MFW-15 increasing price

[armaraas]

No, it wasn't really free, it was just to keep the wife from asking too many questions at the time...

There is a fair number of humming sub threads that have popped up recently over at AV123, so I'm not sure if there is something going on with them, or what. My last sub didn't do that, but it was a cheaper one that wasn't even grounded anyway, so who knows...

I'll try contacting them tomorrow. The common recommendation seems to be a ground loop isolator from radio shack, though some people have said they had to turn up their gain quite a bit once they connect the isolator...

 

[armaraas]

Are you sure you need an isolator? Did you already troubleshoot where the ground loop is coming from?

I'm not sure if I've done everything I should have yet...at the most basic level- with the sub plugged into an outlet, and one end of the sub cable plugged into the sub and the other not plugged into anything, there is no hum. However if I touch the other end of the sub cable it hums the same is it does when connected to the receiver. I've tried moving the sub to a different room and it still does it when I connect it to 'me'. I've tried surge protectors and power conditioner to no avail. I've had everything in the room turned off- tv, receiver, and pc, and it's still there, although it does get louder as I turn everything back on. I'm not sure what any of this tells, or what to try next? Oh, I've tried different power cords too...

 

[jvgillow]

If you have satellite or cable TV did you try the unplug-your-coax trick yet? That is the most common cause. The second most common cause is that your sub might be plugged into a different AC circuit than the rest of your equipment, and not all houses have decent grounding between circuits.

As you already guessed, the reason why the MFW is humming and your previous sub did not is because the MFW uses a 3-pin power plug. I've had the same sort of issues with gear from Axiom, SVS, and av123 so normally it is an "environment" thing and not a defective amp. That is why some people recommend testing with a cheater plug temporarily, because if the hum goes away you know the amp is fine.

 

[armaraas]

Thanks. I haven't tried the unplugging coax bit yet, I wasn't sure if it would pertain to me. We do not have satellite or a cable box, just regular old cable line that goes from the wall to the tv, but that's the tv downstairs. The sub is upstairs and the tv here is not connected to cable or an antenna.

I was thinking about trying to find a cheater plug tomorrow to see if that helps while I look for a better solutiion, I assume I can probably find one at Menards or Home Depot? I don't think I have one that I can think of. I may also try to go around the house and unplug everything I can to see if anything makes a difference.

 

[TheFactor]

Bah, got my MWF-15 today. DHL tried to deliver it a day early, so I spent 45 minutes waiting at their hub for the driver to get back so I could pick it up after the missed delivery, and instead he decided to hang around our neighborhood until my wife got home so he could make the delivery...

Darn persistent drivers...

It was packed well, looks nice, told my wife to grab Finding Nemo as we went upstairs to connect it up...powered it up and BUZZZZZZZZZZ......
As my wife asks, "what's that noise? why's it doing that?"
"No reason, don't worry, it was free anyway, go back to your own room..."

Anyway, if anyone has any recommendations for ground loop isolators, let me know. I was kind of thinking this one-
http://www.amazon.com/Xitel-GLI1-X1-Ground-Loop-Isolator/dp/B00023XDYA

In the meantime, it will sit here idley as the hum/buzz is louder than my music...

Sorry to hear that hope you can get that hum or buzz gone thats a bummer. I thought they were suppose to come with some kind of a fix with the sub because so many people are having the problem. What finish did ya get ? That sub will put out some nice base from What i've read and heard so hang in there and once you get that buzz figured out you'll have a nice sub

 

[jvgillow]

Even CVS or Walgreens should have cheater plugs.

 

[calnbs]

Bah, got my MWF-15 today. DHL tried to deliver it a day early, so I spent 45 minutes waiting at their hub for the driver to get back so I could pick it up after the missed delivery, and instead he decided to hang around our neighborhood until my wife got home so he could make the delivery...

Darn persistent drivers...

It was packed well, looks nice, told my wife to grab Finding Nemo as we went upstairs to connect it up...powered it up and BUZZZZZZZZZZ......
As my wife asks, "what's that noise? why's it doing that?"
"No reason, don't worry, it was free anyway, go back to your own room..."

Anyway, if anyone has any recommendations for ground loop isolators, let me know. I was kind of thinking this one-
http://www.amazon.com/Xitel-GLI1-X1-Ground-Loop-Isolator/dp/B00023XDYA

In the meantime, it will sit here idley as the hum/buzz is louder than my music...

Did you get to check this link out

http://75.126.14.199/showthread.php?t=33239

 

[mike c]

Did you get to check this link out

http://75.126.14.199/showthread.php?t=33239

he's already posted the exact same post you quoted to that thread.

 

[armaraas]

Yah, I did post over on the av123 forum too, decided I'd try to get feedback there too and see what other people are trying or getting to work the best.
I'm going to try to get a cheater plug to try tonight.
MLS did tell me to give him a call today, but being at work I'm not sure how feasible that will be. If I can get home early enough tonight I will try their support and see if they can help me narrow it down more.

 

[jcPanny]

Ground loop

Having a ground loop problem is pretty common. AH made this ground loop troubleshooting thread a sticky in their beginer forum:
http://forums.audioholics.com/forums/showthread.php?t=5667

 

[MinusTheBear]

Bah, got my MWF-15 today. DHL tried to deliver it a day early, so I spent 45 minutes waiting at their hub for the driver to get back so I could pick it up after the missed delivery, and instead he decided to hang around our neighborhood until my wife got home so he could make the delivery...

Darn persistent drivers...

It was packed well, looks nice, told my wife to grab Finding Nemo as we went upstairs to connect it up...powered it up and BUZZZZZZZZZZ......
As my wife asks, "what's that noise? why's it doing that?"
"No reason, don't worry, it was free anyway, go back to your own room..."

Anyway, if anyone has any recommendations for ground loop isolators, let me know. I was kind of thinking this one-
http://www.amazon.com/Xitel-GLI1-X1-Ground-Loop-Isolator/dp/B00023XDYA

In the meantime, it will sit here idley as the hum/buzz is louder than my music...

Lots of MWF-15 owners are having problems with ground loops with this subwoofer. If you go to the av123 Loudspeakers and Subwoofer forum on their message boards there are plenty of threads and even a sticky on solutions to the ground loop problem.

 

[Gimpy Ric]

I'm sorry for the MFW-15 owners who have the hum. AV123 might have a design flaw in their amp. If a simple "cheater plug" won't fix the problem, then I would get an RMA and shop elsewhere.

 

[jamie2112]

It sound like You should buy another sub, might want to go with a different company. The hum is really a bummer. If I bought a sub and it hummed, I would not post on a forum, I would send it back ASAP. Opinions won't get you a new sub......

 

[MinusTheBear]

The av123 forums are flooded with MFW-15 "hum issues". I have been lurking there lately and that board seems to be out of control and not in a good way.

 

[TheFactor]

The av123 forums are flooded with MFW-15 "hum issues". I have been lurking there lately and that board seems to be out of control and not in a good way.

I have been checking out the Forum for the last few days and posted some stickys a few posts back on this thread to try and warn some of us but I was to late for him : ( but hopefully if he cant get it fixed he wont get stuck with a 260 dollars worth of shipping costs returning it .

 

[jvgillow]

Mark Seaton and Mark Schifter posted some comments about ground loops in the AV123 subwoofer thread on avsforum.

 

[mike c]

let's wait for him to use a cheater plug before concluding the sub is the problem.

 

[TheFactor]

But What I dont understand is why is almost everyone lately having the same problem if its not the sub and most are saying they didnt have it with there old sub Why are they still sending the subs out this way when they should be a plug and play sub not trial and error. When you buy a new sub or anything for your HT setup you shouldnt be expected to go out and buy something to make it wright, it should be that way from the beginning.If you are selling something with a known problem wouldnt the wright thing to do is advice your customer this is what your going to have to do to make work without a buz or hum instead of letting these folks buy it and get it home all excited and buzzzzzzzzzzzzzzzzz. They should disclose this problem on there website or make it wright before they send it out. Im sorry for the ranting but the more I read about it the more upset I get. I guess I better shut up before I step on the wrong toes. My apologies .........

 

[TheFactor]

Mark Seaton and Mark Schifter posted some comments about ground loops in the AV123 subwoofer thread on avsforum.

My 200 dollar veledyne dosent buzz, my 100 element sub didnt buzz, my first 90 dollar sony sub didnt buzz, and this 6oo or 7oo dollar sub from av123 shouldnt buzz and they should have the corrected ground loop or problem solver already on the sub before its sold, This wasnt directed towards you more towards there statement of how "you" or the proud owner can correct the problem

 

[mazersteven]

I guess I better shut up before I step on the wrong toes. My apologies .........