NEW MFW-15 amps (May 2010) *pics* - Page 80

Hi Murrel,

I have MFW15 which has now serious humming issue. It has been there for quiet a long time but now its getting louder and louder. I would like to know how to fix it. Please let me know.

I use my MFW15 very sparingly - so I don't know if matter at all for longevity for the mfw-15 woofer though.

Thanks.

See post 2361 for the hum fix.


Murrel

Installed 2 turbo kits in about an hour over the weekend.

Installation was very simple with no help. First one took about 35 minutes and the second about 25 minutes. Unscrew the wood face plate in front of the woofer, unscrew the 2 plates on the back, cut the wires, then unscrew the woofer. Mine both just fell out when the screws came out. Turn the box upside down (woofer hole facing up), place the self-sticking foam gasket around the hole, place the new woofer on the box (don't drop it in the hole yet), run the wire from the woofer through the small wire hole and plug the hole, then drop the woofer in the hole (making sure not to use the same holes from the old screws), screw in the woofer, turn the box back upright and put the self-sticking foam around the top and bottom plate holes, screw in the top plate, connect the wires to the bottom plate (no soldering needed-spade plugs attached so just plug em in) and screw the bottom plate. Connect to the amp and it's ready to go.

Did 2 things different from the instructions. First was to install the two rear plates after putting the woofer in instead of before. Doubt that makes any difference but did it to avoid damaging the connectors on the lower plate when the cabinet is flipped upside down to install the woofer. This also allowed me to pull the speaker wire tight so it wouldn't flap around inside the box (not sure this is actually needed as there wasn't much slack there anyway). Second, I used the original screws for the rear plates instead of the new screws supplied with the kits. Hopefully, these will do just fine, if not, it is a simple matter to use the new screws.

Disclaimer: I have China made rosewood cabinets from (I believe) the very first batch so YMMV. Everything fit perfectly with these cabinets so it was basically a drop right in, plug and play installation. The bolts for the front wood face plate used a metric hex, the rear plate screws were torx, and woofer screws were phillips. Be careful not to over tighten, the China cabinet uses an extremely soft material (wouldn't even call it wood).

Sound and feel was as others have described for the turbo kit and does not disappoint. Don't have any measuring instruments so I'll leave the numbers to others. But at one point, I had to turn it down for fear that the neighbors would think we were having an earthquake. Very happy with the turbos and glad that there's no more worrying when the next amp will fail. Had 3 amps fail since I bought them.

I am in need of a working amp, prefer a V3. Send me a PM if you have one for sale.

I am also looking for a working drop-in amp for the MFW-15. Please PM me if you have one available. Thanks!

Looking for someone to take my MFW-15 subs off my hands in the NYC Staten Island area preferred, My daughter is starting to crawl around, so i am making space, definitely not making any money.
2x MFW-15 Moho Satin w v2 amps installed, and 2x spare v1 subs. $250 total for everything picked up from me. Picked Up Only! Thanks. PM me only if you can pickup, do not ask me to ship. Comes out to $125 per sub, with spare amplifier, pics in the classified section.

PM sent

Kevin/Sandbagger has more Turbo kits being readied to ship out in the next few weeks, so I'd expect to see some more amps and drivers pop up soon after.

I have a v2.1 with a constant buzz as soon as I turn it on, with no source connected and the ground removed from my plug. I had a blown cap and replaced all 4 caps as suggested.

I am confident I did a poor job de-soldering and re-soldering and thus I also used the extra wire as per the suggestion as well.

It still hums. When I add the LFE source you can hear sound, but it is very low power, covered in hum.

When I removed the board from the plate there were 3 screws. It's obvious where the two on the edges go, but the one that goes through the plastic part located at D4.. There is nothing for the screw threads to grab there anymore. Am I missing something? Is this critical to the functionality of the sub?

Anyone have any advice to offer? Do I just buy a replacement amp? I'd love to fix this one.


Also, reading through these threads - HUGE kudos to Murrel. It appears you are a Prince among men.

Do you still have them.

Sent from my SCH-I535 using Tapatalk 2

My mfw-15 is one of the first 5 or 6 original subs off the line and is still running strong. I may have an oppritunity to pick up another mfw-15 that is missing the amp altogether. I have a vs 2 amp sitting in a box read to go that I can throw in it easy enough. Would paying a little less than $100 for the mfw-15 box and driver be worth the investment? Also has anyone tried doing their own version of sandbaggers turbo with say Dayton Audio RSS390HO-4 15" Reference HO and an external amp?

$100 for both is a pretty good deal.

The HO does pretty well with the same to little more power but if your gonna feed it like 1000W IMO a better driver would benefit you. From memory the HO gets pretty close to x-max with 500W in ~3.0ft^3 tuned to ~19Hz(approx specs of MFW15).

I can't model on this PC but I like the Behringer DSP amps for what they are and one channel of the NU3000DSP with the 15HO in that cab should be a good pair if the HO works ok on 620WRMS. That leaves the other channel to run your original. You could recoup some of the cost by selling the original drivers. So really not that much money for a big upgrade.

Get someone to model the HO in the MFW enclosure and see how much power it will take, I can't remember exactly. Assuming it works well on 620WRMS.......

Cost figures:

Buy additional Cabinet $100.00

Sell two original drivers ~$80 each for +$160

2Dayton HO15s 2X $149= $300-$160(from original drivers)= $140

Behringer NU3000DSP= $350

Total= (100)+(140)+(350)= $590

I'd ask MCCA about output comparos but two subs should have a smoother response capability over one especially since the Behringer has PEQ.

My MFW15 amp crap out within a few months after the replacing the capacitors. Looking for alternatives to bring it back to life. There are talks of others testing pro amps with the stock driver but didn't find anyone saying they use an external/pro with good results. Any suggestions for a used replacement amp, ~$150?

My MFW-15 started making some popping/crackling noises a few minutes ago...I assume that means it's on it's way out?

Might be able to save it for a while with replacing the caps

Turbo Kits are another option

... and I'm sure we'll see some more used parts available as more Turbo kits keep shipping out.

I replaced the caps I believe 1.5 years ago...how much manual configuration does the turbo option require to sound right after installation? I have never had a sub with an external amp.

I saw this post over at HTS so will post my reply here as well. Has anyone tried the Dayton SA230 external amp with a stock MFW? Only rated 230w into 4ohms but I wonder if it would be sufficient anyway. For under $200 there are not many options out there.

My V2 is still working fine but I plan on handing this sub over to my son shortly and inexpensive options to keep it going should he run into any problems with it in the future are always nice.

From what I understand, the SA1000 amp is internally modified to match the driver in the Turbo kit. There is a parametric EQ on the front of the amp which can be used to tune the sound to your taste, but for most applications isn't necessary. I would think setup would be similar to a plate amp integrated into a normal subwoofer, but with the added capabilities of the EQ if you find it necessary. I will know more this weekend as I am receiving a turbo kit for one of my MFW's that has a bad V2 amp.

Yes the SA1000 amp is customized for both frequency response for the custom driver I have made and also proper limiting. By getting the best possible response curve from the sub/amp system to start with out of the box just gives your other EQ processors a much better starting point to EQ your room vs having to EQ your sub and room.

Setup will be similar to higher end subs that have internal EQ and limiting. The PEQ is great for fixing the worst response in your room and then doing other EQ with either an outboard EQ or using the EQ in your processor.

Thanks for the feedback!

I'm a bit torn as I live in an apartment complex on the 2nd floor so am a bit hesitant to drop nearly a grand to fix this sub. I have to be think of my neighbors and won't be moving into a house for at least a few months, if not years...but I love the finish of the MFW-15 and its like a piece of furniture that I would hate to get rid of. I also don't feel like wasting time/money on used amps/drivers...decisions decisions!

From a very happy v1 Turbo owner (Cherry Rosa finish), I'd recommend doing the upgrade if you have the extra $$ available - just don't crank it up too often while still in the apartment...or invite the neighbors!

But once you do get into a house, you'll be VERY happy with the Turbo. I recently moved to a different house and have been slow to get the new media room where I want it, but my Turbo still impresses me whenever I do have time to pop in a movie. Next to my Kuro 141, the Turbo kit has been one of my best AV purchases...

Good luck!

I see that the fix in post 2361 is for V2 amps only. I believe that I I have V1 amp that developed a hum. Is cap replacement fix possible with V1 amps?

OOPs, let me add, what is the difference between version amps V1 & V2 and how do tell?

So I had a friend who is a much better solderer than I work on it and he fixed the buzz, however the sub is barely putting out now. I can barely hear it even turned all the way up (the gain and the receiver sub setting.)

Any ideas?

Here is wishing everyone a thumping 2013

Can anyone tell me the difference between version 1 & 2 of the defective amps?

And what about the fellow who was building /rebuilding the amps about a year ago????? Did he fall off the planet?

My V3 shows a green light but there is no signal.
Caps look good so does the fuse.
What else can I check ?

Looking for some direction here........ Member Sylc suggested removing the power plate so as to determine which model amp is being used in my model.

I removed the TORX screws and was very careful not to scratch the finish... No matter how I tried I could not remove that plate.... Is it glued on as well as screwed in? I figured by entering through the top plate, would be easier to see how the speaker wires are connected to the voice coil ( soldered = V1, Push-On's = V2)

Suggestions please ??????

Thanks for any and all assistance !!!!!!!

There was some sealing tape on mine. If you pull on the binding posts hard enough you should be able to break it free. Good luck!