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Kal87bmw

At 9 lower midrange reconed

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My ar9 lower mids and woofers were reconed by previous owner on the mids they used double roll cloth surrounds has anyone had them done like that I keep reading no one offers cloth   Also they have 200044 mids not the 20028s is there any difference  they still sound good 

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2 hours ago, Kal87bmw said:

Also they have 200044 mids not the 20028s is there any difference  they still sound good 

From what I remember the difference is more cosmetic. The 200044 became the AR replacement for the 200028 and 200032.

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13 minutes ago, DavidR said:

From what I remember the difference is more cosmetic. The 200044 became the AR replacement for the 200028 and 200032.

The 20028 mid had more ferrofluild, than the 200044 and 200032.  The 200028 had ferrofluid on both sides of the voice coil, while the 44 and 32 used fluid only on one side.  This slightly altered the resonance frequency, allowing the 44 and 32 to play lower in frequency, than the 28.  That allowed the 200044 and 200032 mids to better blend with the woofers, in a 3-way design.  Being a 4-way, the AR-9 didn't require the 200028 to respond as low, hence the higher resonance, and hopefully, better power handling, with more ferrofluid in the voice coil gap .

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Very good info Stimpy. I remember Carl posting that the 200028 has half the resonance of the 200032. However, IIRC the 200032 and 44 can be used in place of a 200028 but not the other way around.

What I'd like to know is how they are able to keep the ferro-fluid on one side of the vc.

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1 hour ago, DavidR said:

What I'd like to know is how they are able to keep the ferro-fluid on one side of the vc.

I've wondered that very same thing...!

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We were just discussing the 044 driver in another thread by Giorgio, and it is this paper by Tim Holl which explains the ferrofluid issue which differentiates the mid used in the three-way models (032 and 044) from the mid used in the four-way speakers (028). The entire paper by Holl is a good read.

AR-91 and 92 hi and mid - Holl.jpg

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1 hour ago, Kal87bmw said:

Thanks for the help you guys  it’s nice to have this site  not sure how to post pictures but I’ll try

Pictures will help, as I'm a little unclear as to what's been done to the LMR?  Were the 8" woofers really re-coned, or just refoamed, with incorrect surrounds?  And I would think the cloth surrounds should be replaced, as they won't exhibit the correct compliance, of proper foam surrounds.  Incorrect surrounds can easily be removed and replaced with the correct foams. 

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21 hours ago, ra.ra said:

We were just discussing the 044 driver in another thread by Giorgio, and it is this paper by Tim Holl which explains the ferrofluid issue which differentiates the mid used in the three-way models (032 and 044) from the mid used in the four-way speakers (028). The entire paper by Holl is a good read.

AR-91 and 92 hi and mid - Holl.jpg

Another great piece to understand AR mids, this paper explains in a simple way the evolution, the "universality", the versatility and the greatness of this wonderful instrument, and also because, to date, in the form of a replica more or less equal to the original keeps its charm intact.

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They are totally reconed as well as the 12 inwoofers same cone material ribbed paper but they have foam surrounds all magnets appear to be correct 20003 & 200027 I probably got taken but they sound great and I put aside my magnepan 3.6rs  & rel subs

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3 hours ago, Kal87bmw said:

They are totally re-coned as well as the 12 in woofers same cone material ribbed paper but they have foam surrounds all magnets appear to be correct 20003 & 200027 I probably got taken but they sound great and I put aside my magnepan 3.6rs  & rel subs

Wow  I really would like to see what those woofers look like. A lot members here are all in on preserving the originality of these vintage speakers which I agree with, but I also believe that sometimes different modifications can be a good thing. Also some times not so good.  Here are my AR9 lower mids that I refoamed last year with slightly different filled fillet Boston type foams.

EXVudyNl.jpgqtoJAEKl.jpg

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There’s so many different things out there I have the same square magnet same number and mine have 8 holes not 4  tried pics wouldn’t load keeps saying -200 what’s that mean

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13 minutes ago, Kal87bmw said:

There’s so many different things out there I have the same square magnet same number and mine have 8 holes not 4  tried pics wouldn’t load keeps saying -200 what’s that mean

File is too big max size is 199.76. Try resizing to 100k

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The previous owner had all this work done and didn’t have gaskets on the woofers and old gaskets on the rest here’s a picture of the woofers appears to be same cone material

BDE669B0-FC14-4711-90A4-E7287BB82091.jpeg

07066CC6-7854-4914-80A5-24D589A48344.jpeg

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It looks as if the drivers were rebuilt by a decent shop.  Even though they didn't rebuild to stock.  So, if the speakers work, and you like the way they currently sound, I'd leave the speakers as-is.  It would cost close to $600 or more, to source the correct woofers.  So, I'd enjoy them, without any guilt, because you still have a fine set of speakers.

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A while back I ran across some 12 inch woofers in a pair of 9's that were ribbed just like those. I think they were in N.Y. and the guy said they were original cones. I passed.

Interesting surrounds on the LMRs. Are they AR drivers?

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Check the restoration guide, I bet there's nothing like it. I've been staring at AR's fine 12" woofers most of my adult life and have never seen a ribbed one.

Could've been a replacement kit? The VC cap looks over-sized also. I've seen horror stories on the auction where some folks can be handy with a hack-saw and will squeeze some no-name junk in place.

"Kal87bmw" will have to delve into this mystery.

We must consul the AR Gods.

RoyC. where you be?

It's not like years ago when "sound minded" , "johnieo", "SteveF", "PeteB", "DynacoDan", "Minh", and a few others that were knowledgeable for all those years prior.  Now, it's mostly new recruits and learn as you go types. Not that there's anything wrong with that. But, to think my speakers are older than some folks here.

P.S. Correction, I have never seen a ribbed AR 12" newer design woofer in all of my adult life.

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How about the 8 inch LMR? That's also ribbed.

Unless those are the same pair of 9s I saw that makes 2 pair with ribbed cones and I suspect they are not original.

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That 8" seems to have a double roll foam surround also.

On my AR-9's the LMR is not ribbed and, utilizes only 4 screws and not 8 as the one in questions here.

A holiday mystery and the 'OP' is the only one who will be able to sort this out.

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6 hours ago, DavidR said:

A while back I ran across some 12 inch woofers in a pair of 9's that were ribbed just like those. I think they were in N.Y. and the guy said they were original cones. I passed.

Frank and David,

The foam surround/ferrite magnet version of the AR 12  inch woofer in the photo above had a stamped steel basket and a smooth cone (never ribbed). Cone weight and stiffness, spider and surround compliance, and voice coil electrical characteristics are more important concerns than the ribs alone.

The 8 inch drivers do not appear to be AR parts.

Roy

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