Hi, New With New To Me AR-2ax Pair

[sarals]

Well everyone, here they are.  As I said, they were in a BIG box!

The cabinets are decent, but they obviously were used upside down.  The serial numbers are about 3000 apart.  I inspected the drivers in the cabinet from which the seller had removed the grill cloth.  I didn't try to remove the other one.  The drivers look good in the one I could see.  The woofer surround is totally shot, which I knew.  I'm a little concerned that the woofer cone looks like it's sagging towards the mid/tweeter end of the cabinet, ever so slightly.  I pushed on the cone, and it does move freely, but it doesn't take much to produce coil rub.  The three suspension blobs on the tweeter are still pliable.  The midrange, well how can you tell other than try it!  

 

The level controls rotate through their range on both speakers, but who knows what they look like internally.  I hope to get to opening them up Friday or Saturday.  I"m planning on recapping the crossovers, and I'll order the woofer surrounds then.  A 2.7 volt battery test on the tweeters will happen then, too.

 

I do hope the drivers are okay!

[ar_pro]

I see a trip to Home Depot's sandpaper aisle in your future. 

[sarals]

7 minutes ago, ar_pro said:

I see a trip to Home Depot's sandpaper aisle in your future. 

I think so!

[sarals]

I did a quick checkout of each speaker system by connecting them to my HK 630 receiver.  The woofers work in both, the mids and tweeters do not.  That is not definitive, yet.  I'm pretty sure the level controls are a mess, I seriously doubt all four drivers are inop.  Perhaps later today I can devote some time for investigation.  I'll report back!

[sarals]

Are these the appropriate filleted surrounds for my 2ax woofers?  Thanks in advance, folks!

https://www.ebay.com/itm/Acoustic-Research-AR2-AR2a-AR2ax-Foam-Surround-Speaker-Repair-Kit-Best-Filleted/172560432256?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

By the way, I checked the tweeter on one of the speakers with my VOM and a 1.5V battery last night.  6.7 ohms, and it makes noise when the battery is touched to the terminals.  I'm anxious to see how bad things are inside of the cabinets!

~~SS

[JKent]

38 minutes ago, sarals said:

Are these the appropriate filleted surrounds for my 2ax woofers?

I have not purchased from that seller, Rick Cobb aka looneytune 200,1 but he's the guy everyone seems to be recommending these days. The listing indicates this is the FF surround for the 2ax so I'm gonna say "yes." 

I see he includes the white glue, which is MUCH easier to use than the solvent-based glue. My only objection is the inclusion of an "alignment CD" instead of shims and dust cap. Although there are many people who do not use shims I maintain that shims are the only way to do it right.

If I were doing it, I'd get these surrounds plus some dust caps a tad larger than the originals http://www.speakerworks.com/10_Inch_Boston_Speaker_Repair_Kit_p/swkbos10a.htm

Sorry to make things more complicated. You probably can't go wrong with looney tune and the AR woofers are pretty forgiving so far as VC alignment goes, but I aways use shims. Photo below is a 2ax I did about 12 years ago, before we knew about the FF foams. That kit was from M_Sound, no longer in business. btw--Roy tells me the clamps are not necessary.

-Kent

[sarals]

Thanks, Kent!  I assume this is the Allison surround mentioned earlier?

Honestly, I would prefer leaving the dustcap intact.  No question "you can't go wrong" with shims, however.  I'll remove the dead foam and then see how the cones "sit".  They might need shims, they might not.

Thanks again!

[JKent]

8 minutes ago, sarals said:

I assume this is the Allison surround mentioned earlier?

Well, that was Tom who inserted the Allison photo when he quoted me but yes--that's a filleted surround. I used the standard (not "filled fillet") surround 12 years ago. What is recommended now is the "Boston style" filled fillet surround. That's what Rick Cobb sells and is also what I linked to at Speakerworks. 

You obviously know your stuff so you'll decide whether or not to shim but it's quite easy. If you don't like the look of new dustups you can cut around the circumference of the original with an X-Acto knife, leaving a small part attached, then just hinge the cap back while you shim. Be sure to vacuum the VC area before re-gluing the cap then just run a bead of the white glue or Aleene's Tacky glue. I think CSP member ra.ra has posted photos of this method.

-Kent

[sarals]

I know SOME stuff.  I certainly know enough to listen to advice!  I appreciate it, thank you.

[JKent]

2 hours ago, sarals said:

I know SOME stuff

Just heard from Roy, who has done a LOT of re-foams. He writes;

"Using shims allows the adjustment of the cone height and are much more reliable than the test tone.  
Also, It is very easy to slice around the perimeter of the flat 2ax dust cap and flip it back for re-gluing, which is what I do. I would not recommend an over size dust cap in this case."

[sarals]

5 minutes ago, JKent said:

Just heard from Roy, who has done a LOT of re-foams. He writes;

"Using shims allows the adjustment of the cone height and are much more reliable than the test tone.  
Also, It is very easy to slice around the perimeter of the flat 2ax dust cap and flip it back for re-gluing, which is what I do. I would not recommend an over size dust cap in this case."

That makes perfect sense.  I did see a refoaming demo video on "saving" the original dustcap by doing just what Roy said.  It worked very well.  

[lARrybody]

I do it with shims and with the test tone. Once you get the hang of it the test tone works great. I have never had a problem. The surrounds you are pointing to are the ones to use. You don't have to buy the kit, Rick will sell you just the surrounds. rcobb@tampabay.rr.com  The white glue is basically Aleene's tacky Glue and that is what I use. I like the dust caps which are 2 3/4 in and can be found here. You can reuse or make new flat ones which is fine. Shims can be strips of paper or plastic.

https://www.midwestspeakerrepair.com/shop/speaker-repair-kits/felt-dust-caps/

You don't have to use clips, but it is rather colorful.

I make a mixture of distilled water, Aleene's glue and  stamp pad ink to fortify and spruce up the cones. Nowadays I am using grey rit dye instead, just make sure it is thin and mixed well.

 

 

[JKent]

40 minutes ago, larrybody said:

You don't have to use clips, but it is rather colorful.

Couldn't resist 

[sarals]

The second grill is off.  I used the drywall screw method, which worked like a charm.  The drivers look the same as the other speaker, and the woofer foam is just as rotten.  I avoided disappointment there!  I checked the tweeter with my VOM, 6.7 ohms.  I did order Rick Cobb's surround kit, or did I tell you that?  Night shift last night, and I'm a little scattered.

I do like all of the colorful clamps you fellas used when gluing your surrounds!  Very festive!

I was interested to see @larrybody's method of "fortifying" the woofer cone.  I'm wondering if the cone has deteriorated somehow to where it would need that?  They are discolored from age.  I have no way of knowing if they are less stiff than they were when new.

Thank you, all!

[sarals]

I'm back to bore you fellas with some stuff!  :-)  

The surround kit from Rick Cobb arrived today.  I'm sure many of you are familiar with Rick's kits.  I was interested to see that he had a CD enclosed with the kit that contains a 30 Hz test tone to ensure VC alignment.  Because the cones on my woofers sag in one direction, I think I'm going to  make use of that.  I thought I'd use wedges, foam blocks (thank you, jesi!) to level the cones, but I decided I didn't want to cut out the mesh screens over the back of the driver.  The 30Hz should be a great alternative.

I removed the woofer from one of the cabinets this morning.  I'll get to the other one later.  This speaker system showed NO signs of ever having been molested, it appears to be completely original.  I wish I knew it's history!  I thought about reusing the mortite, however, that may not be the best idea.  This cabinet has the cloth cover over the stuffing, which I decided to leave alone for now.  I marked the basket for polarity (red wire), then cut the wires and removed the woofer.  The date stamp on the magnet is January 1971, made when I was a freshman in college!  I certainly knew about Acoustic Research speakers then, and it looks like I've come full circle.  I cleaned the dead foam off of the cone, it just pealed off ever so nicely.  The basket required a #11 Xacto blade, but it also came away clean.  I cleaned up the basket and the edge of the cone with isopropal alcohol, and then test fit the surround.

And that's as far as I've gotten for now.  I'm going to remove the woofer from the other cabinet and get it prepped for the surround replacement.  I have a recording gig tonight, and I don't want to get ahead of myself.

I'll report back!

 

[bfastr]

That is fantastic news!   The stuffing looks like its never been disturbed. That is promising. I would rather have things original and worn out than "fixed" by someone else.

 

[frankmarsi]

Listen here you two new crazy kids on the block, bfastr and sarals.

Please indicate how the re-foaming job is coming along. It appears as if you both will be using the 'filleted' surrounds.

You may recall I wasn't familiar with these and when I asked I was given the run around with no clear answer. Who cares they appear just like I thought they'd look like after I did a search to be sure.

I'm curious if they have additional weight and if their shaping proves a bit difficult in glueing the inner edge to the cone itself.

FM

[bfastr]

LOL !!

 

Frank,   You will have to wait for Sarals to install them. My Speakers are the earlier version with the cloth surrounds,  so I have a different set of challenges. Most of my work will be on the crossovers and inside. 

Bob F

[bfastr]

I have a question for the experts. Which grill badges should my 1968 2ax models have?  they are the cloth surround vintage and Alnico woofers. I see what looks like early 2ax's with a large "ARinc" in one corner and a script "a" in another, and then I see 2ax's with the AR-2ax badge.  Personally I like the simplicity of the big ARinc badge. But, I am also a stickler for having them the way they came from the factory. Maybe the big ARinc are on 2a's ? 

 

Bob F

[lARrybody]

Both my early 2ax's came with the square ARinc. badges. They were missing the "a" badges.The rectangular 2ax badges did not appear till some time in 1970 when the foam surround woofers appeared. My 2a's had the "a" stick pin badges, but I have seen 2ax's with and without them.

The two badges on the left are reproductions along with the "a" stickpin badges. The two on the right are original.

 

[bfastr]

Thanks!  Simple it is.  They will match my AR-4's too.  I can live without the stick pin "a".  

[JKent]

3 hours ago, sarals said:

I thought I'd use wedges, foam blocks (thank you, jesi!) to level the cones, but I decided I didn't want to cut out the mesh screens over the back of the driver

That's why we use shims.

 

3 hours ago, sarals said:

I thought about reusing the mortite, however, that may not be the best idea. 

you can get "duct seal" at Home Despot or other store in the electric supply dept. A brick of way more than you will ever need is about 3 bucks.

3 hours ago, sarals said:

This cabinet has the cloth cover over the stuffing, which I decided to leave alone for now.

That's Kimpac, a paper product meant to keep fiberglass dust out of the woofer. It's pretty fragile so just figure on replacing it with a piece of crinoline or similar cloth.

Lookin' good so far!

Kent

[sarals]

Thanks, guys!

@frankmarsi, the filleted surround kit came from Rick Cobb.  I got mine on eBay.

https://www.ebay.com/itm/Acoustic-Research-AR2-AR2a-AR2ax-Foam-Surround-Speaker-Repair-Kit-Best-Filleted/172560432256?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

He got them too me in two days.  The surrounds fit this particular woofer perfectly.  There is still a small glue bead on the cone, about 3/16 of an inch from the edge, and the surround sits on it.  I'm not sure, but I think that's okay if the new surround is glued properly.  The cone is just too delicate to risk scraping it off, and soaking it with alcohol, altho cutoough it gets the foam bits, doesn't touch the glue.

@bfastr, yes, I SO pleased to see that these speakers are totally original!  Like I said, I wish I knew their history.

@JKent, I think I can save the Kimpac.  At least, I'd like to try.  Thanks for the tip on the duct seal!  I will get a blob of it!  I am very, VERY reluctant to cut the dustcaps.  I know it can be cut most way around and then folded back, out of the way, but I really don't want to do that.  If I really have, that's another thing.  I know the shims are foolproof.  I don't see why the 30 Hz tone method wouldn't work well, either.  I'm open to suggestion, chewing out, whatever!  :-)

[RoyC]

3 hours ago, sarals said:

I know it can be cut most way around and then folded back, out of the way, but I really don't want to do that.  If I really have, that's another thing.  I know the shims are foolproof.  I don't see why the 30 Hz tone method wouldn't work well, either.  I'm open to suggestion, chewing out, whatever!  :-)

I've been re-foaming drivers for a very long time, and presently do much of the re-foam work for "Vintage AR", and all of it for a local repair shop. Inexperienced re-foamers using test tones, batteries, and eyeballs to center old woofer cones have been good for business. There are some woofers (not AR) that have plugs under, or in lieu of dust caps. These are the only type for which I don't use shims.

The shims are much better at compensating for a less than perfectly aligned, or worn suspension, and allow the height of the cone to be precisely manipulated during the gluing process.

Of all the old woofers, the flat dust cap of the 2ax woofer is the easiest of all to retain. If you don't have one, acquire an exacto knife (and some .007 inch shims).

Roy

[Aadams]

4 hours ago, sarals said:

I'm open to suggestion, chewing out, whatever!  :-)

 

1 hour ago, RoyC said:

I've been re-foaming drivers for a very long time,

Sarals,

OZ has spoken,  you are now in "we tried to tell you" mode.  

Adams