Subwoofer Occasionally Fades In and Out

Mr. Mojo

I've noticed that my sub works about 80%-90% of the time but I notice that occasionally it appears to be missing. I notice this on blue ray and TV broadcasts. I'm sure it's missing as I will later rewind the same part of the movie and the bass is there where it wasn't before. It's an Infinity PS210 subwoofer hooked up with a subwoofer cable I got from monoprice to an Onkyo 605.
Any suggestions for fixing other then reconnecting the subwoofer cable on both ends?
Thanks for any help.

kawizx9r

How high is the LFE out on your receiver?

The only thing I can think of (that used to happen to me on an older Pioneer AVR) is that there were long bass-less passages in movies. This would cause my sub to turn off automatically (10-15mins auto shutoff feature) and I'd miss some bass notes that were just too low to turn my sub back on, but not low enough for me to forget that they were there if they didn't play.

You can also try just putting your subwoofer on an only ON feature. All mine had 3 options. An Off - Auto On/Off - ON

-Freddy

Willow

kawizx9r wrote: »

How high is the LFE out on your receiver?

The only thing I can think of (that used to happen to me on an older Pioneer AVR) is that there were long bass-less passages in movies. This would cause my sub to turn off automatically (10-15mins auto shutoff feature) and I'd miss some bass notes that were just too low to turn my sub back on, but not low enough for me to forget that they were there if they didn't play.

You can also try just putting your subwoofer on an only ON feature. All mine had 3 options. An Off - Auto On/Off - ON

-Freddy

What he said ^^^^^^^^^^^

kuntasensei

Make sure the subwoofer trim on your receiver is up near 0, then adjust the gain on the subwoofer itself to bring it back to the right level. If your sub trim is down below -4 or so, you may not be keeping enough line level to the sub to keep the auto-on going.

Also, make sure your speakers themselves aren't set to full range. The Audyssey setup on the Onkyos has an issue where any speaker that can go below 80Hz will get set to full range, in which case you're only sending LFE to your subwoofer, not redirected bass from the other channels. Set all the crossovers to 80Hz and that should keep enough bass going to your sub to keep the auto-on triggered. It will also give you more headroom on the receiver, since it's using vastly less power to drive your speakers, letting the subwoofer handle the load.

comfortablycurt

I'd have to go with everyone elses suggestions. I used to have the same problem with an old Pioneer sub that I had. I had the LFE output set to low, and during long passages without bass, the subs auto-off circuitry would activate. It would usually stay off until the next reasonably strong bass passage...quieter bass passages wouldn't suffice to turn the sub back on.

Try turning the sub level in your AVR up, make sure the front channels aren't set to large, then adjust the gain on the sub to get it level matched.

Mr. Mojo

Excellent suggestions.
I'll give these a try.
Thanks!

kawizx9r

Hope it works out, although I'm almost positive what I said might be the reason your sub cuts in and out. I've experienced it, otherwise try the other suggestions IE use another cable.

mmadden28

Just throwing this out there--could also be frequencies canceling each other out between the speakers (if set to full range) and the sub. And some of this can be dependent on and change with room position (both the sub and the listener)

Mr. Mojo, are you noticing these issues when you are sitting still or more when you move around a bit?

Mr. Mojo

mmadden28 wrote: »

Just throwing this out there--could also be frequencies canceling each other out between the speakers (if set to full range) and the sub. And some of this can be dependent on and change with room position (both the sub and the listener)

Mr. Mojo, are you noticing these issues when you are sitting still or more when you move around a bit?

When sitting.
I have Polk RM10s set to small with 100Hz crossover. Subwoofer is set to 120Hz crossover.
It's inconsistent. Sometimes a movie or TV plays all the way through with sub active and other times I notice the sub is missing. I rewind movie and sure enough, the sub is then active in that part of the film where it was previously missing. I notice more of a problem with TV and maybe it's because there's less low frequency bass to keep the sub active.

Mr. Mojo

kawizx9r wrote: »

Hope it works out, although I'm almost positive what I said might be the reason your sub cuts in and out. I've experienced it, otherwise try the other suggestions IE use another cable.

I would definitely try this but my sub does not have the "on" setting - just the automatic one.

mmadden28

I'm leaning towards what kawizx9r said in post #2. Perhaps check the sub output level from the Onk--up the dBs a bit. If you have to, turn the sub's own volume down if its too much bass. The signal may just be too low to keep the auto on 'on', or to turn it back on.