Output channel when measuring subs? Left, right or left + right?

[Spennis]

Hi,

When measuring the frequency response of my two subs today, I noticed that the choice of output channel in REW gave a very noticeable difference in SPL output, even though I had disconnected the mains. How come, and which one should I choose?

The subs are connected to a MiniDSP, which is connected via a single subwoofer out on the AVR. The AVR is running in stereo mode with Audyssey turned off etc.

 

[John Mulcahy]

If you select left+right you will get twice the level since bass will be redirected from both channels. Use either left or right alone.

 

[Spennis]

Thank you.