[Metfit77@gmail.com]

Hi,
I have two triple OB subs. Both amps have all the same settings, but the right channel seems to occasionally bottom out, even at moderate volumes. It does this more frequently during movies vs music. I have tried various settings on the a370peq amp, but nothing seems to increase or decrease frequency. I have the volume on the amp set around 11oclock.
Any ideas on what could be causing this? The sub on the left side has never done this.

[WGH]

What movies? Many of the current movie releases have sub killer bass if played back at theater levels.

[dflee]

Try switching the amps left to right and see if it still happening in the same sub.

Don

[jlucas]

You say bottoming but do you mean just audible distortion?

[SoCalWJS]

What “Same Settings” are you using?

HT/LFE bass can be quite a challenge for any Sub. If your settings aren’t correct for that purpose, you are asking for issues, especially in some LARGE rooms.

**** Also, if problem follows after switching Left for Right, check that all of your wires are connected correctly. ****

[DannyBadorine]

Have you verified that they are wired correctly?  If one side is going it then I think something might be wrong with the wiring.

[Hobbsmeerkat]

It's kind of a known thing for the OB subs to not be ideal for HT use.
You might want to adjust their extension to 28Hz and engage the rumble filter. That should prevent over-excursion in movies.

If you still need/want the really low end, use sealed subs to augment the lowest octaves. Esp below 30Hz, where they will be most effective in home theater use.

Still odd that only one driver seems to be acting up.

[WGH]

...but the right channel seems to occasionally bottom out, even at moderate volume....
Any ideas on what could be causing this?

Two ideas and you won't like the second

1.) The woofer is really bottoming out because it can't do 20 Hz no matter the volume. If you use an AVR or processor check the advanced menu to see if you can adjust the bass when using the .1 LFE, that way the processor can adjust the bass for movies and the music settings are not affected.

Anthem Room Correction could fix this with a higher Low-Frequency Extension and Slope settings for the .1 Low Frequency Effects output


2.) You have a damaged woofer from repeated over extension. The woofer may not actually be bottoming out but sounds like it because one of the leads to the voice coil is making an intermittent connection. At a certain loudness or low frequency the connection breaks, the driver cone stops working and returns to center, then re-connects and the cycle repeats making a rattling sound. The only solution is a new driver.

[Danny Richie]

9 times out of 10 this issue is related to a polarity flip of the sensing coils.