REL TZero Sub no longer working...advice needed please...thanks

CCMustard

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Hi,

I have a REL TZERO sub which no longer works. It powers on but when tested via a tone test the sound is very very low. I tried both sub woofer channels on my Denon AVR X2300W AMP so think it is definitely the sub. I generally don't push the speakers (65%) that much so would surprised if it is blown. The sub woofer control volume knob was always set in the middle and left alone.

Anybody know what is likely wrong and if it is worth repairing? Would be a shame to bin it as it is only 4 years old from new. It is very disappointing that it has failed so soon. Local recommended repairers would be useful too if you know of any or any other ideas.

Thanks.
 
So you have connected the subwoofer cable to .1/LFE input (right one) and you have the .1/LFE Level knob (right one) at middle. Just to make sure you have looked the correct knob with correct input as there is one for each.

Crossover knob should be by-passed when connecting to LFE, 120hz (max) would be correct position for it. I would keep the power switch at Always On when you play test tones or if you run Audussey so the sub isn´t sleeping, Phase switch at 0.

Has anything changed otherwise changed some settings in your Denon recently etc? The sub is still working (barely) if you hear test tones produced by it.

Tzero_Rear.jpg
 
Providing you have checked the above and they are all correct. Does the sub turn on with an audible click? If not then it could be a simple relay failed. That's what happened with my T5, simple repair although it is likely to cost you an investigation fee. Ask in one of the dealers in Reading as they can more often than not put you in touch with a good repairer.
 
Providing you have checked the above and they are all correct. Does the sub turn on with an audible click? If not then it could be a simple relay failed. That's what happened with my T5, simple repair although it is likely to cost you an investigation fee. Ask in one of the dealers in Reading as they can more often than not put you in touch with a good repairer.
All of the settings are as above and connected to the LFE input. I just noticed the lack of bass in a movie I was watching and investigated from there.

It certainly doesn't have that noticeable click/slight bass boom sound when you power it on anymore. So you could be right? Hopefully it is also a simple fix. I had heard that if the sub makes a low noise it could be blown also?

When you say Dealers do you mean people like Richer Sounds? What is their repair service like? I was under the impression that Subs were a bit tricky to fix and you needed a REL approved place.

Thanks for your help guys much appreciated.
 
All of the settings are as above and connected to the LFE input. I just noticed the lack of bass in a movie I was watching and investigated from there.

It certainly doesn't have that noticeable click/slight bass boom sound when you power it on anymore. So you could be right? Hopefully it is also a simple fix. I had heard that if the sub makes a low noise it could be blown also?

When you say Dealers do you mean people like Richer Sounds? What is their repair service like? I was under the impression that Subs were a bit tricky to fix and you needed a REL approved place.

Thanks for your help guys much appreciated.

You haven´t touched any settings on receiver which might have caused this? I ask because the sub still works and puts out some bass so just wondering..
 
Does the high level work?

Do you have another amp to test?

Have you checked the sub out is not switched off and its settings on the avr?

Have you got another subwoofer cable to try?
 
You haven´t touched any settings on receiver which might have caused this? I ask because the sub still works and puts out some bass so just wondering..
On the amp its set to LFE 120hz for the sub. I even tried main+120hz. I have also tried both channels on the amp for the sub. I basically have not touched settings on this for 4 years previously :). I went into the tone test and tried increasing the DB on the sub as well. It did get louder but only very very slightly (I had to put my hand on the speaker to make sure it was vibrating). You can hardly hear it and the bass does not sound right to be honest.
 
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Does the high level work?

Do you have another amp to test?

Have you checked the sub out is not switched off and its settings on the avr?

Have you got another subwoofer cable to try?
What is the high level? Is that the other input on the Sub I presume? How do I test this using my amp? What settings on the amp should I use if I plug into it?

I have a stereo amp...azur 640A. Probably can't use this can I?

The sub out is definitely not switched off as the tone test does generate some noise and the speaker vibrates....but so so quiet (you have concentrate to hear it). I tried increasing the DB in the tone test...it does get very slightly louder but you can still hardly hear it at all and the bass does not sound right.

No unfortunately I don't have another cable to try. I guess it could be the cable but I would be very surprised as it is a good quality one.
 
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The high level is the input via the neutrick connector, on the other end should be 3 wires, black, red and yellow. Any class ab amp will work.

The 640 will work.

It's surprising but not impossible as one of my not so cheap QED sub cables doesn't work.. Also check the plugs aren't loose on the ends of the cable.

Do you have access to another sub. If a different working sub is still quiet then the issue is likely to be before the sub.

Tried the other low level input?
 
Ahh yes I had forgot about the cable that came with it (neutrick connector). Think it is still in the box which is in loft. Shall have to dig it out and try it. How do I test the low level connector? What settings on the Denon AMP?
 
For testing purposes, any setting as long as it's outputting a signal below the crossover frequency set on the sub.

Trying the high level will rule out the driver and the amp section.

It's a process of elimination.
 
For testing purposes, any setting as long as it's outputting a signal below the crossover frequency set on the sub.

Trying the high level will rule out the driver and the amp section.

It's a process of elimination.
Ok thanks...can you tell me what the difference is between the LFE and low level inputs? I was just told to use the LFE input and don't really know the benefits or reasons why.
 
As far as I can tell there is no difference, they're both low level phono input.

I have an older Rel sub which allows two low level and the high level connected at the same time and it will switch the input automatically.
 
As far as I can tell there is no difference, they're both low level phono input.

I have an older Rel sub which allows two low level and the high level connected at the same time and it will switch the input automatically.
I have found the neutrick cable...I am a little bit thrown by the 3 wires...red, black and yellow. What is the yellow for? Where should I connect them on my Denon Amp (if possible)? Will the Amp know the sub woofer is connected this way instead of using one of the two sub woofer phono inputs?
 
The red, black and yellow will take neglible power from the channels. Your amp won't know and won't need to know.

For the purpose of testing the driver and amp, you can set the avr to 2 channel mode then play anything with bass or low frequencies.
 
Here is how to connect
 

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Here is how to connect
Ok just to check (that I don't do anything stupid and potentially damage the amp) do I remove the current front left and right speakers and only attach the sub to these terminals alone? or do I wire it in along with the existing front speakers? I have some of those plugs...so assuming it is ok I was going to piggy back them into the existing plugs that are connected. Thanks
 
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Ok just to check (that I don't do anything stupid and potentially damage the amp) do I remove the current front left and right speakers and only attach the sub to these terminals alone? or do I wire it in along with the existing front speakers? I have some of those plugs...so assuming it is ok I was going to piggy back them into the existing plugs that are connected. Thanks
REL-Neutrik.jpg
 
But do I only connect the sub and remove the other speakers to these terminals? I obviously currently have 2 front speakers on these. Or is the sub just added as well.
With the high level connection on all REL and BK subs the connection is made alongside the speakers. I did it years ago but have not bothered since and just use LFE but we are trying to eliminate problems with the sub.

As you do have some movement of the driver then it could be an RCA lead problem. If you have a spare RCA cable then try that. If it's too short to reach between the amp and sub then just plug into the sub, turn it on and turn the volume up. Tap the other end of the cable, it should produce a boom. That's usually an indication that the sub is performing correctly.
 
With the high level connection on all REL and BK subs the connection is made alongside the speakers. I did it years ago but have not bothered since and just use LFE but we are trying to eliminate problems with the sub.

As you do have some movement of the driver then it could be an RCA lead problem. If you have a spare RCA cable then try that. If it's too short to reach between the amp and sub then just plug into the sub, turn it on and turn the volume up. Tap the other end of the cable, it should produce a boom. That's usually an indication that the sub is performing correctly.
So in summary I've tested the Sub with a two speaker setup and have connected via all the inputs available (including neutrick). I also found an old RCA cable and tried that in-case of a cable problem.

The results of my findings are that there is no real difference in bass sound between all of them. There is bass coming out of the Sub and for some rock tracks with a lot of bass you can definitely hear it. If I put my hand on the speaker you can feel it pumping in time to the bass drum (on some tracks) and it is working hard.

Here comes the but....

The bass does not seem powerful at all. I had to increase the volume of the AMP to 70% to really notice it. In actual fact I disconnected the front two speakers so I could just listen to the Sub at one stage (as they were kind of drowning it out).

I went back to the tone test and (noticed this time) there is almost a distorted/crackling sound with the bass tone test sound if you really concentrate on it. Best described as kind of soup boiling sound along with the bass rumble. Again when you increase the DB say from 2.5+ to 7.5+ the Sub hardly changes volume noticeably.

Any ideas? I would guess that it is partially blown somehow.

Ideally it would be great if I had another Sub I could test along side it.

Of course part of me is starting to think it has always been like this and I am going mad in lock down :)

Thanks for all your help and I am learning stuff which is great (even if my Sub is not A1).
 
Have you called to REL and ask can they connect you to their tech side people, then you could describe the issue to them and they would probably give some idea where it could be?! If too expensive to repair then have to consider something else, but you never know if REL would come forward and help with the costs or something so i would call them first!

REL Acoustics, Ltd.
North Road, Bridgend Industrial Estate, Bridgend CF313TP
e: [email protected] p: +44 (0) 1656 768777
 
It sounds like there is definitely a problem somewhere on the sub, either the amp plate or the driver.

There is a fb Rel group, which is regularly accessed by Rel, you can also ask for Ideas.
 
Have you called to REL and ask can they connect you to their tech side people, then you could describe the issue to them and they would probably give some idea where it could be?! If too expensive to repair then have to consider something else, but you never know if REL would come forward and help with the costs or something so i would call them first!

REL Acoustics, Ltd.
North Road, Bridgend Industrial Estate, Bridgend CF313TP
e: [email protected] p: +44 (0) 1656 768777
No not yet. I was actually going to complain to Richersounds first and see if they would offer to do anything about it. I think it was under guarantee for 3 years but I expect hi-fi equipment to last at least 5 years if looked after. Or I could complain to REL directly first? Which is the best approach based on experience here? I doubt anything would be done but worth a try I guess.
 
No not yet. I was actually going to complain to Richersounds first and see if they would offer to do anything about it. I think it was under guarantee for 3 years but I expect hi-fi equipment to last at least 5 years if looked after. Or I could complain to REL directly first? Which is the best approach based on experience here? I doubt anything would be done but worth a try I guess.

Try both! I would talk with REL first.
 

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