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Acoustic Research AR5 tweeters shot

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I'm sure Chris sealed the tweeters properly.

The "woofer test" is simple: Put 3 fingers on the cone, like a tripod, around the perimeter of the dust cap. Push in. The woofer should return slowly. If it springs back immediately there's an air leak.

If you have not resealed around the woofers they'll fail the push test. An acoustic suspension speaker depends upon a sealed box to get the best bass extension so yes--resealing (I assume you mean gaskets or duct seal) where the woofers meet the cabinets should make a significant improvement.

Regarding the corner; if it's just cosmetic and it's in a place where you can't see it easily you're ok leaving it. OTOH, if it goes all the way through (unlikely) the cabinet will leak air. When/if you decide to do the repair post some close-ups. Glenn is the expert at this but the basic procedure (I may be repeating myself--have not re-read the entire thread) is to dig out as much of the crumbly swollen wood particles as you can, then see if you can draw the corner together with long bar clamps. If not, dig out some more. When the fit is good put some epoxy or epoxy mixed with wood powder (from a sander dust catcher) in the void and re-clamp. Wipe off any that oozes out with solvent and put some way paper under the clam's jaws so you don't epoxy the clamp to the cabinet.

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Your Euro AR5's are looking good. I have two sets of these. My first set came to me fully restored. They have the early woofers. The resisters were to tone down an L-pad and  have subsequently been removed when 15 ohm 25 watt rheostats were installed.

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The second set were a different story. They came with the wrong HiVi tweeters and backwired AR 3a midrenges. They have been converted back to front wired original drivers.

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The tweeters measured 6.6 ohms and 6.8 ohms respectively. The midranges both were 5.9 ohms. The reason I mention this is have you measured your Midranges?  Get the gaskets sealed on those drivers and enjoy these excellent speakers.

 

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On 8/26/2019 at 10:59 AM, JKent said:

I'm sure Chris sealed the tweeters properly.

The "woofer test" is simple: Put 3 fingers on the cone, like a tripod, around the perimeter of the dust cap. Push in. The woofer should return slowly. If it springs back immediately there's an air leak.

If you have not resealed around the woofers they'll fail the push test. An acoustic suspension speaker depends upon a sealed box to get the best bass extension so yes--resealing (I assume you mean gaskets or duct seal) where the woofers meet the cabinets should make a significant improvement.

When doing the push test, after you push in, hold that position for at least 10 seconds so that the air pressure stabilizes. Then quickly release the cone to see how long it takes to return to resting position. One second or longer to return is good. Less than 1/2 second indicates air leakage, either through the surround or elsewhere.

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On 8/26/2019 at 9:59 AM, JKent said:

I'm sure Chris sealed the tweeters properly.

I asked the question anyway... and YES, he did seal the tweeters properly. the rest of the cabinets leak. NO delay when doing the woofer test. but the woofers are NOT sealed yet. I didn't expect them to pass. but I wanted to see how bad they are.

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On 8/26/2019 at 2:17 PM, lARrybody said:

The reason I mention this is have you measured your Midranges?

hey IARrybody - nice! there's another set listed for sale about 3 hours from me. I've been trying to get a reply from the seller for about a month. to no avail. I can only assume he doesn't really have them.

regarding my mids - no, I have not tested them with my meter. they seemed to be performing fine, they sound great. and with having to de-solder them from the front mounts in order to test, it didn't seem worth the trouble. I was also told by the guy that rebuilt my tweeters that these mids are very hearty and he doesn't see many that need servicing.

noteworthy on these Euro AR5's... the cabinet dimensions aren't the same as standard AR5's. I got a set of replacement grille boards from vintage ar on ebay... they're too small. Larry with vintage ar is working with me to get grille boards that work. I'm shipping him my single bad one... it's in pieces but all pieces are intact. and his carpenter is going to make a set from my wrecked one. luckily, Larry's cool. I've been sitting on these since April and he's still taking them back and working with me on a suitable replacement. I highly recommend vintage ar if you need parts.

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On 7/11/2019 at 11:08 AM, JKent said:

Welcome to CSP

Yes--those are the ones, but let's slow down a bit. Here are some thoughts:

  1. Vintage AR is a reputable ebay seller. I purchased some things from him when I was getting started with this hobby. But bear in mind, it's a business and he needs to make a profit. The tweeter he sells for $69 can be easily put together or about $20 or so each. RickB sent a link to the tweeters, the coils are here: https://www.parts-express.com/dayton-audio-005mh-18-awg-perfect-layer-inductor-crossover-coil--257-798
  2. You can find lots of info about the HiVi mod by googling hivi tweeter inductor site: classicspeakerpages.net
  3. I'm not 100% sure the HiVi mod will work as well in the AR-5 as it does in the AR-3a. The 5 is 8 Ohms, the 3a is 4 Ohms. You may have to use a different inductor. Member RoyC is really the expert on this so maybe ask him.
  4. Why would you go through the work and expense to install the HiVis as a temporary fix while waiting for Chris to rebuild the originals? Delayed gratification is a virtue ?
  5. And speaking of RoyC, he's the "inventor" of the HiVi mod and has researched this extensively. But he also rebuilds tweeters. A lot of the stuff sold by Vintage AR is Roy's work. Why not PM him and ask if he would rebuild your originals? He recently rebuilt some AR-3a tweeters for me and they are excellent. They're shown in this write-up: http://www.classicspeakerpages.net/IP.Board/index.php?/topic/10638-another-ar-3a-restoration/

Let us know how you make out, and please post some pictures (resize to about 100Kb or so).

-Kent

So, reviving this post a bit (apologies) but I dont think the question of the HiVi modification working for the AR5 tweeter has been answered. I'm understanding that the AR5 tweeter is an 8 ohm verses a 4 ohm for AR3. 

I too am restoring a set of AR5's where one tweeter is officially toast. I'm not against replacing both with the mod but I still dont know if using the standard mod that everyone discusses will work.

If the tweeter replacement is a 6 ohm, does there need to be a different inductor and if so what would be the correct way to do this.

Appreciate in advance any and all responses.

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The HIvi mod is is pretty well settled, having changed only slightly from the original advice in the Restoration Document.  Everything you need is in this thread

If you are in the US you might want to consider having your tweeters rebuilt rather than Hivi mod.

Adams

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Welcome Micer!

Adams gives you a good lead but being new to this forum you may be a bit overwhelmed.

So, yes, you can use the HiVi tweeters. This is cheap and effective. btw, I just went back and edited the post you quoted to include the info Adams has pointed us to. Thanks, Adams.

Or, as Adams wrote, have the originals rebuilt. CSP members RoyC and Chris1this1 both do rebuilding, although their methods differ.  This will be more authentic (in appearance at least) but more expensive.

Here's Chris's ad: http://www.classicspeakerpages.net/IP.Board/index.php?/topic/10049-ar3a-and-ar2ax-tweeter-rebuilds/&tab=comments#comment-119884

And here's a thread on an AR-3a restoration I did using Roy's tweeter rebuilds: http://www.classicspeakerpages.net/IP.Board/index.php?/topic/10638-another-ar-3a-restoration/

 

 

-Kent

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I've reached out to Chris but havent heard back yet. I'll likely go with the mod for now and after the holidays have the originals rebuilt. Still waiting on my 74 uf caps to show up (backordered)

Thanks for the quick responses. You are correct about all the info being overwhelming but I'm glad it's all HERE!

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The originals will be arriving at Chris's place very soon. After corresponding with Chris, he said the originals are good candidates for a rebuild. Feel much better about this route verses the HiVi just to keep some of the originality. Attached photo of how they looked as I sent them out. Just for the record, these are marked as Sept 1971.

 

 

20191203_202235.jpg

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10 hours ago, Micer said:

The originals will be arriving at Chris's place very soon.

you're in good hands. Chris rebuilt my AR5 tweeters a few months back. they sound incredible and the turnaround was very impressive. I've got a few more pieces I'm sending his way as soon as funds allow (after Christmas). AR3a woofers... and probably the tweeters too.

good luck. and enjoy!!

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