Weird sound from sub; is this normal?

[corysmith01]

So I just moved about 2 weeks ago to my new, much smaller apartment in New York. I finally got everything set up in my living room in terms of equipment. Today I was playing with it, listening to cd's, poistioning and repositioning speakers just to tweak and see what works best in my new, much smaller room. In doing so, I was down on the floor adjusting my right speaker and noticed a weird sound coming from the area of my subwoofer. It's in the corner of the room near the right speaker. I put my head closer and closer and though that it might actually be coming from the subwoofer. I put my head right next to the driver (this is a Velodyne SPL800II) and sure enough, it was. It's like a very low, rumble-like sound...more like "wind" I guess. Imagine if you were trying to create a wind-like sound to foley into a movie...well this just might work. I did some experimenting to see if I could figure out what's going on.

First, off, I've found that it does not do this if there is no signal being fed. If it's just on, but I haven't pushed play on a CD/DVD yet, nothing. But, as soon as a signal is fed to it, the "wind/rumble" kicks in. Also, if I push stop or pause, or even turn off my receiver and dvd/cd player, the sound continues. So, it's only once a signal has been received by the sub.

Next, I tried unplugging it and plugging it into another outlet. This did nothing. Same sound.

Next, I went into my speaker set up and tried noodling there. I originally had my sub at +6db so that it kicks on more easily (i'm a small apartment so I can't get the sound cranking to make it auto-on). I flattened it, putting it back to 0db. No change. The sound is still there.

Now, my question is, is this normal? Do subs and their low frequency tendencies just emit this sort of sound when in use? In my previous apt., I was so far away from my sub cause the room was huge that I may have just never noticed it...that maybe it was there all along. Again, you have to get pretty close to it to notice it. It's not like I can hear it when I'm sitting on my couch. I had my head inches from the driver in order to hear it. Is this normal or is something screwy going on with my sub?

 

[fergusonv]

No, that is not a normal sound. I would try swaping cables first. If that does not remedy the problem it may be a driver or amp problem. I assume it is making this noise at low volumes?

 

[corysmith01]

Unfortunately, I don't have another sub cable lying around. I'll have to order one from Blue Jeans or Impact. In the meantime, while I wait for another cable to come in the mail, should I avoid using the sub? Or, is there anything I overlooked that I could check. This is very perplexing. The sube is virtually brand new...I just bought it in November/December.

 

[Sheep]

Unfortunately, I don't have another sub cable lying around. I'll have to order one from Blue Jeans or Impact. In the meantime, while I wait for another cable to come in the mail, should I avoid using the sub? Or, is there anything I overlooked that I could check. This is very perplexing. The sube is virtually brand new...I just bought it in November/December.

Not even a coax, basical analog audio or video cable?

Go through all the equipment you have, tunr them on and off, unplugging and such and see if you cna locate the source of the provlem.

SheepStar

 

[corysmith01]

corysmith01=bonehead.
Thanks Sheep...I didn't even think that I could use really any analog cable. I ran some cheap-o red/white analogs to it (just one side obviously). Got the same noise. So, after hitting stop on the cd, I powered down the dvd player. Sound remained. I then powered down my receiver. Sound remained. So, the only thing left connecting this sub in anyway was the cable. So, with the sound still coming from it, I pulled the rca connector out of the back of the sub. And you know what, the sound is still there. I just walked back over to it. The only thing it's connected to is the wall socket providing it power...no connections to the equipment whatsoever, and it still sounds like it's a wind tunnel...a slight rumbling, wind-like sound is still there. How crazy is that? I'm guessing this is not good.

 

[Buckeyefan 1]

Cory,

You say you have a small apartment. There may be interference in the lines - you could be on a shared circuit. Does your apartment have its own breaker?

If so, unplug your cable box, refridgerator, and turn off any lighting (especially those with dimmers). Plug the sub back in. Does it still rumble?

If it does, and you can only hear this sound from less than a few feet away, it's probably nothing to worry about. If the sub is still under warranty, Velo may swap amps with you if it's causing loss of sleep. We can't have that!

 

[corysmith01]

Thanks buck. I'll try that...It'll take me a minute. I don't know if it has it's own breaker or not...it is smaller and older, kinda cramped together. Welcome to New York, right? I'll report back.

And no, we can't have loss of sleep. I've already written to Velo, just to let 'em know what's going on. I'm still waiting to hear back.

 

[corysmith01]

Alright...no dice. Unplugged the fridge (that was a pain in the rear.) Turned off all lights...none have dimmers. Unplugged cable box. Played 15 seconds of a song, heard the sub auto-on. Stopped the song and listend. Wind tunnel. Unplugged the rca, again leaving the sub completely unattached to anything other than the outlet, and was still making that sound. I give up. WTF?

 

[A/VUSMCSGT]

http://www.axiomaudio.com/tips_eliminate_hum.html

I think this link might help you out. I didn't read the whole thing, but it might.

Let us know if it does.

Joe

 

[Sheep]

http://www.axiomaudio.com/tips_eliminate_hum.html

I think this link might help you out. I didn't read the whole thing, but it might.

Let us know if it does.

Joe

This is not a "hum" its wind noise.... that doesn't sound right..

SheepStar

 

[corysmith01]

I may be not defining it properly, but I read that passage and I think that mine isn't a hum. It doesn't sound like a "hum" unless what their definition of hum differs from mine. Mine is more of a wind-like sound. It's very similar to your receiver set up when you send pink noise to each speaker for level setting. It sounds kinda like that.

At any rate, mine was already plugged into the wall like they prescribed. That didn't work. I can't reverse the prong as the outlet won't allow it. I did, just for the heck of it, plug it into my receiver to see if that changed anything. Nada. Same noise.

I'm perplexed...and a little annoyed.

 

[corysmith01]

Just a follow up to let anyone who may be interested know what's going on...and also to seek some confirmation.

I got an e-mail back from Velodyne. Very nice. They responded very promptly, so kudos to them. However, I just want to make sure that I'm not over-reacticting to a sound that "may" be typical of my sub and its amp. The reason I say that is becuase, a portion of Velodyne's response said this:

If there's a problem it can be corrected and we can also update your amplifier as required. It is not unusual for the switching amplifiers to have some low level background noise, but that is typically only heard right in front of the driver at very close distances. If it's audible beyond that or over the music then it sounds like something else.

So, could it be me just jumping the gun here? Meaning, is this noise "typical" and I just never noticed it due to my much larger room prior? I've attached a photo to show my 2 normal sitting positions. I pulled out a tape measure and measured positions. The chair off to the right, as noted, is about 5.5 feet from the sub when you're seated there, and I can hear it pretty clearly from there. Where I'm sitting on the couch, to take the pic, the noise is barely audible, but there nonetheless. So in the chair position, the sub is actually just off to my right, albeit 5 feet away, but would that be considered "right in front of the driver" or should this be fine?

And finally, I've also noticed that it now makes an audible "click" when it shuts off/goes into standby. I have it on auto-on, so if it sits there for a few minutes, like most subs with auto-on, it goes into standby mode. Well, when this happens, I can actually hear it do so. It's not a loud click by any means, but it is definitely evident that it has gone into standby mode.

I'm hoping that there isn't anything wrong, but I'm suspecting there is as this just doesn't sound right. In the e-mail, they said it may be necessary for me to mail the amp to them. That sucks. Number one, I have no experience taking those plate amps off (not that I suspect it's all that hard) and two, that means I'll be without a sub for who knows how long. Uggh.