way to capture LFE processing differences?

[thothsong]

In comparing two sound modes on my sound system, I can hear a difference in LFE processing between them, one sounding a bit deeper in certain scenes. If I capture peak SPL of a few seconds of an LFE event using RTA with default settings, the two modes basically measure the same. So I think the difference is either due SPL differences below peak, or duration. Is there some way to measure the difference using REW?

 

[thothsong]

To I think partly answer my own question, changing RTA to use Forever averages instead of None gives me better insight.

 

[John Mulcahy]

An alternative would be to make response measurements of the LFE output (connecting it to a soundcard input) in the different modes and see if they are any different.

 

[thothsong]

Thanks for the response. The two sound modes are called Standard and Surround. In a simple frequency response of the LFE channel, Surround is uniformly ~2 dB louder than Standard. The particular content I'm looking at is DD+ Atmos. Standard sound mode uses 7.1.4 speakers, and Surround uses 11.1.4, so I had expected variation in floor level speaker utilization, but had figured LFE would be consistent. But in an example LFE event I measured using Forever averaging, Surround flipped to be 2-3 dB quieter than Standard. Seems to be very content dependent.