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Like Jeff has already said, that really is a great story. Speaker appears to be in fine condition, too. While it certainly wouldn't hurt to list it for sale here, I suspect you'll find fatter wallets on other online venues. A good listing would include clear pics of all six faces of the cabinet, and sufficient info to be able to discern which type of rear terminals this has, as well as serial number and AR facility address (Mt. Auburn St. or one of the Thorndike St. addresses). Looks like you might have lacquered mahogany cabinet (?), so you might want to confirm that as well. Thx for sharing, best of luck with the sale.

Welcome to the forum, Giovanni. The AR-6 is a terrific small bookshelf speaker, so hopefully there might be something here which is useful to you. And thanks, David, for the translation. The original post info is much better now, but still a bit difficult without any photos. Schematics for AR-6 versions A and B are attached. This is purely speculation, but from your description, my guess is that you have a woofer circuit from version A and a tweeter circuit from version B. The added components (10-ohm R and 24uF cap) on the woofer B are found only with that unique woofer, so I suspect you basically have version B speakers that probably use the more common 001 "universal" 8-inch woofer, which does not require the added resistor and cap. I would think the performance of your speakers should be comparable to the other versions - - is there a particular problem you are concerned with? Perhaps posting some pics would be useful to describe your situation.

This comment is from a 2014 thread about AR speakers, but it basically applies here as well. As for color, the original cloth surrounds were made from an orange-tinted cloth material, and with the butyl-latex (originals were not water-based) clear material applied, the surround looks orange or yellowish orange in appearance, which is 100% normal. Later, AR (and others) added lamp-black dye to the material to make the surrounds black and thus not be noticeable through the grill cloth. No real difference in performance, except that the early orange-colored surrounds seem to remain somewhat better sealed over time. Perhaps the lamp black causes the material to harden sooner. —Tom Tyson

I suspected that probably your comment was mostly about size, and IMO, your observations are correct about what most people find suitable in today's balance of home accessories vs. interior decor. (Alexa, anyone?) KLH Twelves are indeed large loudspeakers and therefore have a limit to their appeal or usefulness. The inclusion of the brochure pic above with the sculpture on top and the low cabinet profile is meant to suggest how this speaker can begin to calmly integrate with a certain sophisticated interior aesthetic. Compared to say, an AR-9 - - which, to me, has very serious WAF issues - - and the KLH Twelve almost seems like a cuddly favorite house pet. OK, a St. Bernard perhaps, but......... Several years ago I stashed away that pic of your Twelves, and with the new grille cloth, oiled wood, and fresh badge, your restoration really does show off the beauty of this model. Typical fine work from you, and as you've stated, a truly great speaker. See the KLH blurb attached - - I always enjoy some of the informal language that KLH used in their literature. The Twelves are definitely worth taking a close look at - - - they are a rather unique speaker model. Price will be, of course, a primary factor, especially with speakers that have already had significant "work" done on them. And then there's the issue of practicality - - - you already have a very fine collection of excellent classic loudspeakers, and the Twelves do require a bit of dedicated real estate. But if you do have the necessary space, budget, and level of curiosity, most likely you will find these a very enjoyable addition to your collection.

Pic of KLH Twelve woofer attached - - - most notable by double deep magnet - - I think otherwise identical to woofer used in the Five. Kent, I have heard you express this before, but I don't understand where this sentiment comes from - - - please explain. The materials and finish on a set of Twelve cabinets is about as close as you can get for contemporary period "furniture", and the box proportions are wonderful. Even the crossover control boxes have very nice wood veneer. With the "mid-century modern" aesthetic being the latest craze of the urban hipsters, I'd think these would be highly sought after. Pic of your elegant pair attached.

Sometimes the butyl sealer used for the surrounds (and dust caps) contained lampblack, which results in the appearance you are asking about - - same was used on this pair of woofers in KLH Thirty-Two's.

I think this woofer still retained the 003 part number.

Hey, gonzo - - - yep, that's the exact same component that I spotted last year. Am still a little curious about this ESW, but the follow-up chatter in that previous thread did not suggest it was a particularly suitable device for use with my stable of older, small speakers. That asking price is nowhere near where it was when it was offered to me, so clearly this is a situation where a 'bargain' local purchase is being peddled to a much larger shopping audience at an inflated price. In other words: ebay in a nutshell, or mercantilism in action. Not complainin'.... just sayin'.

Hi Giorgio, that is a very nice-looking pair of 4x's and you're right, the 8-inch woofers with that damping ring are not very common. By all appearances, those are a fully matching pair - - - both woofers with ring and only four screw holes in basket; red plastic control dials on potentiometer; and identical panel materials for cabinet construction. Grilles, badges, veneer and labels all look virtually identical as well. There may be no obvious explanation for the jump in serial numbers from ±6000 to ±7000, but perhaps some of these thoughts might offer some context. What you interpret as "fa" is actually a sloppy handwritten version of "FX". AR-4 speaker label serial numbers began with a designation "F", and once the model 4x was introduced this became "FX". Since you are in Europe, and these speakers date from 1969, I am going to suggest that the "H" notation designates the AR facility in Holland, which I believe opened in Amersfoort in 1969...... and it seems comprehensible that the AR printed labels did not yet reflect this Holland address below the usual Cambridge address. It is also understandable that you would think these s/n's should be much higher by 1969, but it is clear that the Euro numbering did not fit sequentially with USA production units. Just for example, I have several pairs of USA AR-4x's nearby, and their numbers and dates are as follows: ±38000 (1966); ±159000 (1968); ±318000 (1970); and ±383000 (1971). I hope maybe some comments here might be helpful to you.

Hi Scoup. I have only recently become familiar with DA speakers, too - - in fact, I began a thread here a few months ago about some model D-4 speakers that came my way. With the exception of that dome tweeter, your front drivers (all Peerless?) look similar to what's in the D-4, but I'd love to see pics of your woofers, if possible. Also, am curious about the crossover cap value for that 5" midrange driver. Your story about the performance evaluation is pretty strange, but at least they are now providing some very satisfying results. DA speakers are not all that common, but the model D-8 seems to be an especially rare bird. This may not read all that well, but here is a 1973 article by designer George Sioles on omnidirection. Also, a brief listing of DA models from a 1977 buyer's guide.

Hey Pete, Very nice restoration-mod project with the addition of the L-pad and robust wire terminals. These are a great speaker model and yours appear to be in very fine condition. According to info from Human Speakers, your black plastic tweeters with phenolic dome incorporated ferrofluid; whereas the earlier paper dome masonite tweeter employed a foam and silicone suspension/cooling. I have an early pair of 100's that are placed about 7 feet high atop shelves full of folded clothing and connected to a modest NAD receiver that nicely fits the shelf depth. My speakers have rubber surrounds, masonite tweeter, and the original pot control - - very nice veneer, too. It makes a great little bedroom rig - - these speakers are classics.

Hi Swilli, it is still a little unclear where your diagnosis stands - - - are you stating that you have confirmed that there is one 4x speaker that is properly working and one that is not? The "very faint sound" notation sounds almost like it could be a description of this speaker when a corroded pot cuts out all of the tweeter output, but this alone would not result in "no bass". My original suspicion was that perhaps the two speakers were wired to the amplifier inconsistently, which often results in deficient LF output. The issue mentioned about the tweeter cones is always worth inspecting - - this is a fairly common occurrence with this tweeter (see pic) and a relatively simple repair. Also, you should know that it is very typical for the original capacitors and potentiometers in these speakers to require inspection, maintenance, and/or likely replacement. If you have confirmed that there is one problem speaker and that wiring has been traced correctly, you'll probably need to dig further into the problem cabinet. Plenty of experienced members here can walk you through diagnostic steps, and it is very often useful to post pics of your speakers (keep pics to no more than 100KB in jpeg file format).

Hello Swilli, and welcome to the CSP forum. Hard to tell what's going on yet, but it sounds too early to place any blame with the speaker - - - you really need to identify and isolate the source of the problem. Are you certain that this second receiver is "reliable" and that both channels are functioning properly? Have you double-checked the wiring connections between components? Also, try swapping the two speakers (move B channel speaker to the A channel, and vice versa) and see what happens. This simple test might tell you if the "problem" follows the speaker, or it stays with the receiver's particular output channel. Those Pioneer SX receivers were very popular products, and a properly working 535 should be a nice match with the 4x's.

Thanks for reporting this difference - - it pretty much confirms what might be expected using the more recent and sensitive tweeter (038), and good to know that the switch is able to provide sufficient compensation. Happy to hear that this all worked out.

Although not a user manual, these bits are part of a four-page Teledyne brochure from 1980 for AR High Tech Speakers (AR-93 and 94), which does acknowledge that these floor-standers are related to the AR-9 lineup. I particularly like the section view, but the text is very good, too.

Hi yossaray, I'm not sure I know exactly what you're asking, but here's some additional thoughts. Also, I've done at least one other restoration of AR-6's using this same woofer, so let me know if you need additional pics. I'm including a couple pics from the most recent restoration. For removing the foam residue on the outer ring, I probably used a combination of this chisel-shaped knife blade (lower one) and some light abrasive paper. Just work slowly and carefully so as not to damage. Same for the outer rim of the paper cone - - no blades probably required here but this residue can be cleaned mostly with fingers and maybe light sandpaper. You want clean surfaces for all new foam glue lines. About those tweeters, they "look" to be in fine shape but first you'll need to determine if they are functional. Assuming they are, then you've got the decision about the pots. You can disassemble and inspect, and then decide whether to try to clean and restore the pots or as JKent has suggested, replace with new, inexpensive L-pads. Just my opinion, but I find this particular pot-crossover particularly difficult to work with. This is mostly because of the coil wire and the very stiff short nichrome wire (resistor) soldered to the pot lugs, but also because you're trying to work inside a tight 8-inch woofer hole. About the "black", are you just referring to the front panels of the cabinets?

Great-looking speaker set-up, Chris, but I really want to know if that is the Three Stooges on your ancient television?

I can assure you it is not - - - currently, I have at least three set-ups in my home that are all using low wattage vintage receivers paired with one or two pairs of AR 8-inch two-way speakers. Your system is really fine - - - projecting back to the middle late 70's and that would be a pretty high end rig, in my book. Those components seem very well matched and the sound is excellent on that SRV song. In fact, that is the exact same tune that member GD70 has used to demo his restored AR-3's at one of our local meetings of gearheads.

Hi Martin, and welcome. I was going to suggest that the "E" might signify the Euro market, but England is an equally plausible explanation. Not sure if this schematic or parts list fully matches your pair, but there might be something helpful here. In the schematic, you can see that the 4uF cap is directly in line with the tweeter, and as Kent has already noted, this should be replaced at the same time. Many people find that film caps work well in this application and are also very affordable, but a 100uF film cap will be huge and expensive, so a simple electrolytic cap suits this purpose well and is easy on the budget. Edit: almost forgot to say that your re-foam looks good, but trying to get rid of the annoying dents in the tweeter caps can sometimes be a frustrating process.

There was some in-depth discussion about these tweeter options here in Kent's recent 3a restoration. http://www.classicspeakerpages.net/IP.Board/index.php?/topic/10638-another-ar-3a-restoration/ And for a pic of the wiring mentioned above, schematic is attached.

Thanks again, Roy, for another terrific write-up. Your re-build objectives are clearly stated; possible differences with Chris's re-builds are clarified; and the options to use new replacement tweeters are well summarized. Also, I appreciate the remarks about two speakers in use possibly masking the response variations within a tweeter pair; and again, your advice to repair (or replace) tweeters in pairs rather than singly is always a helpful reminder. The reject barrel bin comment gave me a chuckle, and I enjoy the personalized anecdotes. I agree with you both about those high frequencies - - the oxygen gets pretty thin at that altitude. On top of that, many of us suffer from the typical aging male syndrome of gradually diminished hearing loss, particularly in the HF spectrum. With respect to the high 5000 Hz crossover frequency for this tweeter, it is worthy to note that in the subsequent top AR models, this x-o point increased to 7000 Hz in the four-ways (AR-9, 90) and 7500 Hz in the three-ways (AR-91, 92, 58s) with the newer ferrofluid tweeters. While the newer midrange (or upper mid) driver was able to extend up to this range, it is interesting to note this division of frequencies among drivers resulting in an even smaller work load for the uppermost driver.

Hi, yossaray, and in addition to JKent, I'll offer a second welcome to you to this forum. Not sure where you are located, but the European origin of your speakers is suggested by several clues: the printed labels (duh!); the slimline profile at cabinet perimeter; the multi-color fiberfill stuffing; and the painted cabinet backsides. Those speakers are fully restorable and deserve the necessary attention, but there is one thing that stands out with your pair. I cannot recall ever seeing this before, but your particular pair seems to combine equal aspects of commonly known versions AR-6 ver. A and AR-6 ver. B. All of the in-box crossover components are clearly version A, but that specific woofer and its attached capacitor (24uF?) and resistor (10 ohm?) are unique to version B. Your hybrids have seven components in each crossover circuit: two coils, two caps, two resistors, and one potentiometer. I would suspect that once restored, these speakers will indeed sound terrific, but this evidence seems to confirm that the piggyback cap and resistor accompany this particular woofer wherever it travels, and I think it has only been found in the AR-6. About that woofer ring. If you look closely, you'll see that a similar ring is present under the spider - see pic attached. The lower spider ring is durable hardboard, but the upper basket ring is more like a compressed cardboard that can be easily damaged. If this does happen, just build up the surface again with glue or epoxy or any compound that can be sanded smooth prior to foam install. The added dimension that this ring provides enables the woofer to reach its outermost extension and thereby maximize its LF capabilities. Also attached is before-after pic of my pair of ver. B AR-6 speakers, which use the same woofer as yours. It is worth the effort to restore these, and the work and results will be satisfying.

Thanks, Roy, for the excellent response. That is a very educational brief summary regarding the varying outputs of these tweeters - - both original and re-built units - - as well the rationale and usefulness for the pot control in this circuit. Thinking about this over the past few days, I started asking myself: Is it possible that I have not listened to these tweeters in their "fresh" state in 45 years or so, ever since a couple well-heeled friends of mine purchased new AR-3a's back in early-mid 1970's? I know I've heard plenty of "tired" 3/4" tweeters, and I still have no personal experience with any of the recent re-built variety or the Midwest replacement driver. Please correct any misinterpretations here - - but if I understand your statements, it sounds like you and Chris employ somewhat different steps and/or techniques in your reconstruction efforts and, in fact, do not have fully identical benchmarks for output of the rebuilt tweeter. Your process results in a reconfigured tweeter which works best with the pot set to max, as discussed in Kent's project; and Chris's tweeter possibly delivers a bit more HF energy and might sound best with the pot dialed back a bit. Am I beginning to get this right? Either way, it is good to know that we have several options to save or replace these aging drivers, and we doff our hats to you both for carving this new path. The remark about the number of variables involved with the new foam suspension blobs clearly suggests the challenge of the re-build process and explains the difficulty in achieving consistent results. (The statement about the AR manufacturing "nightmare" immediately brought to mind that 60's AR advertisement which showed barrels full of rejected drivers in the old Cambridge facility.) What is most surprising, however, is that despite the challenge of the initial manufacturing process to produce tweeters with consistent response performance, this driver was assigned high-profile duty in two of AR's biggest Classic sellers - - the 2ax and 3a - - as well as several other top line models (AR-5, LST/2, and LST). The reviews were great, if I remember correctly, but one wonders what/where was the level of corporate confidence regarding longevity? My suspicion is that - - much like the new-fangled urethane polymer (foam) surrounds - - no one really knew how to predict a meaningful lifespan. This discussion is tempting me to tear into my 2ax speakers later this summer at the same time when I assist my friend with his 3a's, and I assume I will follow Kent's procedures for diagnosing these tweeters after removal from their cabinets. And this brings up another question: exactly what are the physical differences between the 4-ohm and 8-ohm versions of this tweeter, and what should one look for if examining a pair of each simultaneously? Kent - - once again, your restoration project here is terrific - - but like many threads, spurs are created which must be explored.

Do not scrape off that mystery ring that you've uncovered - - it is essential for a proper foam installation. You have a very nice (and unique!) pair of Euro-assembled AR-6's. Will comment further as time avails - - am on the run again today.

The Library section on this website offers some very good information regarding your dual dome driver - - I believe this is part no. 200048 that employs the singular shared magnet structure. A low-resolution copy of the drawing for this driver(s) is attached which includes detailed assembly notes, but there is also a separate document regarding performance specs not shown here. A few portion of blow-ups are shown FYI, too. I think Stimpy makes a good suggestion here, but there are other drivers that might also be suitable parts donors. A quick look suggest that the tweeters from the AR-58s or the AR-9/90/91/92 series have similar construction - - the outer dome and underlying wood button are identical parts numbers ,but the voice coil/surround part number might be different. I suppose this might difference have an affect on performance, but it appears these parts should "fit".