/loudness standard for LFE

In this article, we’ll lay out how subwoofers are measured in a multichannel setup. SoundID Reference for Multichannel supports a single LFE output, which gives the option to measure a subwoofer that is routed to a separate LFE channel. 

During the measurement, Measure app can take into account a +10 dB boost to the LFE channel and retain it when adjusting output levels if the option is selected. This is a cinema standard, that many multichannel engineers use in their workflow. In case it is not known if the subwoofers are set to +10 dB already, our software will help you adjust the output accordingly.

When a +10 dB boost has been set up for the LFE channel, then the rest of the speakers will still be adjusted to be equal with respect to the Center speaker. However, if you wish to have the LFE channel output at the same level as the rest of the speakers, then you can choose the corresponding option during the measurement setup for the desired results.

Multiple subwoofers

The LFE output is a single output channel. There are currently no individual outputs available for subwoofers. It is however possible to measure multiple subwoofers in your studio in parallel, as we understand the need for bass management. Currently, we can not guarantee an ultimate result for such a setup, as there is only one measurement step in place. 

Flowchart

Ideally, such a setup would look like this. In this example, two subwoofers are shown. 

Phase and placement

An individual approach to each subwoofer will bring the best results, especially in asymmetrical environments. However, measuring several subwoofers in parallel has shown that, as long as the subwoofers are not out of phase with each other and are at an equal distance from the Listening Spot, phase alignment will improve the sound.

How to measure multiple subwoofers

Taking into consideration the above, we recommend placing the subwoofers at an equal distance between the left and right speakers and letting our software calibrate. Keep the microphone in the Listening Spot - at ear height - during the LFE measurement step. Your subwoofers will now be measured and ready! 

Learn more: 

• Setting up with SoundID Reference Multichannel plugin
• Which formats are supported for multichannel speaker calibration?
• Speaker Volume Adjustment features in a multichannel measurement
• SoundID Reference multichannel speaker measurement troubleshooting guide

If you require additional assistance you can reach out to support by submitting a support request below.