Originally Posted by Jeff Permanian
Most people end up at 1/4 - 1/3 of the LF Adjust with the sealed subs for a flat response in room (ported 0 - 1/4). However, seems that when using auto room correction, people have getting the best results from having the LF adjust all the way down and then turning it up after room correction. Because subwoofers typically have higher max output on the topend vs the lowend, you end up with increased head room with lower LF Adjust.
I used a slightly different process, which was to have the LF Adjust set how I planned to use it prior to calibration. That said, I am using the Multi-Sub Optimizer software to create biquad filters to import into the output channels of a miniDSP. Since I wanted to have the subs set up with the response it was expecting, I figured that included setting the best LF Adjust setting for my room prior to optimization
. Again, this is not the case of Audyssey neutering the bass. Just in case I made a bonehead move, let me tell what I did.
I am using three pairs of equidistant subwoofers.
Subwoofer 1: 4000ULF-ST behind the screen wall.
Subwoofer 2: SubMersive HP on the side walls.
Subwoofer 3: SubMersive HP+ Master & Slave on the rear wall.
For Sub 1 and Sub three, they have the LF Adjustment, so I measured with REW for each sub-woofer pair independently, with the LF Adjust dial at each setting. I used the LF Adjust setting that resulted in the best response. In both subwoofer pair cases, there were dips in the response that were smoothed out when the LF Adjust was increased. For the 4000 ULF's, the response was with the LF Adjust at 9/10, and for the SubMersive HP+, the best response was with the LF Adjust at 10/10. I saved the measurement sets for future reference.
The Multi-Sub Optimizer measurements were taken with these settings, and the optimization performed well, smoothing out the combined response for all three sub-woofer pairs in the room. I then ran Audyssey, but using the Denon/Marantz MultEQ app, I turned down the sub-woofer channel correction to 20 Hz, essentially turning it off.
The results sound great, but let me know if this was a good plan, given the tools and process noted above.