AR's Biggest Little Speaker? AR-18s

[lARrybody]

DavidR Here is a recent reply from Rick to this question.

Hey Larry, part number 610 365 surrounds are the correct for AR 8" woofers.  If you need more, please let me know.

Thx,rc

 

Sent from my Verizon 4G LTE Smartphone

 

------ Original message------

From: Larry Pittman

Date: Wed, Aug 17, 2016 10:58 AM

To: rcobb@tampabay.rr.com;

Subject:AR 25 woofers

 

Hi Rick. I have some 610-365-1 surrounds I got from you. Recently picked up some AR25 speakers which have 8 in woofers. Did not see them listed per say on in your store. Would these be the correct surrounds to use? Thanks

Larry Pittman

I have used these same surrounds on Advent 8 in Heritage and Prodigy speakers. All my 18S's have these. I would be interested to investigate the Boston filled fillet surrounds. I have used this type on 2ax woofers. 

[lARrybody]

Adam  All the cap suggestions JKent recommended are good choices. I like the .33uf Bennic and 4.7 Carli caps wired in parallel idea for the ESR reasons. Here are some of the 5uf Unicon electrolytes I pulled out of mine.  I use the Dayton 5.1uf cap as a replacement.  I also replace the spring loaded clips with binding post.

http://www.parts-express.com/dayton-audio-dmpc-51-51uf-250v-polypropylene-capacitor--027-423

http://www.parts-express.com/parts-express-gold-plated-banana-5-way-speaker-wire-binding-post-terminal--260-302

I also have a set with these installed.

http://www.soniccraft.com/product_info.php/audiocap-theta-5uf-200vdc-p-72

My opinion, save your money, I really can't here the difference.

 

Edited October 10, 2019 by lARrybody
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[JKent]

Good advice from Layybody. I didn't know that speaker used spring clips.

If you get the Carli caps, you could go with terminal cups like this https://www.madisoundspeakerstore.com/terminal-cups/input-cups-d-cup/  You'll need 3" a hole saw to mount them. If you use the binding posts from PE you may as well get the Dayton 5.1 caps. No sense paying shipping charges for 2 small orders from 2 different sellers.

Kent

[DavidR]

Thanks Larrybody. I have eight of them to refoam.

[owlsplace]

5 hours ago, JKent said:

There is some disagreement about whether you should remove the dust caps and install shims. IMHO (and that of many members here) shims are the way to go.

Well, if there is any damage to the voice coil former you will find out quickly by shimming.

RoyC (noticeably absent these days) liked the Carli caps since their esr value was closer to the originals.

Roger

[adam2434]

When soldering in a new cap on the 18S, are folks doing this in-place (through the woofer hole) or removing the board that is stapled into the back of the speaker box?

I'm used to crossovers mounted on terminal cups that have screws, so the 18S is a bit unfriendly to crossover work.

 

[adam2434]

Nevermind, I soldered one in-place.  

One speaker done - ready to test!

Per reco from RoyC, I used these surrounds and caps:

http://www.parts-express.com/parts-express-speaker-surround-re-foam-repair-kit-for-bose-301-jbl-116h--260-914

http://www.parts-express.com/dayton-audio-dmpc-51-51uf-250v-polypropylene-capacitor--027-423

[adam2434]

First refoamed and recapped speaker works!

Bass seems a bit light, which leads to a bit bright overall tonal balance.  It sounds very good, but not much bass.  However, only one speaker is playing in the large, unfinished portion of our basement.  I normally play a pair of NHT SB3 in this area.  I'll report back when the other speaker is done.  I will also test them in a smaller finished space.

Here's a pic of the first speaker.  Serviceable repair, although not the prettiest by pro standards I'm sure.  A bit of glue seeped beyond the edge of the surround when I applied pressure.  Not sure how to avoid this on the next speaker.  I was able to reuse the original dust cap after peeling it away from the black adhesive, starting with an Exacto knife and peeling with tweezers.

 

[adam2434]

The other 18s refoam and recap is done.  Will test tomorrow afternoon after the glue cures around 24 hours.  

For some reason, the second woofer did not go as smoothly - the foam did not want to adhere to the cone and frame, and took constant work and attention to get it to adhere. Hopefully it holds.  I will give them a rigorous test over the next few days.  If the foams do not hold, I will probably just part-out the tweeters.  My intent is to give these speakers to my daughter to use as garage or rec room speakers when she get a place of her own in a couple years.  I showed them to her and she was very appreciative and thought the retro look was cool.

Both woofer frames have some rippling (see pic).  I have never seen this before.  I wonder if this is just an artifact of a crude manufacturing process, or if the ripples are there by design for some reason I don't understand?

I also attached a pic of the Dayton cap, which I soldered in place and hit with a got glue gun to secure to the board.

Based on the appearance of the woofer and some research on earlier models, seems like these drivers date back to the early 70's, although the speakers were made in 82-83. Is this typical for AR?

Here are some learnings and observations from this project, my first refoam:

1) The cone and frame clean-up prep is time-consuming, but straight-forward.

2) I'm glad I decided to shim the voice coil gap.  It added a step, but it was no big deal to remove and reattach the dust cap, and it provided some peace of mind.

3) Centering the surround by eye to the frame does not necessarily center the cone on the surround.  This was apparent when viewing the back side of the cone.  If I decide to refoam again, I will adjust foam placement based on viewing the back side of the cone.  Does this sound right?

Thanks for all of the input.

Adam

 

 

 

 

[JKent]

On 8/30/2016 at 9:08 PM, adam2434 said:

A bit of glue seeped beyond the edge of the surround when I applied pressure.  Not sure how to avoid this on the next speaker.

The PE ad you linked to shows the white glue. If that's what you used, seepage is no problem--you can wipe it with a damp cloth or even your finger. In fact, you can run a bead of white glue around that seam and smooth it with a wet finger to make a tapered transition from the foam to the cone.

One trick with the white glue that may not have been clear in the instructions: It's a bit like contact cement. You coat both surfaces to be joined then let them set up a bit, so the glue changes from white to almost clear. Then carefully put the pieces together. They'll grab right away.

-Kent

[owlsplace]

8 minutes ago, JKent said:

One trick with the white glue that may not have been clear in the instructions: It's a bit like contact cement. You coat both surfaces to be joined then let them set up a bit, so the glue changes from white to almost clear. Then carefully put the pieces together. They'll grab right away.

Normally, I wouldn't do it that way though as I prefer to let the cone self-center while the glue is still fluid and workable.

I think I did around eighteen woofers before I really felt comfortable doing it. I would really be edgy with the fast-set solvent glues used by the big boys although I have used it on two polypro cones I wasn't that happy with the result even though it was fully functional.

Adam, I don't see an issue on these and I think your daughter will be well-pleased when you get them up and running. They look correct for the period -- early 70s would have alnico magnets with yokes.

Roger

 

[JKent]

23 minutes ago, owlsplace said:

Normally, I wouldn't do it that way though as I prefer to let the cone self-center while the glue is still fluid and workable.

I agree and should have given a more complete explanation. Thanks.

You can use the the "contact" method to attach the surround to the cone, then use it wet to self-center as Roger says, to glue the foam to the frame.

-Kent

[adam2434]

The PE instructions did say to apply glue to both surfaces and let the glue cure for 5 minutes before bonding.  I followed those instructions, but bonding was still a challenge in some areas on the cone and frame, especially on the second woofer.  Hopefully it will hold.  I do honestly feel that I put a great deal of time and effort into this, so hopefully the bonds will hold.  If they don't, it was still a good learning experience.

Any thoughts on the other questions above?

[michiganpat]

the issues with the frame of the woofer look like artifacts of the metal stamping process, and this is what AR woofers looked like in the late 70's/early 80's....

[owlsplace]

11 hours ago, adam2434 said:

3) Centering the surround by eye to the frame does not necessarily center the cone on the surround.  This was apparent when viewing the back side of the cone.  If I decide to refoam again, I will adjust foam placement based on viewing the back side of the cone.  Does this sound right?

Yes, correcto mundo ...

[DavidDru]

Give those some playing time before assessing if the woofers are putting out bass.  Took a little time to "break" in mine too if I remember correctly.

[lARrybody]

I have used a small depth scale and little tick marks with a fine point sharpie to center the surround on the cone. Looking at the back side will also tell if it is centered.

Edited October 10, 2019 by lARrybody
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[adam2434]

Mine are not perfectly centered because I looked at the back side after the glue was set-up (a learning moment).  I originally thought that using the surround outer edge to frame outer edge would be a good reference for centering, but learned that this does not result in perfect centering.  

My gut tells me that having the surround off-center a mm or 2 from the cone won't be a problem, as long as there is enough cone to surround bond area everywhere.

 

[adam2434]

Both surrounds are holding fine after several hours of play at fairly loud volume.

I do notice that the second woofer completed seems to have a stiffer suspension when I push on the cone.  Not sure what’s causing that, but I do not hear a difference in the woofers.

Overall, the 18s bass is lighter vs. the NHT SB3 (acoustic suspension bookshelf with 6.5” woofer) that I use in this room (large unfinished portion of basement).  I have them on a shelf about head height when standing, with the back of the speakers around 5” from a sheetrock wall that separates the finished and unfinished parts of the basement.  I think the bass will improve in a smaller room with the speakers near a wall, possibly with the woofers near the ceiling (I’m thinking mounted in the upper corners of a garage or rec room when my daughter has her own house). 

The bass they have is tight and detailed though.  I think they would mate nicely with a musical, sealed sub to fill in the low end.  In general, I am liking the tight bass that the acoustic suspension speakers I own have (18s, NHT SB3, and SB2).  My floorstanders in other rooms are ported (Polk LS90 and Klipsch RF-7II), and I am now interested in trying out some acoustic suspension floorstanders, although options are limited vs. ported.

Back to the 18s, I am pretty impressed with the way these little, entry-level, unassuming speakers sound.  At a glance, they sound better than they should when you compare their dated paper woofer/tweeter and single cap crossover to current models with modern drivers and sophisticated crossovers.  The 18s are an eye-opener for me.  They make me wonder “how much has speaker design/performance really advanced in the last 35 years?”, given that this inexpensive speaker from 35 years ago sounds so good.  I am a bit baffled, but you all are members of a vintage speaker forum, so you must have a reason to like these old speakers.  

I will keep an eye out for more of the model 18 variants.  What are the larger models in this series?  Did they make a larger bookshelf and floorstander in this series?

OK, sorry, enough rambling...

[adam2434]

I found the brochure (on this site) for the AR speakers series that included the 18s (the baby of the series).  Great read - read it twice on business flights this week!  

Reading that brochure gave me the impression that AR speaker design was pretty advanced for that time.

Looking at all the models in that series, it seems like the paper tweeter models might be the lower tier models in that series vs. the dome tweeter models.  Is that correct, and were the dome tweeter models better performers across the series?

[Steve B]

Not sure if this is the correct place to post this as Im new to this. I have a pair or AR18 speakers that I picked up at a market a few years ago. Sound wise Im very happy with them. The woofers are perfect. The bad part is the cases were on their last legs. They had been painted white and were falling apart. I did a down and dirty repair job using wood glue the sort builders use. So I now have good sounding speaks that look awful.

Today I bought a pair of AR16 speakers that have cases that are like new with woofers that are stuffed. I could get them refoamed or rather I'll try it my self. But mty question is can I simply swap the woofers from the AR18 into the AR16 boxes and get speakers that sound as good as the AR18 pair? Any comments appreciated. Regards Steve

[ra.ra]

Hi SteveB, and welcome to the forum. Please try to post a few pics (simple jpg files no larger than 100KB) of both pairs of speakers so that the advice you receive is well-advised and accurate. It is always best to be able to see the specifics of each project, and in this case, there were three versions of AR-18 (18, 18S, and 18B), and the AR-16 model receives very little attention in these pages.

Without yet having seen your speakers, take my comments with a grain of salt, but first, please clarify this phrase: "..woofers that are stuffed." One of the first things to consider with your proposed transplant is that, according to AR literature, the cabinet volumes of these two speakers are very different: 9.77L (0.35 cf) for the AR-18; and 18.0L (0.64 cu ft) for the AR-16. This would tend to suggest that a direct transplant might not be successful. And while all 8-inch AR drivers are physically interchangeable, it appears that the cabinet prep cut-out for the tweeters might be considerably different. 

All versions of the AR-18 are great-sounding little speakers. All versions are also clad in vinyl, and most attempts at painting vinyl are recipes for disaster. I do have one lingering thought about preserving your AR-18's, but I'll withhold that suggestion until seeing the unique condition of your pair.

The AR-16 is somewhat of a rare bird - - I know I've never seen this model - - and not much of a marketing success. Its cabinet dimensions are more closely akin to the popular AR-4x, and while I believe it is probably a very competent small loudspeaker using excellent components, I suspect its failure (in sales) was most likely due to its unique styling that was inconsistent with other AR products from that era. Product literature claims it was available in "simulated walnut wood finish" or "walnut-grained vinyl".    

 

[Steve B]

Ra Ra Thank you for your fast response. I'll add pictures so you can see what i have. FYI both speakers are made in Australia ( I live in Sydney). The AR 18 speakers are in fact 18S speakers painted in Yellow rather than White! I haven't had a good look at the AR 16 speakers but they appear to be wood veneer rather than vinyl. Hope photos help. Regards Steve

[Giorgio AR]

Hi Steve, your AR16s are amazing in the cabinets and grills, the speakers: the woofers just need refoaming and straightening a small fold in a paper cone (not a difficult job), the tweeters are the Peerless KO10DT, among the best players (if functioning just need aesthetic refreshing).
It's worth restoring them to their original components and you'll have a wonderful pair of AR16 mintes!
The AR18s are perfect in the components, the cabinets can be restored and then finished with veneer or painting, depending on your taste!
You'll get more tips on restoring AR18s cabinets from other members ...

Giorgio

[Lomar64]

I had a pair of 18s that I rebuilt using Dayton 5% poly caps and Rick Cobb's filet surrounds. No shimming required when glueing surround to cone by using fast dry adhesive.  Then use standard white glue for frame and move cone as glue becomes tacky.  It will self center, then press surround to basket and let try.  Had no problem selling these on Reverb..see pic.