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Hmmm, perhaps "incised" was a poor choice of word - - the recessed depth of the letter forms is probably created by an acid etching process or something similar. In any case, I just recently discovered what I think is the most effective and easiest means of cleaning up these badges, as shown on these AR-7's from two weeks ago. Using a metal polish and a piece of scrap cotton flannel, it's just a little squirt and a rub-a-dub-dub, rinse, and Voila! No other abrasives required. These badges were not heavily tarnished yet look at the verdi-gris left behind on the fabric swatch. Using this method, I'll probably re-do other "etched" badges, and then inhibit further tarnish with a light spritz of clear lacquer. Have not yet tried this with the black variety, nor have I found another suitable method for cleaning these.

Kent, you are correct about the TT badge, shown here in upper right of first pic still attached to wood plinth - - - it is same size and similar appearance to black 4x badge but with incised lettering - - a nice little detail. Also interesting to note that some badges are attached to steel backer plate/screw, and others are simply all brass.

Yes, welcome to the CSP forum, Spensar. I hope you come home with that quartet of 4x's tomorrow (or could they be 4's?). The AR-4 has a small square badge (15/16") with black "AR Inc." screen printing. This same badge was used on the early 4x's, but was later replaced with a small square badge (7/8") with an incised "AR" in red-brown lettering. This later incised style was subsequently used in the following models (and maybe others?) in various rectangular formats: 2x, 2ax, 2xa, 3a, 3a Improved, 4xa, 5, 6, 7, MST, LST and LST-2. I believe the much-maligned AR-8 never earned the incised badge, and I am not sure if this version ever showed up on any AR turntables. See below for two versions of small square badge.

I would be inclined to agree with Kent that both drivers are probably intended to deliver similar frequencies, but then again, it's a bit unclear what all is going on with that crossover board - - there are two resistors and one cap, and is that a coil, too? What this idea has brought to mind is a speaker model from several years later - - AR's MST-1 (3-tweeters, all identical) - - where the side mounted tweeter has a small additional cap in order to perform differently from the front-facing tweeters. The MST, of course, is a rather unique design regarding dispersion and an entirely different speaker, but is it possible that the 1uF cap in this KLH is associated with only one of the two small identical drivers? And here's a nice little ad from 1964 for the KLH Fourteen in both styles (S-slimline and B-bookshelf), including some high praise from Julian Hirsch.

Your work looks very neat and precise, so I do hope they play well.

Re: "thick", I suspected so, but just was not sure. On the cones, I'm only trying to offer a word of caution since I know how tenaciously some substances adhere to those heavily textured paper cones. It appears you may already have an excellent surface to attach the inner foam, so I would hate to see you make it worse.

That black ring on the cone perimeter looks so smooth (except for that one location) that I'd be tempted to attach the new surround directly to that existing rim. With regards to trying to remove that ring, my concern would be the possibility of doing more damage to the cone than making any improvement. Why remove it - - are you concerned about added cone weight? My thought would be to leave cone as-is and simply clean up the metal basket frame to ensure a neat glue joint. In your first post, you mentioned that the rubber surrounds were "very think", and it is unclear if you meant "thin" or "thick".

One additional thought to consider. Unlike the AR-3, which was still considered a bookshelf speaker (albeit a large one), both the High and Low versions of the Rectilinear III were intended to be floor speakers, as suggested by their integral wood bases. Compared to the AR-3 which offers a vertical or horizontal placement orientation, the Lowboy, with the wide and squarish proportions, has a very different presence as a piece of 'furniture' in a room. I have seen pics of the Lowboys raised up on additional stands to elevate the drivers, but the speakers look sort of ridiculous when lifted this way. For interest, a pic of two versions of Rect III "Highboys" is attached.

You cannot only compare the cabinet depth - - - all three dimensions that make up internal cabinet volume need to be considered. For example, the AR-17 and AR-18 are nearly identical speaker models - - same drivers, same HF control, same x-o - - but the AR-17 has a slightly larger cabinet volume and subsequently deeper LF bottom end (43Hz) than the AR-18 (48 Hz). Why AR felt the need to manufacture the AR-17 is beyond me, but how else can this slight LF performance boost be explained?

Have never done a side-by-side of these two models, but I am a big fan of early Rectilinear models. I'm sure you already know that the Lowboy was a re-packaged (different cabinet proportions, fretwork grille) version of the highly regarded Rectilinear III, which subsequently came to be known as the "Highboy". These models were probably targeted toward some of the market share that was dominated by the AR-3a, but they are distinctly different speakers. They have six drivers (12" woof, 5" whizzer mid, plus two small tweets and super-tweets), are ported (bass reflex), and have nominal rated impedance of 8 ohms. I'd suggest you go and give them a good listen, then decide. Julian Hirsch gave them a big thumbs-up in this 1972 review. http://sportsbil.com/stereo/rectilinear-db/lowboy-review-hirsch-2-1972.pdf

lakecat's comment about the bass response from the AR-12 made me curious, and I was surprised to learn that, unlike the earlier "Classic" series where the 10" AR-2ax and AR-5 had less cabinet volume than the 12" AR-3a....... in the ADD series, the 10" AR-12 (and AR-14) has the same cabinet volume as the 12" AR-11 and AR 10pi models. Two possible benefits? Maximize manufacturing cost economies of scale, and get an extended LF bump for the 10" woofer.

Hey Glenn, as with all of your salvage-restorations, those AR-12's look terrific, and I did follow your progress over on AK. This speaker just does not show up all that often, so I am pleased to see a pair so carefully restored, and I am sure they sound great. What makes this model unique is that odd mid-range driver, which I believe may not have found its way into other AR models. Great work, thx for the post.

Thanks, Tom, for distributing the sad news and providing the photo. This attached pic from 2014, cribbed from another website, has always delighted me. This woman had just purchased a pair of speakers directly from Roy in NH, and their mutual joy with this particular transaction appears evident.

Great pics and nice work with the new T-nuts, and yep, 30-degree rotation sounds right to me. While it's nice to bite into fresh "wood", am just wondering if maybe you could have simply enlarged the original screw holes (for the new nuts) and avoided the dimensional clash with that mid box.

Re: woofer attachement, it'll be hard to improve on one of the very best details found in vintage AR cabinets - - - T-nuts. This pic is from that excellent AK thread on the restoration of rare KLH-28's.

Hi Geoff, Looks like you have a great pair of speakers and a very nice project here. Your documentation is excellent and enjoyable to follow. I am no expert on KLH or AR speakers, but with regards to your dates, I have had a similar observation with a pair of early AR-6's. The AR-6 is purported to have been debuted in '72 or maybe late '71, but I have a pair (serial numbers close to 04000) which have driver date stamps from Jan 1971. So, give or take a calendar year, it makes little difference. It seems you have obtained a very fine set of speakers. Totally agree with you about the wood screws - - - that type of particleboard is particularly crumbly and certainly would be improved with a better machine screw attachment. Keep up the good work and great posts.

Hi David. I suspect you've already seen this, but just in case you have not, this (long and) excellent restoration thread provides great detail on that rare KLH Twenty-Eight model. They certainly are unique loudspeakers, and like yourself, I've also become very curious about them. http://audiokarma.org/forums/index.php?threads/klh-model-28-rare-find-restoration.577202/

Yes, that chart seems to be one year late on those several models, and I would also add the AR-4, since I have a pair with cabinets and wax capacitors with a June 1964 date.

I came across this simple little graphic that pretty much corresponds with Tom's early timeline from post #15. Despite the lack of specific mention of calendar years 1959 (AR-3 and 2a) and 1964 (AR-4), it seems to serve as a fairly accurate thumbnail reference for the bookshelf "Classic" models.

Jeff, I love that high-tech approach to customizing the label for the AR-1w. Tom, thanks for the corrections on the speaker dating - - it certainly makes sense to have them produced with sequential model numbers as you have pointed out. Occasionally, I refer to the attached chart for a quick look-see at the general product line, and clearly this list must have several factual errors. Not only with dates, but some lesser models (i.e. AR-1x, AR-MST) are not even mentioned.

Tom, that's a great explanation and a terrific pic, thank you. That impedance change to 8-ohms is a bit of a head-scratcher, and it's difficult to imagine what the implications of this change actually sound like. It's good that you mentioned that implementing this mode does not correspond with the use of 8-ohm amplifier taps. Is that crossover also using woven fabric-wrapped hook-up wire? The crossover is interesting for the reasons you mentioned, but it occurs to me that this set-up is simply an early version of a three-way switch, not dissimilar to what showed up in AR speakers 15 to 20 years later after the A-P pot controls were abandoned. Speaking of those pots, did they first show up in the AR-3, or were they used in later versions of the AR-1? And, it's probably been explained on these pages ad nauseam, but why did the AR-3 precede the AR-2 when these early speakers were typically released sequentially? BTW, it looks like the OP's speaker might be mahogany?

Great stories from Jeff, Tom and tekno - - - thanks, all. You know you have an early AR when you see the 25 Thorndike address on the label. About that label, since it contains a whole section of irrelevant notes on High Frequency Adjustment, this is obviously a one-size-fits-all label shared with the AR-1. But still I have a question about the notes under the Amplifier Connection section and the three rear terminals. Can someone please explain the 4-ohm and 8-ohm connection notes that seem to be dependent upon the speaker placement within the room?

Regarding AR's 10" two-ways, let's not forget that the 2x had two versions (each with distinct woofer and tweeter), and both of these were preceded by the original AR-2 with its dual tweeters (at right in first pic attached). I think Tom's comment about the silicone in the AR-8 tweeter referred to grease (precursor to ferro fluid) used in the VC gap, and not a "dope" application, which I tend to think of as a topical coating for cones, dust caps or surrounds. It is quite possible that the AR-8 tweeter was unique in this way, but I have always thought of it as being the same part number that was concurrently used in the AR-4xa, AR-6 and AR-7 from the same period (second pic). Also interesting is Tom's remark that the earliest AR-8 woofer was unique regarding its greater sensitivity, which seems to be confirmed by the catalog page in post 2 which suggests a minimum power requirement of only 15 watts for the AR-8, as opposed to 20 watts for the smaller AR-6.

More info on the simple crossover. http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=6921 Oops, apparently some AR-8's did have real wood veneer cabinets. Based on comments herein, I'd guess very early American AR-8's did have real veneer and even the pot control for the tweeter. http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=8033 And, I assume you're asking about the larger USA AR-8 and not this cute little Euro AR-8s.

Here is one crossover pic, which suggests the woofer running full range, the single 10uF (or paralleled 5uF) caps for the tweeter, and the two 3 ohm resistors on the 3-position switch. Below is the thread where our man Roy has confirmed this. Also, the square badge is original (but with light grille cloth) and the AR-8 came in vinyl cabinet only. I have one parts list from 1975 which shows the AR-8 woofer listed separately from the AR-2ax (late), AR-5, and AR-LST-2 10" woofers, so perhaps it was tweaked a bit to accommodate the anticipated high volume levels of rock music enthusiasts, to which this speaker model was marketed. http://www.audiokarma.org/forums/showthread.php?t=490038