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That's an amusing story and a great-looking pair of speakers. I like the old Rectilinears, too, but I've never had a pair of the big boys like the III's. That's a lot of screws to remove the baffle board, but pretty easy to get at all the innards once you've done that. I know it's typical for these smaller drivers to be held in place with only silicone adhesive, but are those T-nuts and machine screws used for fastening the woofers? Thanks for posting.

Agreed, the Howard's products can work very well for cabinets that do not require further treatment. And the 1966 dates on yours make perfect sense when compared to the dates and serial numbers noted on my schematic sketch. Thx for the additional tweeter pics, and as suspected, the magnet seems to confirm this hybrid. What you have is indeed the AR-4x tweeter, but with the added metal cage and (partial) fiberglass damping associated with the earlier AR-4 tweeter. Yes, this is associated with the 20uF capacitor, and your wax cap block, like mine, has no identifying labels, which is where RoyC bailed me out. Pic attached shows front and rear of 3.5" AR-4 tweeter on left; and 2.5" AR-4x tweeter on right. Note the difference in magnet diameters.

Sounds like you're well on your way already. Looking forward to future progress reports. Re: grille cloth, it is very typical for the original cloth to have some degree of discoloring, but just one word of caution - - if you have removed it from the grille frame, and then subject it to moisture, subsequent shrinkage is most likely to occur upon drying, which might make it very difficult to re-stretch and staple over the original frame. Other members have various methods for cleaning the linen, but link attached shows my experience: Re: cabinets, great to hear that the veneer is in good condition, and re-finishing of the walnut is fairly forgiving for even the weekend hobbyist. Within limits, the veneer successfully accepts efforts to lighten or darken or modify the coloration. Am still unclear about your "bypass" remarks. Your wiring sketch looks correct, and appears to keep the control in the tweeter circuit as intended. IMO, you want the potentiometer in the circuit for two reasons: [a] it is beneficial to have the variable control for tweeter output to respond to speaker placement and specific room acoustics; and even at full tweeter output, the pot provides a bit of necessary resistance. Great project - - - take your time, document carefully, and report back when you can.

Hi Coleman, RoyC helped me confirm the accuracy of that crossover schematic, and although it's not a bad sketch, it was sort of stupid the way I drew that 24uF cap - - - it looks more complicated than it should. Instead, I should've sketched it so that the 24 cap is simply connected in parallel across the woofer terminals. In fact, I think that is how I built it, with the 24 cap attached to the woofer magnet instead of to the cabinet bottom (back). Either method of installation is fine - - an important thing to note, which both of our sketches show with a dot - - is to ensure the three-point connection where the coil, the 24 cap, and the woofer common wire are joined. Your sketch looks just fine. The only thing I did not understand is the comment "Bypass to 1". Your speakers look great, and this two-capacitor version of the AR-4x (with the AR-4 woofer) is somewhat rare, and they all tend to fall in that ± 28K to 42K range of serial numbers. In fact, yours might be even more peculiar than most because of that tweeter, which looks more like the AR-4 tweet (3.5" cone) than the AR-4x tweeter (2.5" cone). Can you please help confirm more about this tweeter? Could you post a pic of the entire crossover to confirm the tweeter cap value (20uF, I presume?), and also include close-up pics of the tweeter, especially the backside? And measure the diameter of tweeter magnet? Since these speakers tend to suggest the production line transition between the AR-4 and the AR-4x models, I have a suspicion that your tweeters may be the 2.5" tweeter used in the 4x, but with the protective screen and partial fiberglass damping found on the 3.5" tweeter of the AR-4. You have a very interesting pair of speakers. I hope the cabinets and grilles are in good shape as well. I suspect you'll be installing new caps, but you'd be well-advised to also to re-furbish the control pots or replace them (with A-P pots from other AR's or L-pads) and perhaps also apply a light coat of Roy's butyl dope to the woofer surrounds if they feel stiff. Your particular version of 4x shows up very infrequently, and one of the few identifications I've seen of this specimen is from a document sent to me by JKent a few years ago, as shown below.

Fantastic collection, thx for sharing.

One other thing......beware the 1" shaft version will be longer than desired. Shaft length of 3/8" much preferred. Pic attached from RoyC or JKent shows installation. http://www.parts-express.com/speaker-l-pad-attenuator-15w-mono-3-8-shaft-8-ohm--260-248 http://www.parts-express.com/speaker-l-pad-attenuator-15w-mono-1-shaft-8-ohm--260-250

Thx for the additional pics of the mahogany AR-3, Tom. It makes me curious why this gorgeous veneer finish seems relatively rare, given that the mahogany option was between $6 to $10 less in price (per cabinet) compared with the oiled walnut, per the 1971 catalog.

If you read up some more and look at additional images, you'll find a few variations of this speaker model, but there is nothing obvious to suggest that any part of yours are not original.

Yes, your images are viewable, and it appears that all drivers are original. I am no expert on the 10-pi, but according to the various drivers pictured in the AR-3a restoration manual, all of your drivers are from an early version (Mk. I ???): woofer (A.4); midrange (A.13) and tweeter (A.21). I may be mistaken, but I always thought that little (Varec) button was simply a magnet to keep the wooden door closed, and if you view this attached thread, you'll see a pair of 10-pi's with the ID sticker inside the door flap like yours. You've got yourself some very nice speakers there. http://www.classicspeakerpages.net/IP.Board/index.php?/topic/1520-ar10pi-crossover-schematics/

Hey Glenn, those turned out just gorgeous and the new grilles look great. You (and Roy) did spectacular work with that restoration project. Your results look just like this random pic I keep on file. Congrats.

Great job on those speakers, Glenn, and your grilles and frames look terrific. Nice to see the AR-12 (and badge) in a horizontal orientation.

What is the preferred method for trimming the overhang on the veneer patch? Utility knife? Razor sharp chisel? Sanding block? Sledge hammer? And, is that ordinary yellow wood glue used to secure the patch? Thanks.

Hey Glenn, you got another great find there. Gorgeous speakers and great pics. Can I suggest maybe providing some temporary protection on those tweeters while you work on the cabinets? Looking forward to watching your progress. Carry on.

The pair of speaker crossovers shown here (with #5 coils, however) had the same situation regarding mis-matched capacitors, and even though the can-type caps often still measure reasonably well, it is a good idea to replace both 20 uF caps at the same time. You can always parallel multiple smaller caps to achieve this value, or simply replace with a single good quality cap of the same value. And if you want to ensure the best HF performance from the tweeters in your restored speakers, while you are inside, you should also inspect, and then decide whether to clean or replace the pot controls.

I recently re-foamed these same woofers which were Tonegen factory replacements for a pair of AR-7's, and I used the Bose 301 surrounds recommended by Roy C. The Boston foams may be a bit more compliant, but the Bose is a better fit and a very suitable surround. Easy install, but that weird dust cap is a delicate process to re-attach if you use shims. Has anyone else encountered this elastic ring along the inner surround crease? It felt like a thin bead of silicone, and it peeled off with ease. I suspect that its original purpose was to create a profile similar to the Boston filled fillet regarding sound wave diffraction.

Great info from m-pat and RHolt. For those of us who aren't skilled enough to fully understand the mutual inter-workings of driver sensitivities, crossover slopes, and the subsequent effects of caps and coils that go into the design of any speaker model, this is all interesting and helpful information to consider. It makes me want to possibly experiment with adjusting some cap values on some speaker projects where I have transplanted similar, but not entirely original, drivers due to availability.

Sounds very plausible, thanks, mi-pat.

Fantastic collection and great photos - - - the AR-18 (and 18s) does have a fervent following, and I always love to see the enthusiasm for AR's small two-ways. I'm wondering if that small dimensional change accounted for the minor bump in internal volume, and I'm also curious about the change in cap value from 6uF to 5uF. I, too, prefer the aligned drivers in the 18s, but it's too bad they abandoned the two-way tweeter switch from the earlier 18. Thanks for sharing.

Roger, there are more than a few members on this site who know the intricacies of these models better than me (michiganpat, Robert_S, maybe?), but yes, the AR-18, 18s, and 18b all used excellent drivers worth salvaging if all else is beyond repair. Not sure if any of the earliest of the 18's had real wood veneer cabinets, but even the 18 and 18s (see pic) had at least three differences: driver placement, tweeter (both had FF, but different lead-out wires), and woofers. Some '18' models use a 6uF cap; others have a 5uF cap, I think. I have some literature that lists the AR-7 and AR-18 as both having identical cabinet volume (9.77L), whereas it appears the AR-18s is listed as just a tad larger (9.86L). Close enough for government work, and they all have the same x-o frequency (2000 Hz) and use a 5 or 6uF cap, so my guess is that this 18s woofer might serve as a very reasonable substitute for an AR-7 woofer. The 18s woofer should be p/n 200037, same as in this 18b I recently re-foamed. I did not like working with this flimsy, shiny dust cap, but I just slit it, folded it back and shimmed, and delicately glued it back in place. Your question about driver polarity is a good one since the AR-18s has consistent polarity and the AR-7 has drivers reversed. I dunno - - - am still curious about the AR-7 wiring - - - why not try it both ways and report back.

LC simply refers to the two crossover components: inductor (L) and capacitor (C). A bit difficult to follow, but this thread shows a number of these LC devices and mentions the 630 model at several points. http://www.ebay.com/gds/EMI-350-style-combination-speakers-Single-Point-Source-Monitors-/10000000020917667/g.html

Hey Kent, this thread may become of interest to you. http://audiokarma.org/forums/index.php?threads/rare-emi-score.725969/

Yeah, those look really good, Kent, and many of us have encountered those cabinet problems that challenge our woodworking skills. Not long ago, I finished restoring a pair of AR-6's that were really beat up, and I had corner conditions similar to yours that required both gap filler and touch-up markers. I still haven't tried the "tootsie rolls" (Mohawk product?), but I've been having good results using this soft putty-like product - - - it's rather forgiving and the only downside is it dries really fast so you have to work quickly. http://eclecticproducts.com/products/famowood/famowood-original-wood-filler.html This long video shows a boatbuilder using this product, but his excellent tip (with the plastic bag) at the 4:00 minute mark was something I used to extend working time.

I love FM jazz, as well as the Hammond B-3, and the best car my mother ever drove was a lovely silver-blue Olds Cutlass, so I really like the peripheral elements of this story. But really it's the serendipitous synchronicity of pairing these components that is the main course of this meal, and it explains the reason we like to explore, de-construct, and tinker with these dust-collecting items. Really great vintage stuff.

No one wants to end this thread on a sour note. My participation was triggered by some simple discussion about the esoterica of little metal badges, but I will confess that I might tend to get a little overenthusiastic about the more modest offerings from AR's "classic" series - - - i.e., the small 8" two-ways. My previous comments were meant to be yet another cheerleading effort on behalf of the smaller speakers, but I was also challenging the OP's seemingly contradictory statement that he is seeking "something a bit higher up the ....food chain" (which to me often translates to 'larger') while stating the spatial limitations of his living environment. Spensar, stick around, this tent is big enough for a wide variety of tastes, practices, and opinions (you did miss a special bargain, though), but do keep us posted on the eventual acquisition of your 'keepers' once you procure them. And to larrybody, I shook hands with Bobby Kennedy before I ever knew of Acoustic Research and I'm good with that, but there is no snark in this thread - - - all comments have been supportive and cooperative to the OP's questions, and it has been a healthy exchange. You stick around, too - - your posts have been great. But, when the time comes that I feel the need to post a pic of Henry Kloss on my wall, there is no doubt that I will prominently display this visage of HK. Cantankerous genius perhaps? Maybe, but I'm good with that, too.

Thanks, Kent, for clearly stating my exact thought. Am just not clear about how someone who has limited space will be able to accommodate something "higher up the... food chain" (AR-3's?) without spending 20 times as much as this sale required. IMHO, E.F Schumacher said it best when he wrote in 1973, "Small Is Beautiful".