Axiom Home Page Forums General Discussion Technical Questions Axiom LFR DSP+ADA1000 amp random noise problem

Out of the blue, my LFR1100 speaker are making a loud hissing banging nose for 10-30min on there own. The Anthem pre-amp is turned off and there is no source feeding the DSP anything. It just out of the blue starts to make a real racket that lasts for about 10-30 minutes then goes away.

I thought it was the Sub Woofers that were having an issue as about 3 weeks ago I heard this owful racket but had no clue where it was coming from. by the time I got downstairs into the media room and got to the speakers the problem went away. So I put it up to fluke. Then it happened again the following week so I just turned off the power to the Subs as I have not yet got around to running the photo 3.5mm 12v power lead around the room. Then this afternoon it happened again. it clearly is the DSP I think as that was the first thing I turned off and the noise went immediately away, so chances of it being a defect in the amp is slim.

They are about 2 years old so I imagine that the speakers and dsp are still under warranty. What should I expect from Axiom to get this fixed?

Turn the DSP off, unplug it and then turn it back on. Leave it like that for 24 hours. If the demons are still in it after that, Axiom will likely ask you to send it back for factory exorcising.

I ended up calling Axiom and Deb was none the wiser on what to suggest. She has said that Andrew will be getting in contact with me. The speakers are still burting into noise, so I just have to leave them turned off all the time now when not in use and remember to turn the DSP back on as there is not any 12v switch for the unit.

RF? Radar signal from a local airport? ELF naval broadcasts? Alien encrypted communications?

Well. It turns out that Axiom doesn't have a clue as to why this randomly happens. The only suggestion that I got was to disconnect the pre-amp from the DSP and see if the problem persists.

BUT as this is a random occurance that has happened 3 times in a 2 month time span, I fail to see what this is going to tell me, other than trying to watch TV or a movie with my front speakers disconnected really sucks.

The problem has so far only occured when the pre-amp is turned off. I figure that I just have to get my 12v trigger hooked up so i can just turn off the AMP. While i am at it, I think i will get a 12v triggered relay so I can turn on/off a set of power outlets so my DSP along with the two Amp One/A can get powered on and off with the trigger as well.

Guess Andrew taking so long and giving me nothing to work with to figure out what is causing the issue made my decision not to upgrade to a bigger ADA amp easy. If Axiom is not serious about supprting their customers, then little reason to support them buying new stuff.

Random events are very difficult to troubleshoot. They are by nature transient and unpredictable. Try another DSP, see if it cures the problem. Since everything in the signal path after the source is Axiom made, I expect you will get the help you need from Axiom.

Matt,

What Andrew asked you to try in the PM he sent you was to disconnect the input cables from the pre-amp to the DSP, at the DSP, without turning the DSP off the next time you hear the noise. This will tell us if problem is upstream from the DSP or not. When you turn the pre-amp off it is actually only going into standby mode which is activating a muting circuit in the pre-amp. We just want to establish that this muting circuit is staying active.

Also, is the noise is coming from one, two, three, or all four channels of your LFRs?

I guess I was hoping that there was some "oh that is caused by xxx' moment. For me as it is a random occurrence that so far has only happened when I am not using the equipment with everything turned off apart from the DSP and the ADA amps (as I had not run the wire for 12v trigger).

The noise is very loud when it does happen, and at 3am it doesn't go down to well. I am going to guess as Andrew doesn't seem worried, it's not that my DSP is going to suddenly burst into flames and burn the house down, I can assume it's a random thing.

I gather if the amp is turned off then the speakers won't make any noise, and even iff the DSP is generating random noise it won't affect me, my speakers or my families happiness as the sound won't come out of the speakers.

I would suggest you work with Axiom to locate the problem. You are 2 years into your warranty which means if something is busted, you can get it fixed for free. That includes shipping both ways IMO because you paid a tidy sum for your Axiom gear.

Three years into my Audiobytes the amp developed a problem and I neglected it and now I have no one but myself to blame. Well, that's not quite true. I blame a certain individual with the initials of TC.

This. If you want 'don't give a damn', go talk to your local bank about, well, anything. If you want good customer service and a resolution, work with Axiom. This product is at least in part Andrew's baby. He cares.

The problem is harder than that. if it was failing or making the noise on a consistent basis then you have something to go on. Right now it has made this awful racket 3 times. Once at 3am and by the time it woke everyone up and I got downstairs and thought it was the subs, so went to turn them off and the deep rumbling sound stopped. OK. So l left them turned off.

About 5 days later it happened again when I was not home and my wife told me about it. said it lasted for about 15-20 minutes.

Then it happened when I was home about 3 weeks after and I turned off the DSP and the problem stopped.

Now, do I leave everything turned on and hope that it makes the noice when I am around and not sleeping in the hopes of figuring if I pull the leads from the preamp and it stopes that I now have to deal with Anthem to see why the Preamp is doing this only for them to point the finger back at Axiom. Or just turn the unit off when I am not using it and solve the issue that way?

Sadly in the detail of your warranties that your probably better of using if possible. You'll probably need to show the wife how to disconnect them in order to help find out what the source of the problem is.

Mine especially dislikes dealing with the connections for fear of doing something wrong.

The thing is, this is now a defect but it may manifest itself into a failure in the future. Depending on what that failure is, you may be even more screwed than you are now. For all you know, whatever is going bad, may take out whatever is good with it!

It's a crappy situation. I've learned to buy only what I need, test the shit out of everything I buy and trust my instincts about what I keep and what I don't. In fact, I barely buy anything anymore because I am continuously disappointed and don't want to spend my time testing for others.

Mat, are you stating above that when you heard this noise and turned off your subs, the rumbling sound stopped? If so this has nothing to do with the DSP as I am assuming your subs are driven directly from line level sub outputs on your Anthem. If that's not the case and you are insistent that the DSP is the issue, get in touch with Debbie to send it in and I'll replace the internal parts. The reason we have asked to have the Anthem removed from the equation is that when you turned off the DSP and the noise stopped it could simply have been due to no longer feeding the pre-amp signal to the DSP. The DSP has muting circuitry which grounds the outputs when turned off, shorting the inputs to the amplifier channels. One thing everyone needs to remember is that Axiom stands behind their products more than pretty much any audio manufacturer out there. If you have a problem in the future, even if something is out of warranty it usually ends up being repaired for little to no cost.

Thanks,

Andrew

Insert "like" button here

Andrew. you didn't read the whole post.

The problem IS NOT CONSTANT.

On the first time I heard the noise, I thought it was the SUB. It was just coincidence that when I walked over to the subs and turned them off that the sound stopped. The subs are NOT TURNED ON, but yet the problem has persisted two other times. The sub woofers are sitting right beside the LFR speakers so it would make sense that it would be impossible to know if the sound was coming from the subs or the LFR's unless to put your ear right beside the speaker.

The Anthem Pre-Amp gets turned off after I finish listening. I guess like every piece of equipment now, it goes into standby and not really turned off. The noise has only happened 3 times, and only from the LFR speakers, and not from the other center and surrounds. Those also have a powered amplifier hooked up to them that was turned on.


If I had my ADA1000 amps hooked up to the 12v trigger so they would turn off when the Anthem Pre-Amp was turned off, thne I would never have known about this issue. It was purely that they were left on. I have since done this.


I have no idea as to what is causing the issue to happen. If Axiom tells me that it is nothing to worry about and by simply having the Amps turned off that all will be good, then I will happily take that as a solution. If you really feel that I need to leave the amps turned on with the DSP so that I can try and get the event to happen again ( and have ZERO worries that this noise could damage the speakers or reduce their life expentancy) then I will comply to see if the issue can be further isolated. I am not always in the house so there most likely be times that it could be acting up but I am not there to hear it.

My goal in life is to be happy and enjoy.

I will gladly phone back in the week after thanksgiving and discuss what you would like me to try.

This is why I bought Axiom. I do really like their ADA amps and they have been rock solid and have had no problems where other equipment seems to be finicky.

With the amps auto turning off, the speakers don't make more noise. For me this a liveable solution especially given the statement Andrew made above about the commitment of Axiom in the future. If the unit konks out somewhere in the future, if it can be repaired for a reasonable price then what else could be asked for.

Ok. it was just a matter of waiting time. I left the DSP and the Amps turned on, and after a week of waiting, I managed to get it acting up when i was inside the house. Actually, i had just got home from some shopping and heard a static crackling noise from the basement.

As Andrew asked, I pulled the middle two RCA inter-connects from the Pre-Amp to the DSP and the noise continued on/off for about a minute. I then turned off the DSP and the sound stopped right away. The ADA1000 amps were left turned on so I know it wasn't being generated by them.

So the DSP is acting up. I guess I will need to send it into Axiom to get them to take a looksy at them.

Good to hear you caught it in the act.

I was going to add a comment about how waiting a week would have been good practice for hunting, but then I remembered it's only real hunting practice if you sit outside in the rain all week.

I highly recommend Axiom has a look-see.

What, no house calls?

I have no problem in shipping the DSP up to them. I can run the speakers with just the fronts (sans dsp).

It is an interesting poser. As there are simply just too many variables to really point the finger at the cause of the problem. All we can really do is eliminate the likely causes and see what falls out in the process. I know I am in good hands and Andrew is onboard to trying to figure out what is causing this. I'm in good hands as they say.

Why not just turn the dsp off?
I cant imagine a benefit to leaving my system power up while I'm not I'd using it.

The DSP doesn't have a 12v trigger so if you are turning it off, then you have to remember to turn it back on. With the rocker power switch at the back of the unit that is a bit of a bugger when it's mounted on a rack.

I am shipping the unit back to Axiom hopefully today, but I might wait until Monday so it's not sitting in a Fedex warehouse over the weekend.

The issue with the DSP has gotten worse, as I was watching NetFlix yesterday and the crackle/buzz sound started happening during normal listening, so I think it's an actual failure inside the unit. That actually is good news as if you can get it doing the problem most of the time it's far easier to diagnose and fix. Also helps to point to where the issue is coming from.

Huh
I assumed there would be a trigger

A trigger isn't needed because the DSP consumes very little power in standby.

FWIW, last week I heard a noticeable but not very loud somewhat rhythmic noise coming from somewhere in my system after turning it off. It lasted for no more than a minute then went away on its own. I had been playing music fairly loud and for a good few hours before this, but the noise was neither loud enough nor lasted long enough after shutdown that I was motivated to investigate further, so I can't say whether it was only coming from my LFRs or also other speakers. However, given that the DSP is the only component that doesn't automatically power off, they are an obvious suspect.

Perhaps this is an annual Halloween Easter Egg that Ian and Andrew built into the DSP?

It could have been your ADA.

I have just got my DSP back on Friday. I will see if the issue has been fixed and hopefully Andrew has left some notes about what he found inside the box.