Help Please my subwoofer never outputs anything

[audiochris]

Hi Guys, I am new to this forum and wonder if anyone could help or advise me. I have had my setup 5.1 for a couple of years but my problem is my sub never comes on when it should. So to start from beginning my setup for the 5.1 system is as follows

Front x 2 Mordaunt Short Aviano 8
Centre x 1 Mordaunt Short Aviano 5
Surrounds x 2 Mordaunt Short Aviano 8
Sub x 1 Mordaunt Short Aviano 9

Receiver 1 x Onkyo TX NR414

I have tried every setting under the sun on both the receiver and the sub but to no avail. The sub does come to life occasionally when watching a movie and it even come on the other day when playing music from PC but it soon goes off again. I have tried adjusting crossover on amp and have it at max on the sub so there should be no interference but no matter what I try it never produces bass. I have check and the sub always receives a signal as i watch it go from red to green as soon as anything is played through the system but it does not output any bass. Don't get me wrong on the odd occasion it does decide to produce something it is awesome and the bass is astonishing. Any help from you guys would be very much appreciated as I am at my wits end trying to get it to work.

 

[Dr. Bob]

I don't know much about subs, but here's one thing to check for. On my sub, I can switch it to "off", "on", or "auto." On "auto", it only comes on when it detects a (sufficiently large) signal. If you have such a switch, try setting it to "on" and see if that makes a difference.

 

[audiochris]

Many thanks for your reply Dr Bob. I have tried this previously but it still refuses to kick in regardless of this switch. When I have it on auto, as soon as it gets a source it triggers to green but still no output. I will try again leaving to on but sure this will not make a difference. Thanks again for the reply much appreciated.

 

[TLS Guy]

This is a tough one. There is no proper user manual available, and the set up guide tells you nothing useful.

That so called sub is not. It only extends to 35 Hz so technically it is a bass module.

All I have to go on is the picture of the plate amp. Now you say that when it receives a signal, the stand by light goes from red to green. So I assume this sub has an auto on feature, that by the look of the controls is not able to be defeated.

Since the sub does not produce sound when the color of the standby light changes color, I suspect this unit is a lemon.

The only thing I can suggest is to try two things.

First connect a CD player directly to the line ins. This should have enough power to drive the sub. If you hear nothing and the light goes green, then the sub is a dud.

If you get sound, then turn up the output level in your receiver speaker set up menu and see if that does the trick. If not then your receiver is defective. We have had this complaint with Onkyo receivers before and a lot else besides. But intermittent LFE output is a complaint I have fielded before from Onkyo.

So you need to find out which unit is at fault.

If the CD directly connected produces consistent output from the Avio 9 then your problem is the Onkyo.

If you get no, or intermittent sound from the Avio 9, then that unit is defective.

One piece of advice. Avoid subs from Europe like the plague. They are poor performers all around. American subs are much preferred.

The fact you hear nothing from the Avio 9 when the light turns green leads me to strongly suspect the sub in the first instance.

 

[chas_w]

Are your speakers set to small or large in the Onkyo? If they are set as large you might want to try small with an 80hz crossover to see if that helps.

 

[audiochris]

Thanks TLS that is a great reply and I will look into the trying of the sub on a different source. One thing though when I take the sub cable out of the amp and tap my finger on the end I do get a dull thud each time which is why i did not think the sub was at fault. Also thanks Chas for your reply but I have tried every single setting within the amp and sub to see if anything will make a difference including all crossover settings and large to small on every speaker but still no output. It just comes on when it feels like it and this is mostly during movie playback rather than when listening to music via PC.

 

[TLS Guy]

Thanks TLS that is a great reply and I will look into the trying of the sub on a different source. One thing though when I take the sub cable out of the amp and tap my finger on the end I do get a dull thud each time which is why i did not think the sub was at fault. Also thanks Chas for your reply but I have tried every single setting within the amp and sub to see if anything will make a difference including all crossover settings and large to small on every speaker but still no output. It just comes on when it feels like it and this is mostly during movie playback rather than when listening to music via PC.

That piece of information makes it a bit more likely to be the Onkyo. However doing that test you describe gives a sudden high voltage peak, so the signal detector in the Avio 9 my still be at fault.

One thing I'm certain of is that either the Onkyo or the Avio 9 is defective, and my test plan will tell you which.

 

[slipperybidness]

One piece of advice. Avoid subs from Europe like the plague. They are poor performers all around. American subs are much preferred.
.

LOL. That may be the first time I've ever seen TLS say that an American piece of gear is superior to European gear

To the OP: Have you tried a different cable? If you are lucky, it could be a faulty cable.

Otherwise, do the test that TLS suggested and report back.

Has the problem existed for the 2 years that you have been running this system? Or did it just start this problem all of a sudden?

 

[audiochris]

Thanks Slippery yes have tried a couple different cables just in case but I'm not hopeful on this. The problem has been since the very beginning and because i was a newbie to the 5.1 set up i honestly thought that i must be doing something wrong or maybe it was a setting in the receiver. As soon as I have time I have a stereo amp in the loft so will get this down and try to wire it into this amp via the high level connection and see if I cab get anything that way. I will report back as soon as I can try this out but as I say I am not hopeful at all and chances are this sub was faulty since day 1.

 

[markw]

Wait a minute... You've had this for several years and the sub has never worked? Did I misread something here?

 

[audiochris]

Hi and thanks Mark. Yes correct the sub is coming up for 3 years old and has only worked on the odd occasion and then goes off again after not too long approx 10 minutes. The sub always receives a signal though and clicks on at the light but that's it nothing more. I will get a test done asap and report back.

 

[markw]

Do that test TLS guy had you try where you plug something into it to see if it works. IMNSHO, it sounds like it's fried and there's not much you can do about it now except replace it. Warranty is long gone.

 

[TLS Guy]

Thanks Slippery yes have tried a couple different cables just in case but I'm not hopeful on this. The problem has been since the very beginning and because i was a newbie to the 5.1 set up i honestly thought that i must be doing something wrong or maybe it was a setting in the receiver. As soon as I have time I have a stereo amp in the loft so will get this down and try to wire it into this amp via the high level connection and see if I cab get anything that way. I will report back as soon as I can try this out but as I say I am not hopeful at all and chances are this sub was faulty since day 1.

No, connect a CD player to the line inputs. Any device with line level output will do. The high level and line level inputs do not use the same circuitry.

I'm still unsure whether this is a sub or receiver problem. I know I have dealt with more than one case of intermittent or no LFE out on Onkyo receivers, so we need to be sure where the problem is. It is crucial to know if your unit produces output with a signal at the line level inputs.

I'm pretty sure you will be replacing one unit or the other and for your sake we need to be certain the correct one goes to the recycling center.

 

[TLS Guy]

LOL. That may be the first time I've ever seen TLS say that an American piece of gear is superior to European gear

To the OP: Have you tried a different cable? If you are lucky, it could be a faulty cable.

Otherwise, do the test that TLS suggested and report back.

Has the problem existed for the 2 years that you have been running this system? Or did it just start this problem all of a sudden?

Well I have posted frequently how useless European subs are. In fairness is not all their fault, as there are few individual dwellings, so shared walls are very common. Complaints from neighbors gets your gear confiscated.

 

[audiochris]

Thanks for all of your help today it really is appreciated. I will certainly follow the advice given and run a test tomorrow and report back. Thanks again

"Be Lucky"

Chris

 

[TLS Guy]

Thanks for all of your help today it really is appreciated. I will certainly follow the advice given and run a test tomorrow and report back. Thanks again

"Be Lucky"

Chris

It is our absolute pleasure to help someone like yourself. Lately we have had a surfeit of idiots who won't take advice and have no appreciation of the effort we put in to help them.

I know we will be able to help you and will be glad to do so.

 

[ariche503]

Wish threads and sites like this existed back in the early 90s when my sub died...or at least I thought it did.

 

[audiochris]

Hi all, have done some testing and reporting back. I could not find in the loft my CD player so what i did was connect from my macs headphone output a cable which is 3.5mm headphone jack into iMac headphone to 1 x L/R line out into subs L/R line ins and hey presto it didn't come on straight away but then stayed on. From this connection after messing around a bit it works far better not on AUTO but sub switched and left onto the on position. Providing I leave it on the on setting it will fire up as soon as I play anything from iTunes regardless if it is a bass track or not it stays on and outputs a thunderous noise which I have not heard for a while LOL. So I am pretty much lost as to why this does not output (well occasionally it did) from the Onkyo receiver.

As I am getting better results from this connected to the mac my question is is there another way to connect the sub to the Onkyo. To be perfectly honest even if i dont get the 0.1 track when connected to the Onkyo i don't mind I would just be glad to get the things working together.

I have now left the sub connected to mac for about an hour with nothing playing and as soon as I play a track now its on. I have also switched everything off and on several times and providing the sub is switched to "ON" it fires up no problem.

"Be Lucky"

Chris

Further update: After all this switched on again just now and again nothing outputting so guess I was just lucky this morning.

The subs a dud so ill have to deal with it.

 

[audiochris]

Hi All, just updating this for future reference for the forum. After doing lots of testing and trawling the web for information a lot of other people with Mordant Short subs have a similar or identical problem. It is highly likely that the fault is the relay switch inside on the PCB. This makes complete sense as the sub is receiving a signal every time by way of the light coming on and clicking but not switching As it is not switching no power is being sent. Also when I give it a sudden bit of volume it does sometimes come on suggesting that is just enough to get it to switch and send power. Im hoping to find a decent audio engineer who will be able to replace or bypass the relay switch and hoping this will be cheap enough to do and most definitely worth while as this sub was not cheap.

Thanks to everyone who helped with this and prompted me to test and look deeper into the issue. I have already learnt a fair bit from the advice given. People that give up their own spare time to help others thank you very much.

"Be Lucky"

Chris

 

[TLS Guy]

Hi All, just updating this for future reference for the forum. After doing lots of testing and trawling the web for information a lot of other people with Mordant Short subs have a similar or identical problem. It is highly likely that the fault is the relay switch inside on the PCB. This makes complete sense as the sub is receiving a signal every time by way of the light coming on and clicking but not switching As it is not switching no power is being sent. Also when I give it a sudden bit of volume it does sometimes come on suggesting that is just enough to get it to switch and send power. Im hoping to find a decent audio engineer who will be able to replace or bypass the relay switch and hoping this will be cheap enough to do and most definitely worth while as this sub was not cheap.

Thanks to everyone who helped with this and prompted me to test and look deeper into the issue. I have already learnt a fair bit from the advice given. People that give up their own spare time to help others thank you very much.

"Be Lucky"

Chris

Well, that sub may not have been cheap, but it does not even extend to 30 Hz. That sub is not worth spending a lot of money on.

If you defeat the turn on relay, then the sub will be on when plugged in, so you will have to unplug it while not in use. Many of these sub amps are fire hazards, and so you should not leave the home with the thing plugged in.

To make it easier a mains on off switch might be able to be installed.

Your other option is replace the plate amp. This will involve carpentry.

The other option is to connect the driver directly to an external power amp you could purchase.

I would seriously consider getting a decent sub and ditch that POS European Bass Module.