NEW MFW-15 amps (May 2010) *pics* - Page 5 - AVS Forum
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post #121 of 2629 Old 05-23-2010, 09:25 PM
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Originally Posted by KERMIE View Post

I have no idea but is this standard procedure to release electronics to the public that has not yet been cleard for approval? We don't need the house to burn down at this point.

No, it's not SOP. The approvals are supposed to be in place before it's released to the public.

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post #122 of 2629 Old 05-23-2010, 10:27 PM
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Originally Posted by floridapoolboy View Post

If the new amp has an increase in power, why do users report that it is not as loud at a given gain setting as the old version?

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post #123 of 2629 Old 05-24-2010, 06:20 AM
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Originally Posted by ksteidle View Post

All,

This was sent to me by our Engineer today. Please call or email if you have any questions.

Kyle,

I have noticed on avs forum that there is a concern regarding the latest generation of amplifiers now shipping for the MFW-15.

This new amplifier is a further evolution from the design put into place some months back. This design is a more integrated solution. We developed this product from scratch rather than having to adapt a replacement board to an existing design as was done with the previous amplifiers. This has allowed us to offer both a more powerful and a more reliable product.



If this amplifier has more power, I'm both stronger and faster than I was when I was 21 (25 years ago). In both cases I can prove this is not true.

Quote:
This new generation of amplifier board is more powerful than the previous versions. The previous version, using the replacement amp board, produced approximately 400 watts at the rated distortion. This new amp produces approximately 500 watts at the same rated distortion (1%). The increased power can be attributed primarily to a larger mains transformer. The new transformer is a Toroid type which, besides being more efficient, produces less stray magnetic field than the older EI Core type.

Kyle, you're a good guy and I like you, but this engineer, since I don't know him I can say sorry Charlie, just cause you say it's so, don't make it so. My Dayton powered UFW-10 can easily keep up in output with my "new and improved v3 powered MFW". While I agree the amplifier section itself MAY BE more powerful, if the amplifier isn't getting the input (our maybe what I should say is preamp output voltage?) voltage to produce this power it could be a 10,000 watt amplifier section and it ain't going to do squat.

Quote:
The new pre-amp board is highly integrated and allows for flexibility in tailoring the equalization and features so it can be used in a family of products without redesign. The circuit boards do not look similar to the older design due to the exclusive use of surface mount components and sophisticated circuit layout. In addition to circuit design, consideration was also given to ease of manufacturing. This allows the design to be produced on an automated assembly process which produces higher quality, more reliable products.

Agreed to the point I could not see anything similar between the two and the circuits look better. While it may be better quality, I seriously doubt it is giving the amplifier the juice it needs to be more powerful or even equating the v2 version of the Chinese amp.

Hey guys, I'm a build it in America kind of guy! I LOVE that this is being produced and built in the USA. BUT, what I don't like, is being told this one is MORE powerful than the previous design and then getting the amplifier, installing it and then not getting anywhere NEAR the output of the v2 amp.

Remember, MLS made HUGE claims about the v2 amp, how it was PERFECTION. Well, in output it clearly delivered on the goods, reliability, well that's why we're here right, trying to get to the reliable part.

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I know that TADG has submitted this board for Agency Approvals that include CE, FCC and UL, but we will not screen the metal work to indicate this until all approvals are in house. Later units will reflect this, including the new av123 logotype.

Sigh, now let me get this right, I now have an amplifier that has had ZERO outside testing by any group or agency? I've heard great things about the amplifier company so I don't hold them responsible for this, they are building what they were told to build, I have no doubt about this. Once again the blame falls on the owner of AV123, TADG, WKRP, WLUP or whatever the hell he's calling himself these days. I thought TADG was many people, so which of the people that share this new ID are the one who sent this new amp for approvals and then released the amplifier to the public prior to at minimum FCC approval?? I would think anything being sold in the USA has to have FCC approval? Maybe I'm wrong.

I AM ON AMP NUMBER 7 counting this one, my wife considers these subs a running joke. Everytime she sees another white square box she calls me at work to make fun of them. So, thanks for the long brown box this time, I was saved from having to answer more questions about why I bother to continue to do any buisiness with AV123.

Quote:
The new amp is constructed in Colorado and will appear in many future products. We like the increase in power, but we also like the simple and very straightforward final execution of the design. Labor costs being what they are here, rather than The PRC, we feel that the design goals have been met or exceeded in every category.

I'm glad he is happy, I'm VERY disspointed, tell TADG, MLS the engineer that this amplifier DOES NOT have near the impact/output of the v2 design and I can prove it BUT I SHOULDN'T HAVE TO! You guys should know this!

I'm just a guy who likes HT, I wanted a reliable powerful subwoofer and bought the MFW because people (not just Craigsub) on MANY forums recommended it. When I put them in my HT I was blown over!

If I had received dual MFW's with the new v3 amplifier you would be getting them back, pure and simple. I can't begin to describe how disspointed I am. To have an engineer make claims that every single person who has the new versio amp can disprove, is appaling but then I don't know what information he was givin about the old amps.

I posted how I tested, if my testing was invalid IN ANYWAY please post it and explain to me where I was wrong and HOW AM I SUPPOSED TO GET THIS IMPROVED OUTPUT WHEN RUNNING THE AMP GAIN AT 100% AND THE AVR 10db HOT RESULTED IN 11DB LESS OUTPUT BUT HUGE DISTORTION?

In normal operation it was barely noticable if at all without cranking the gain to 100% and then upping the gain in the AVR. If these new amps are more powerful, explain to me how to properly set them up. Heck, maybe it's just me and I missed something?


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post #124 of 2629 Old 05-24-2010, 06:35 AM
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Originally Posted by Chu Gai View Post

Who is the engineer that designed the new amp?

And KH, I thought your earlier comment regarding the preamp section bore serious consideration.

With respect to the output power differences (400 vs 500), what were the input voltages for the two power ratings?

No idea, they have released nada about this new amp except to say the old one was 350va and the new one is 500va.

I guess you'd literally have to hear the difference between the two to understand how truely different they are. Old one you can feel the power, this new one is so soft. You can MAKE it make bass but who wants more distortion?

It's like I was driving a Mustang that I could prove did the quarter mile in 12 seconds flat at 118mph and the engine blew up and Ford secretly installed a new supposedly more powerful design and I took it to the track and the car ran 13.2 at 106mph and then I called Ford and they released a statement from an engineer that said they were happy with the design and it was going to be used across the board.

You can imagine how this would go right?

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post #125 of 2629 Old 05-24-2010, 08:46 AM
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Klipsch, you have summed up my feelings very well with your posts. I don't know why we are surprised, we expect changes from AV666 and WKRP (that was hilarious), and we get the same ol same ol. Shame on us for expecting new things from this company
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post #126 of 2629 Old 05-24-2010, 08:52 AM
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Someone should test both amps with a resistive load (or even better with the driver connected) and see if it really does have more power.
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post #127 of 2629 Old 05-24-2010, 08:52 AM
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Originally Posted by volta View Post

...I don't know why we are surprised, we expect changes from AV666 and WKRP (that was hilarious), and we get the same ol same ol. Shame on us for expecting new things from this company

Sounds a bit like Albert Einstein's definition of insanity...
"Insanity is doing the same thing over and over again and expecting different results. "

Wouldn't you say its about time to move on? ...sell the MFW and get something more reliable from a company that's going to be more reliable.

"For deep bass, the listener is not really listening to the speaker, but rather, is listening to the room as it is being played by the speaker."
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post #128 of 2629 Old 05-24-2010, 08:58 AM
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Originally Posted by monomer View Post

Sounds a bit like Albert Einstein's definition of insanity...
"Insanity is doing the same thing over and over again and expecting different results. "

Wouldn't you say its about time to move on? ...sell the MFW and get something more reliable from a company that's going to be more reliable.


I have moved on, in that I won't be buying any subs from them anymore. I am actually waiting for the Seaton/Motor City MFW upgrade. I think that will make the MFW bump again the way it should have from the beginning.
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post #129 of 2629 Old 05-24-2010, 09:01 AM
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Anyone called and discussed it with them this morning?

Also, I have a V3amp and I plan on doing some testing of my own this week. I should be able to do direct compaisons as well since I have more than one unit to complare.

I'm really interested in level matching the surround speakers 10db low so that I can get enough line level signal to keep the gain on the sub at a normal position and still have some gain leftover on the controller. I normally listen to my system at -18 which is ample volume with peaks >100db. I have several different memory presets so this will be easy enough.

Any of you guys who already installed the amps try this?

Don't waste time reading signatures.....
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post #130 of 2629 Old 05-24-2010, 09:29 AM
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Originally Posted by ksteidle View Post

All,

I know that TADG has submitted...

ROTFLMAO!

TADG - that sure adds credibility to the post.

This company is shameless, but kudos to them for fighting and lying to the end.

"Dance with the one who brought you" as they say...

Kyle - while we got your ear, care to comment on the widespread banning over there of anyone who says, well, pretty much anything at all that might reveal the truth?
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post #131 of 2629 Old 05-24-2010, 09:29 AM
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wow. i have not been here in a long time, and i had no idea about those new amps V3....sorry they suck as bad as they seem to from what you guys have said.

i am very lucky in that my original 2 mfw15's are still working great with tons of power etc...but i have had several amps blow on the 3rd unit i bought until i sold it...i have never heard of that replacement amp blowing yet...but who knows.

i am giving serious thought to selling my 2 original mfw's just for fear that they might go and i would not be able to get a suitable replacement amp for them. now i'm really thinking.....geeze......

i hope you guy (Crowcain especially) get your problems worked out. i'll be watching
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post #132 of 2629 Old 05-24-2010, 10:08 AM
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Originally Posted by Stereodude View Post

Someone should test both amps with a resistive load (or even better with the driver connected) and see if it really does have more power.

Explain to me how and I'll give it a try.

I contend that for a nation to try to tax itself into prosperity is like a man standing in a bucket and trying to lift himself up by the handle. -- Winston Churchill
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post #133 of 2629 Old 05-24-2010, 10:46 AM
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Originally Posted by volta View Post

Klipsch, you have summed up my feelings very well with your posts. I don't know why we are surprised, we expect changes from AV666 and WKRP (that was hilarious), and we get the same ol same ol. Shame on us for expecting new things from this company

The reality is that they have been promising change going on 4 years. The only difference now is we don't get the biannual first 2 parts of a promised 4 part letter/explanation/apology/throw some friends under the bus type statement from Mark anymore. Those were always fun times trying to figure out when part 3 of the letter would be released right up until part 1 of the new letter came out apologizing for not finishing the last letter. Rinse and repeat.

Edit: And I agree, I love the WKRP line. TADG, lol.
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post #134 of 2629 Old 05-24-2010, 10:59 AM
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Originally Posted by Jed M View Post

The reality is that they have been promising change going on 4 years. The only difference now is we don't get the biannual first 2 parts of a promised 4 part letter/explanation/apology/throw some friends under the bus type statement from Mark anymore. Those were always fun times trying to figure out when part 3 of the letter would be released right up until part 1 of the new letter came out apologizing for not finishing the last letter. Rinse and repeat.

Edit: And I agree, I love the WKRP line. TADG, lol.

I'm going to hook the new amp up via my 2 channel system and remove the AVR completely. Whatever the new amp puts out compared to the old one will show on the meter. I'll try and capture it on video and then post it tomorrow. It will show whatever the old amp can do at a givin setting and then what the new one can do at a givin setting and I'll crank the gain up on the v3 amp and see how it stacks up. I won't need to turn up the gain on the v2 amp because it would blow the driver right out of the box.

I'm going to call Kyle when my day gets less busy. I tried earlier but it was before anybody got there.

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post #135 of 2629 Old 05-24-2010, 11:37 AM
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Kyle may have been at an early meeting of the engineering group, followed by later meetings with the manufacturing group, compliance division, customer service sector, and later inventorying items that have been in deep storage. It's a busy day there!

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post #136 of 2629 Old 05-24-2010, 11:53 AM
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I spoke to Kyle, he tells me people have responded that they like the v3 replacement amps they were sent. I explained that maybe it's possible something is wrong in the preamp board on some causing it do have lower output than designed?

He is going to do some testing at home and I'll talk to him later this week. In the mean time I'm going to do some more testing as well with the amp that I have and take video of it.

Not sure what else there is to do at this point. If anybody has a way for me to test these things with an ohm meter I'd be happy to do so, just let me know how.

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post #137 of 2629 Old 05-24-2010, 12:10 PM
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Originally Posted by KlipschHead281 View Post

I spoke to Kyle, he tells me people have responded that they like the v3 replacement amps they were sent. I explained that maybe it's possible something is wrong in the preamp board on some causing it do have lower output than designed?

He is going to do some testing at home and I'll talk to him later this week. In the mean time I'm going to do some more testing as well with the amp that I have and take video of it.

Not sure what else there is to do at this point. If anybody has a way for me to test these things with an ohm meter I'd be happy to do so, just let me know how.


I think Kyle picked up a lot from TADG over the years. Enough Said !!!
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post #138 of 2629 Old 05-24-2010, 12:12 PM
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I think Kyle picked up a lot from TADG over the years. Enough Said !!!

Well, Kyle has always been fair with me so I'm not going to hang him out to dry. If he asks me for some time to figure this out I'm giving it to him.

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post #139 of 2629 Old 05-24-2010, 01:36 PM
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Originally Posted by cschang View Post

I absolutely agree, but there is no caveat about the sub not being the same as tested, just that the amp has problems. The sub being different than what was tested, and not designed by Mark Seaton is completely different caveat.

The comparison may be done and over, the list/ranking lives on.

Should we hold Craigsub responsible for keeping track of all the changes on all the subs on the list as time goes by?

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post #140 of 2629 Old 05-24-2010, 01:55 PM
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Originally Posted by tesseract67 View Post

Should we hold Craigsub responsible for keeping track of all the changes on all the subs on the list as time goes by?

Of course not. Whatever validity and/or utility the list had, was only for a time that's long since passed. As changes took place, it rendered the list less relevant. There will always be folks who refer to any ranking list as one-stop shopping and be oblivious to changes that a vendor may've made.

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post #141 of 2629 Old 05-24-2010, 02:08 PM
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Originally Posted by tesseract67 View Post

Should we hold Craigsub responsible for keeping track of all the changes on all the subs on the list as time goes by?

Not at all, but he is well aware of this one and hasn't had to track it. As much as the list was created as a service for, as Chu put it, "one stop shopping", it is an easy change.

Also, no other sub on the list has had issues equivalent to that of the MFW-15 that I am aware of.

While the list is less relevant as time goes by, people still use it and are referred to it.

Would listing the caveat be a good service or a bad service to the audio community?

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post #142 of 2629 Old 05-24-2010, 02:25 PM
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Originally Posted by KlipschHead281 View Post

Explain to me how and I'll give it a try.

It's not exactly a trivial measurement to make. It's not hard, but it requires two oscilloscope probes (one voltage and one current) and some time, patience, and dedication where you measure voltage and current and you slow increase the volume and look for clipping. Or a fancy analyzer that you can just hook the output of the amp to and does all the hard work for you.
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post #143 of 2629 Old 05-24-2010, 03:44 PM
 
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Originally Posted by cschang View Post

Not at all, but he is well aware of this one and hasn't had to track it. As much as the list was created as a service for, as Chu put it, "one stop shopping", it is an easy change.

Also, no other sub on the list has had issues equivalent to that of the MFW-15 that I am aware of.

While the list is less relevant as time goes by, people still use it and are referred to it.

Would listing the caveat be a good service or a bad service to the audio community?

A couple items to address. Let's start at the concept suggested by Chu and echoed by Curtis that the list was "created as a service for one stop shopping".

Here was the purpose of the list, from the opening post:

The purpose of this information is to help people to quickly look at a variety of subwoofers and get a pair of scores, some performance numbers, and some listening tests describing the characteristics of each subwoofer. Hopefully, this will provide some assistance when researching for a subwoofer purchase. There will be times that a lower rated sub will work better for someone than a higher rated sub. For example, size, or output, in a lower rated sub may make a difference. Listening preferences may also make a difference. If slam is valued over extension, some subs excel at the 30-60 Hz slam. For others, extension will be the most important issue.

"Some assistance when researching for a subwoofer purchase" is not quite the same as intending for this to be "one stop shopping".

I was first made aware of the situation with the V.3 amp by Klipschhead on Friday, May 21.

On Sunday, May 23rd, after a PM exchange with Klipschhead and subsequent reading about issues others were having with the same V.3 amplifier, and also that the deep bass response seemed anemic in the subwoofers being delivered today, an additional caveat was added to the MFW-15 rating to join the one posted in March, 2009. To put this in more plain terms: The caveat was added yesterday.

It is available for all to see on TCA's forum, and here is the text:

Additional Note - As of May, 2010, The current MFW-15 appears to be a different unit altogether than the pair tested here. This unit has not been tested, and therefore any MFW-15's being manufactured now are no longer considered a part of this list.
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post #144 of 2629 Old 05-24-2010, 04:09 PM
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Originally Posted by Stereodude View Post

It's not exactly a trivial measurement to make. It's not hard, but it requires two oscilloscope probes (one voltage and one current) and some time, patience, and dedication where you measure voltage and current and you slow increase the volume and look for clipping. Or a fancy analyzer that you can just hook the output of the amp to and does all the hard work for you.

Oh, is that all? I do have an oscilloscope but it's been in the basement forever and frankly I've forgotton how to use it.

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post #145 of 2629 Old 05-24-2010, 06:44 PM
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Originally Posted by craigsub View Post

A couple items to address. Let's start at the concept suggested by Chu and echoed by Curtis that the list was "created as a service for one stop shopping".

Here was the purpose of the list, from the opening post:

The purpose of this information is to help people to quickly look at a variety of subwoofers and get a pair of scores, some performance numbers, and some listening tests describing the characteristics of each subwoofer. Hopefully, this will provide some assistance when researching for a subwoofer purchase. There will be times that a lower rated sub will work better for someone than a higher rated sub. For example, size, or output, in a lower rated sub may make a difference. Listening preferences may also make a difference. If slam is valued over extension, some subs excel at the 30-60 Hz slam. For others, extension will be the most important issue.

"Some assistance when researching for a subwoofer purchase" is not quite the same as intending for this to be "one stop shopping".

I was first made aware of the situation with the V.3 amp by Klipschhead on Friday, May 21.

On Sunday, May 23rd, after a PM exchange with Klipschhead and subsequent reading about issues others were having with the same V.3 amplifier, and also that the deep bass response seemed anemic in the subwoofers being delivered today, an additional caveat was added to the MFW-15 rating to join the one posted in March, 2009. To put this in more plain terms: The caveat was added yesterday.

It is available for all to see on TCA's forum, and here is the text:

Additional Note - As of May, 2010, The current MFW-15 appears to be a different unit altogether than the pair tested here. This unit has not been tested, and therefore any MFW-15's being manufactured now are no longer considered a part of this list.

Regardless of what you post, people use the list in various ways. You know that.

Nonetheless, it is great that you posted the note, but I think the changes in the MFW-15 occurred long before May 2010.

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post #146 of 2629 Old 05-24-2010, 06:57 PM
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Originally Posted by cschang View Post

Regardless of what you post, people use the list in various ways. You know that.

Nonetheless, it is great that you posted the note, but I think the changes in the MFW-15 occurred long before May 2010.

The only change that could be proven is the change from v1 to v2. This was noted and has now been changed to note the advent of the infamous v3.

The Craigsub list almost prevented me from buying that sub because of the v1 caveat. MLS talked me into a v2.

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post #147 of 2629 Old 05-24-2010, 09:44 PM
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Originally Posted by tesseract67 View Post

The only change that could be proven is the change from v1 to v2. This was noted and has now been changed to note the advent of the infamous v3.

Craig also "guesses" the driver is different as well. I wonder when that happened? That is why I suggested Craig contact his friend MLS and get some insight.

A lot more can be proven if someone finds the subs Craig tested and takes them apart. For every iteration of the MFW, someone has taken apart and analyzed. Heck, just compare subs from different purchase dates. It would be very interesting. Don't we already know that MFW's have different places where they were assembled?

The point is probably moot, as the MFW will probably EOL'd and replaced with something else.

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post #148 of 2629 Old 05-24-2010, 10:10 PM
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Originally Posted by craigsub View Post

...To put this in more plain terms: The caveat was added yesterday.

It is available for all to see on TCA's forum, and here is the text:

Additional Note - As of May, 2010, The current MFW-15 appears to be a different unit altogether than the pair tested here. This unit has not been tested, and therefore any MFW-15's being manufactured now are no longer considered a part of this list.

Excellent! That update should take care of the confusion... I'm glad you did that and so now I'm thinking everyone can now drop the Craigsub list issue and move on to discussing the merits (or demerits as the case might be) of this new third version amp for the MFW.

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post #149 of 2629 Old 05-25-2010, 04:18 AM
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Well I replaced one of my amps yesterday with a V3 and A/B'd it against one with a V2. First off I am not a professional here, I did perform(in my opinion) a representative test.


Basically I did this:
  1. Level matched with pink noise.
  2. Both subs were side by side in front of listening area
  3. Used test tones from Ethan Winers site(Thanks Ethan!)
  4. Charted the spl outputs nearfield to the port approx 12"
I'll post the plots here when they are done, but I was able to get really close on output with the gain on the sub set 10-11. I'm not sure whats going on with some of the others. Again I was comparing to the V2s "I" have and what is "standard" anymore.

I can say that with these test tones and 10-11 setting on the V3 it hit 88-103db from 10-19Hz(So much for the MFW not doing anything under 30Hz) Both amps peaked somewhere in the 111db range for the volume I set( which was about -30db on the AVR.)

I'll post complete results later.




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post #150 of 2629 Old 05-25-2010, 05:51 AM
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I put something together the data is there for some of you more estute to manipulate.

I DO see the steep roll off after 30Hz, although still >100db well below 20 with the AVR set to -30. Looks like the V3 dips a little in the under 30, and is a little stronger in the 60-80 range. I do want to stress that I was not pushing either amp to their maximum output, but I never do anyways. This is where I would have them integrated for normal theater listening and normally run the AVR at -18 for movies. I backed off the volume since I have fried too many voice coils with test tones and reference output. This set of test tones takes about 15-20 minutes and (in my opinion) thats a lot of demand on any driver.

I did notice while comparing the amplifiers that the capacitors on the V3 are 2200uF and the V2 had 1500, and that the inductor was quite different with the V3 looking nicer and more substantial.

I did not have time to do much demo but I'll do that soon and chime in.

Best Positive- This amp runs COLD even after 20 minutes of test tones it was cold, not cool, or warm, but cold to the touch.

I would recommend anyone replacing their amp to invest in some weather stripping as my new V3 did not have the sealing tape around the amp plate. I also noticed the transformer was a little loose on the bolt, but I left it as it was, I remember reading somewhere you can damage it if you overtighten a toroidal, short out the wires or something.

More to come!

Cheers!

 

V3.doc 263k . file

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