Subwoofer not working until I change the volume on the back

[Mike Coenen]

As the title suggests i've got a rather weird issue with my sub; a canton sub 12.

The sub is connected to an Onkyo TX-NR828 by a subwoofer cable ( Y RCA ). I have also tried a normal RCA cable connected to the mono port on the sub, to rule out cable problems.

Here's a step by step:

1) I turn the subwoofer on myself, or the sub is in standby and detects a sound signal. The light of the sub turns green, indicating it's on.
2) There is no sound coming from the sub. I can watch a movie, play a song, or sent a test signal from the avr to the sub - but no sound at all.
3) At this point I have tried disconnecting the cable once and lightly tapping it, but the sub will not come on this way either. I would expect at least some noise.
4) Here's the kicker; I twist the volume on the sub to max for a few seconds and then turn it back to what i had originally set it ( this is -16db and the level calibration in the avr is set to 0db. This setting makes sure the windows don't rattle ). And now i suddenly have sound. Movies, music and the test tone work now.
5) The sub will continue working just fine until it's been on standby for a several minutes or turned off.

I'm confuzzled ....

 

[Basshead81]

Sounds like a problem with the amplifier.

 

[j_garcia]

Try adjusting the sub level in the receiver up and the level on the sub itself down (to compensate, back to the same level). If the sub comes on, you either have too low of an output voltage on the receiver's sub pre-out and/or the sub's input sensitivity wants a higher voltage OR the amp on the sub has an issue as mentioned.

 

[Mike Coenen]

Try adjusting the sub level in the receiver up and the level on the sub itself down (to compensate, back to the same level). If the sub comes on, you either have too low of an output voltage on the receiver's sub pre-out and/or the sub's input sensitivity wants a higher voltage OR the amp on the sub has an issue as mentioned.

I set it to +5db in the avr, the test tone didn't start, but i started a movie and after a few minutes the sub started to do it's thing. I'm not sure if this means that it's fixed now. I mean is there still a defect? This stuff is pretty much all brand new.

 

[j_garcia]

Sounds like the previous settings were too low for the sub's input voltage. If it starts doing it again with this setting, then I'd probably have the sub's amp looked at.

 

[Mike Coenen]

It seems that this has solved my problem, but i really don't understand it. Apparently the avr pre out is not outputting enough voltage to power a sub, why would they make an avr that can't power a sub ; And this is at least a mid range avr. Is is considered normal to have to set higher db on the avr to get it working?

I can't return this avr anymore to get a better one with higher output, but i read/seen so many reviews on this thing and not a single one mentioned this could be an issue. Is there some kind of hardware i can add in between the avr and sub that could boost the voltage slightly, without blowing **** up of course.

Edit:

I actually got the onky tx-nr828 partly because of this article ( and several other sources ): http://www.audioholics.com/how-to-shop/best-midrange-receiver-2013. Went with onkyo because of brand loyalty in the end.

Also, could this damage my sub/avr in anyway?

 

[j_garcia]

It is the combination of the two and I'd say the issue is more likely the sub than the receiver. Onkyos are usually pretty good in terms of output voltage on the pre-outs, or at least I've not had issues with them in the past. So the sub's amp may require more voltage than average and the combination of that sub and your receiver creates the issue.

*Edit - Can't find a manual online for that one and Canton doesn't list the input sensitivity.

 

[Mike Coenen]

Just tried it again and it took at least 10 minutes before it finally kicked in, damn it. Set the avr to +8 now, but i think the amp is not working so well ...

 

[j_garcia]

Most likely a problem with the sub's amp then. Sorry man, that sucks.

 

[Mike Coenen]

Going to try another avr somewhere, think my neighbour has one. Heard i can also test it with a cd/dvd player by hooking the rca cable into that.

If that doesn't work i can send it to the service center. At this point i hope it won't work, because it would be my avr that's borked...

Thanks again for all your help.

 

[j_garcia]

If your receiver has pre-outs for any other channels, you can use those too, just need to set them to Large.

 

[Mike Coenen]

At +8db it in the avr it seems to come on on it's own fairly fast, have noticed that on low volume ( below 50 ) it has a harder time turning on as well.

Contacted onkyo now as well. I can't be certain it's the sub or the avr or santa coming to town =/

 

[TLS Guy]

At +8db it in the avr it seems to come on on it's own fairly fast, have noticed that on low volume ( below 50 ) it has a harder time turning on as well.

Contacted onkyo now as well. I can't be certain it's the sub or the avr or santa coming to town =/

Switch off auto on. This feature on subs often does not work well. If that does not cure it, it will be the sub. Most are the most trouble prone pieces of garbage around.

 

[Mike Coenen]

Switch off auto on. This feature on subs often does not work well. If that does not cure it, it will be the sub. Most are the most trouble prone pieces of garbage around.

It's off. It helps.

It's still somewhat weird though, it's like the AVR needs to supply a bit of startup juice ( that's why i have set it to +8db now ) before the sub realizes it has to start pumping the bass. It only needs to do this once though and with the auto on thing turned off, it will be fine.

I guess i fixed it for now. Stupid thing imo.

 

[j_garcia]

Like TLS said, if it is still doing it with auto on turned off, then there's a problem with the sub. It is already on, so the problem is it recognizing the signal coming in.

 

[Mike Coenen]

Like TLS said, if it is still doing it with auto on turned off, then there's a problem with the sub. It is already on, so the problem is it recognizing the signal coming in.

It's been working all weekend, guess it's fine now.

 

[Mike Coenen]

It seems to work at random, i should have said. It's been working fine for a few days now and suddenly last night it stopped again and this morning it worked fine again. Now I have both Onkyo and Canton asking me to send the sub and avr in for testing/repair, because no one seems to fracking now where the problem lies.

Why did i ever invest in this ... thousands of euro's and nothing but crap.

I need to figure out which device is the problem here =_= how do you test something that works one day and doesn't the next.

 

[TLS Guy]

It seems to work at random, i should have said. It's been working fine for a few days now and suddenly last night it stopped again and this morning it worked fine again. Now I have both Onkyo and Canton asking me to send the sub and avr in for testing/repair, because no one seems to fracking now where the problem lies.

Why did i ever invest in this ... thousands of euro's and nothing but crap.

I need to figure out which device is the problem here =_= how do you test something that works one day and doesn't the next.

That is what test gear is for. However since touching the volume control on the sub brings the sub back to life, it is the sub. Moving the volume control could have no impact on the receiver, but only the sub.

It will be the sub.

 

[Mike Coenen]

That is what test gear is for. However since touching the volume control on the sub brings the sub back to life, it is the sub. Moving the volume control could have no impact on the receiver, but only the sub.

It will be the sub.

Ok... Sending sub to the service center, please let that be it. Without an avr i'd be even more screwed.

 

[Mike Coenen]

They tested the sub and found nothing wrong with it. I've been running with another sub, connected the same way with no problems either. I don't really see a reason to send the receiver in for testing.

It still probably has to do with the signal it gets not being enough for the canton, but it doesn't seem like i'll be able to solve this.