MFW'S Amp buzzing, help!

[sbisheff]

I didn't really know where else to put this so I figured this was a good a place as any* :D. I also put this on AC in Danny's circle as there are a lot of ex AV123-ers there too.

I've got two MFW's with first gen amps that have worked perfectly for probably 3-4 years I'm guessing. I got them brand new A stock. Last night one of them started buzzing. I turned it off and it stopped and it was late so I didn't bother researching the problem. I just got a chance and tried unhooking the RCA and it still buzzed. I then removed it from the power strip it was plugged into and plugged it straight into the wall, still buzzing. Unplugged the RCA while it was directly plugged into the wall, still buzzed. For grins I plugged it into a ground lift plug and straight into the wall, still buzzed and removed the RCA and still a buzz.

Basically I'm assuming I've now got a dead amp correct? It is still producing sound when turned on but there is that constant buzzing. It isn't crazy loud but loud enough where I might turn into a crazy person if I kept it on.

Thoughts? Possibly some bad capacitors that could be replaced?

Thanks!

Scott

[tesseract]

Good isolation methods to troubleshoot, but it only confirms what you already suspected, caps are gonzo.

I would leave it alone until you can get the caps replaced so as not to take out any other components, you don't want a catastrophic failure!

Once you do get them replaced, keep in mind that repeated turn on/turn off cycles expedite cap failure. Just leave the amps on 24/7.

[sbisheff]

Good isolation methods to troubleshoot, but it only confirms what you already suspected, caps are gonzo.

I would leave it alone until you can get the caps replaced so as not to take out any other components, you don't want a catastrophic failure!

Once you do get them replaced, keep in mind that repeated turn on/turn off cycles expedite cap failure. Just leave the amps on 24/7.

Somehow I figured you'd chime in here :) I'm gonna try and replace the caps I think. I can probably manage it. It's such a common problem I knew I'd be able to get help!!

Thanks.

Scott

[tesseract]

Somehow I figured you'd chime in here :)

Yeah, I've seen this happen about a zillion times. :D I sent an original V1 amp, NIB OEM driver and offers of tech support with my MFW-15 when I sold it, along with full disclosure of the collective history of amp failures... just in case. Still, I expect the driver's life to far exceed the amps'.

I know you have been enjoying these puppies for years, you got a good run out of them. No reason you shouldn't get a few more years, they are good sounding subs.

[sbisheff]

Yeah, I've seen this happen about a zillion times. :D I sent an original V1 amp, NIB OEM driver and offers of tech support with my MFW-15 when I sold it, along with full disclosure of the collective history of amp failures... just in case. Still, I expect the driver's life to far exceed the amps'.

I know you have been enjoying these puppies for years, you got a good run out of them. No reason you shouldn't get a few more years, they are good sounding subs.

Exactly! They are good outdoing subs and were really my first "real" subs. I definitely can't complain about the life I've gotten rom them knowing the history. I will definitely do the cap fix, seems like it should be pretty easy.

Scott

[boober]

That buzzing sound your amp is making is the amp begging for you to put it out if it's misery!!!! :biglaugh:

[dbeng]

Hi skeeter,

There is a well documented capacitor fix that many people have had success with. Murrel Gray has been extremely helpful to all owners of MFW 15s and has helped to get many up & running.

His number is on the attached link, give him a shout to discuss the options you have to fix your amp. For a while he was selling the V3 amps, but they are now sold out, but I'm sure he will do what he can to help.

https://simplysoundaudio.com/MFW-15_INFO.html

Good luck with the repair.

Dan.

[sbisheff]

Hi skeeter,

There is a well documented capacitor fix that many people have had success with. Murrel Gray has been extremely helpful to all owners of MFW 15s and has helped to get many up & running.

His number is on the attached link, give him a shout to discuss the options you have to fix your amp. For a while he was selling the V3 amps, but they are now sold out, but I'm sure he will do what he can to help.

https://simplysoundaudio.com/MFW-15_INFO.html

Good luck with the repair.

Dan.

Great thanks for the link! I knew Murrel had done it but didn't know where to find the info. Its MUCH appreciated! I'm going to do the fix this weekend. Wife and half the kids are gonna be out of town so I'll have plenty of time to tinker :applause:

Scott

[a-rone]

Scott this doesn't give me much hope for my mfw-15. :( I think mine was # 6 or 7 off the production line. It still sounds great and shakes the house when called to do so. Hope I don't have anything like this happen any time soon. I do have a version 2 amp in a box that needs the caps swapped out for when the version 1 amp in my sub finally bites the dust. I may just not fix it at all if that happens and pull the driver and make a lilmike's F-20.

[Sandbagger]

The cap fix generally will fix a ver1 or ver2 from my experiences, although there are not a large percentage of v1's that fail unlike a very very very high percentage of the V2's.....

And Turbos will be shipping I hope soon first large batch of drivers are being built now so we are talking a few weeks not months since I changed manufacturers for the drivers :applause:

Scott this doesn't give me much hope for my mfw-15. :( I think mine was # 6 or 7 off the production line. It still sounds great and shakes the house when called to do so. Hope I don't have anything like this happen any time soon. I do have a version 2 amp in a box that needs the caps swapped out for when the version 1 amp in my sub finally bites the dust. I may just not fix it at all if that happens and pull the driver and make a lilmike's F-20.

[sbisheff]

Aaron,

Mine were some of the later V1's so I'm sure you will be fine :applause:

Scott

[sbisheff]

The cap fix generally will fix a ver1 or ver2 from my experiences, although there are not a large percentage of v1's that fail unlike a very very very high percentage of the V2's.....

And Turbos will be shipping I hope soon first large batch of drivers are being built now so we are talking a few weeks not months since I changed manufacturers for the drivers :applause:

Nice Kevin! How much are the turbo upgrades?

[woofersus]

The cap fix generally will fix a ver1 or ver2 from my experiences, although there are not a large percentage of v1's that fail unlike a very very very high percentage of the V2's.....

And Turbos will be shipping I hope soon first large batch of drivers are being built now so we are talking a few weeks not months since I changed manufacturers for the drivers :applause:

Nice to know there may be an easy upgrade path someday when mine finally dies. :applause:

I think I may have gotten a little bit lucky. I had two v1 amp failures from the time I received my mfw in october 2008 through around March of 2009. (still sitting in my basement if those are useful for something) Then I had to wait until late July as they redesigned the amps for v2. That very first (small) batch of v2 amps, built by a new "better" supplier have seemed to do fairly well, while the later batches seemed to be much worse than the v1 failure rate. I don't know if it's my imagination or if there really were better quality parts in that first batch. Either way, after waiting 6 months to get the sub, then having it not working for all but about 6 weeks of the first year I had it, it's been completely trouble free for nearly 3 years. I assume it will die eventually, but here's hoping it takes a while longer.

[jjar]

I picked up a NIB MFW in June 2008 from the classifieds. It has performed flawless with the exception of a ground loop hum. It's not that bad so I have lived with it. How do I know what version amp I have?
Thanks.

[jjar]

I picked up a NIB MFW in June 2008 from the classifieds. It has performed flawless with the exception of a ground loop hum. It's not that bad so I have lived with it. How do I know what version amp I have?
Thanks.

Bump...can anyone answer this?
Thanks.