Originally Posted by Kurolicious
If your speakers are set to Small and crossed at 80hz, your sub is always playing bass below the crossover.
Read the footnotes regarding the Plus setting - "This may not, however, yield the best bass results. Depending on the speaker placement of your room you may actually experience a decrease in the amount of bass due to low frequency cancellations."
Possibly. Not completely sure though. If you look on page 45, where the manual describes the the difference between PURE and PURE DIRECT, it states: "With DIRECT, the only modifications added to PURE DIRECT playback are calibration of the sound field by the MCACC system and Phase Control effect. . . . PURE DIRECT plays back unmodified sound from source with only minimal digital treatment." I am unsure whether the "MCACC System" includes bass management because if it does, there is the possibility that bass frequencies could be cut off to the subwoofer when running PURE DIRECT and I'm trying to figure out if the PLUS control will keep the subwoofer active at all times. I just don't know
I think I'll contact Pioneer and see if they can get me something fully describing the PLUS mode.
EDIT: Spoke to Pioneer. Tech confirmed that the only way to guarantee getting the sub to activate with all sources is to engage PLUS mode, which bypasses everything else going on in the system and puts out a consistent low frequency signal to the sub that is not affected by bass management. It isn't a full range signal, like you can get from the speaker terminals -- it is a bass signal only, although he did not know what the high frequency cut-off was. Apparently Pioneer doesn't publish it.
For what it's worth, Pioneer's knowledge base actually proved marginally useful and seemed to confirm that the sub can be cut out with certain source material unless PLUS is used. One Q&A from the website:
"No subwoofer output with 2 channel sources.
[Q:] I setup the receiver and I had the subwoofer when I would listen to a 2 channel source, like a CD. I then ran the MCACC setup, for my Home Theater. Now when I listen to the 2 channel source, I no longer get the subwoofer to work.
[A:] The MCACC software will take readings and set the system to settings it thinks are the best.
After performing the MCACC setup, you should go into the receiver and make fine adjustments.
Press the receiver button, located underneath the display window.
Press the setup button, located on the right side of the remote (near the middle).
Arrow down to highlight Manual SP Setup and press enter.
Highlight Speaker Setting and press enter.
Arrow down to highlight subwoofer.
Arrow to the right to set the subwoofer to PLUS.
Press return and then press the setup button to exit.
With this change, the subwoofer will output sounds from all sources.
You may also need to make adjustments to the Channel Level to set the speaker levels to your liking."