Giorgio AR

Ra.ra, I confirm the switch with a plastic lever and also the 90 ° rotation of the crossover panel. The rear-wired tweeters have the same diameter magnet as the previous ones, subsequently they got the denomination 200005. Between the three couples, there are differences in the grilles frames (in the older couple the frame is in wooden strips, the other two have a masonite frame with different cut) and in the linen texture.

Ra.ra below you can find photos of the third pair of AR7, recently purchased, is the second assembled in Holland, completely original and untouched, unlike the two previous couples it is a late model with vinyl coating (the other 2 couples are covered in wood ), this one as well as the others has consecutive numbers on the labels. The last photo shows the three AR7s together.

Ra.ra, you are always helpful in your posts, today I finished and closed after the repairs of the cabinet and replacement of the capacitors (in the older AR4x pair a woofer still has small leaks in the seal, tomorrow even this small problem will be fixed ) both pairs. I checked my photographic archive and I attach the labels of the second pair of ar7, in which the letter H is written correctly, from a survey with my family, it should be an M prefix, I hope that over time they will be found other testimonies on the existence of this prefix (as previously written, from certain news, AR speakers were assembled in Italy in the 70s as well). In the attached thread I add the photos of my recent acquisition of the third pair of AR7!

I purchased my second pair of AR4x, like the previous one, this too is of late production (the first pair is around the end of '69: the date imprinted on the woofers' magnets is 69-46 and 69-47, no other date 'interior of the cabinets; in these woofers there is a damping ring on the cone around the dustcaps), the new pair, has date on the magnets of woofers 71-01 and 71-08, in a cabinet there is a stamp with date 06-71. The veneers of both should be walnut, but darker than usual (the shades differ slightly, however dark). The strangest aspect for me are the progressive numbers on the back labels: the suffix indicating the model (FX usually) is preceded in both pairs by the letter M (MFX) and the progressive numbers are: 006195 / 0075xx the first couple 022415/022680 the second pair If they had been assembled in the USA, probably the number on the labels should have been around 300000/380000, the letter preceding the abbreviation identifying the model should indicate the country of assembly (e.g. H = Holland, E or EA = England, AU = Australia), I wonder if it is possible to establish where my two couples were assembled (perhaps in Italy? Here at us, from certain news numerous AR speakers have been assembled, including replicas in the 90s of the AR10PII of which I have a couple !). In addition, this numbering difference, I had already noticed in other AR speakers, as late specimens of AR3a and AR7, this in my opinion makes me think that more speakers have been produced than reported by the US numbering !! I hope to stimulate further research and information on AR speakers labels with different numbers compared to the normal USA chronology. In addition to the photos of the two couples, I also include photos of the original capacitors (wax box in the older AR4x pair, with values very out of specification , almost 40uF, the Sprague capacitors are still within tolerances, however I have replaced all the capacitors, all now very close to the 20uF of the project (these photos are to satisfy Ra.ra's knowledge, always very careful on the types and values of the original capacitors AR speakers !!). In both pairs, the woofer seat (the baffle is in chipboard) with sealant gasket, was cracked laterally and was restored by gluing the fractures with two-component glue to guarantee the original seal of the air suspension. Above the older couple '69 pair ù Up '71 pair '69 labels up, '71 down '69 capacitors '69 new capacitors '71 new capacitor '71 Sprague capacitors (values painted in black up) Date on '71 cabinet '69 woofers '71 woofers '

If you lift the edge of the foam, and you can help yourself with a spatula, screwdriver, card or other atraumatic objects (take advantage to also check the foam nearby, even here continue the gluing), clean the metal and the portion of the ring, also put the glue that was discussed above, wait for the time of gluing and pressing occasionally the gluing area with the fingers to ensure excellent adhesion. The foam will return to adhere to the whole circumference as it was originally. Also check the other woofer and do the same job if necessary as the first one. Giorgio

On left original AS-2a masonite panel Perform all the holes in the same position and diameter New panel with writings and mounted pots Back side AS-2a with original masonite AS-2a back side with reconstructed masonite

Hi Teknofossil, DonT long ago published on my request the AR3-st scheme, under the photos You find the thread by typing: original AR paperwork I have! I also used AR-1MS to make a medium / high section only to the AR2 woofer (I still have to attenuate the small AR-1MS with appropriate resistances!), Find the thread in the Mods section (moved there by moderator Genek!) Under the title: AR-2t I hope I've been helpful Giorgio

Another great piece to understand AR mids, this paper explains in a simple way the evolution, the "universality", the versatility and the greatness of this wonderful instrument, and also because, to date, in the form of a replica more or less equal to the original keeps its charm intact.

P.S: regarding the use of the Midwest midrange, here are the photos of a good use that has been made of this component, the photos have been taken from the auction site.

Hi ra.ra, first of all, in this mid, there is only the presence of the double paper adhesive on the outside of the flange, then if you look at the dome of the mid, after removing the plastic horn, around you see a glue ring transparent often with the shape of the inner ring of the plastic horn that pressed over it impressing the shape: at that point the plastic horn was not glued, adhered only (I think it was left to harden the glue until a certain time to thicken the dome fabric and then later flattened by the addition of the platic horn to perfectly seal the two flanges. Secondly, I have a wife who works in a dental office and brings me the tools that are no longer in use (because they are old or no longer perfectly functional for the original work), so old spatulas, hooks and special pliers. The beauty of these instruments is the fact that they end up slightly rounded, so they do not scratch or engrave metal, plastic or anything else. I am attaching photos of some spatulas (these are also very useful for refoaming both to remove the foam from the cone, and to remove it from the metal basket), the instrument below (and in particular) is a small retractor and is phenomenal for: removing the speakers from the baffle, special ones those with sealant like gaskets without ruining anything, and to remove the glued grilles (using the longest side), paired with other spatulas to help! Giorgio

Done! First I heated the mid at around 40 ° C, then with the dentist's instrument, a small atraumatic spatula, I raised and unglued the double-sided adhesive frame that unites the plastic horn to the mid flange (I think it is the same type used on the AR10 late tweeter and AR11 with the upper foam ring!). I also measured the thickness of the paper which is 0.2 mm. Total time for removal (except the additional 20 min. For heating the mid) about 2/3 minutes. Thank you ra.ra, and I hope this work is useful to the enthusiasts! AR. Here below the sequence and details

Ra.ra, rereading yours first answer, apart from the classification, the reported differences between the various types of mids useful to clarify the correct use in the speakers that need to replace mid units, I have thought about your statement that RoyC has removed from one of these mid the plastic horn! I could have done the same and then replaced the two types of plastic horns, it's too late, but now I am going to remove this detail from my 200044 with the broken magnet. Then I will publish the photos of the removal works and the separate components. Thanks for the great input Giorgio

Thanks IARrybody, splendid work, thanks for the report on the comparison of the listening between 2 speakers similar but not equal (before / after changes simultaneously). I really appreciate the use you have made of quality bipolar electrolytic capacitors (up to now I used expensive and large polyester), I am more and more convinced to use this type of capacitors myself! Since you've handled both AR3a and AR11 lately, I renew to you the request to listen to your renewed and improved AR58 with mids and tweeters both at -6db and another step at -3db, I ask you this because you have the chance to soften the range medium high and the reason why I want to make the same change to my AR58 is to be able to make them sound similar to AR3a (certainly not the same for many reasons, but I want to bring all my 12" speakers closer to the AR3a specifications). Thanks to your help, I can first know the result that I can get with your change.

Really a good job, excellent excision and brilliant intuition to replace the crossover board from AR58 to AR91. This is something that I would like to do too with my AR58s in which I find the mid / high range too intrusive (although this was probably wanted by AR technicians to adapt the sound to the request and conform to other producers of the time) . I think that I will not replace the crossover boards, too difficult to find in Italy and too expensive to buy from the USA (burdened by production, customs and taxes!), But as soon as I find two pairs of three-way switches appropriate, there will be on original crossover the only addition of switches and resistors. IARrybody I ask you if after a break-in period you can make a report with listening to the switches: -6 db mid, -6db tw and also -6 db mid and -3 db tw. Also if you can compare these 2 types of adjustments with AR3a pair with the settings of the pots as per the AR specifications (3.25 ohm mid. - 1.75 ohm tw.), In my opinion your AR58 improved should approach in the overall performance at "old" sisters! I hope for one of your reports that I would like very much and I think it is also useful for many other enthusiasts who want to make AR58 more flexible. Last thing, you said you put the TNG woofers to rest, the last picture seems to show a TNG woofer on the left and an AR woofer on the right: is the photo before the change? Giorgio

Perfect Lance, I think the midwoofer no longer needs anything, just to work with his brothers and give you the sound that only AR9 can emit without any distortion! Good listening Giorgio

Hi Lance, congratulations for your AR9, they will give you great satisfactions and it seems right that besides replacing the capacitors of the crossovers (check if you can also all the other resiatenze values, coils and switches), also restores the 4 woofers and the two midwoofers. Regarding the wire lead flexibile, in the last photo it seems to see that the welding is not flat and similar to that of the negative contact, perhaps it was an intervention performed by the previous owner or a technician (when you found the dustcap partially detached, probably you could have raised or detached it further to see if there was any repair on the top of the cone where the wires run!). What you did: releasing the natural oscillation of the cone is right and if you have solved the problem as you reported, I think you should no longer intervene (just check that the wire braid is intact). Regarding the foam, finding the original is no longer possible and I am sure that on CSP you will find many tips on the most suitable surround foam, furthermore due to the fact that this woofer is used in AR9 as a midwoofer, I think that even if the one currently in use does not were the most correct, this does not significantly affect the sound of the speaker correctly; however here there are several experts and happy owners of AR9 who will be able to help you! I wish you good listening Giorgio

Jeff, your instructions are like the AR3a-IMPROVED, in the sense that it improves and increases the information, in fact it suggests to first drill the wall horizontally and then continue to insert the nail diagonally, thank you for giving me additional information! Giorgio

Finally purchased and arrived today at my house a kit of Wall mounting AR-7 speaker system. It consists of an instruction sheet and a small envelope containing 4 brackets to be fixed to the back of the speakers, 4 bracket fixing screws (and I think then added the 4 brackets and wall nails on which to hook the speakers). The instruction sheet, compared to what I have already seen previously published on CSP, specific to AR4x, is updated for use with AR-4xa, AR-6 and AR-7 systems, as written on the Note and I think this is the only difference compared to previous kits. Below the photos on the instruction sheet, as well as the brackets, the screws and the small envelope containing the hardware. Thanks to this desired kit, I will finally be able to place a couple of my AR7s on the wall using the original material supplied by mom Acoustic Research !! Giorgio Instructions Hardware As last, another sheet of: power handling ability and power fusing information

I think it can be a black paint on the masonite

Hi Budney agree that the mids are not proper to the AR3a improved, but they should be (and the photo you have attached with the visible midrange magnet that also has the label indicating the No. 200010-1 near the positive pole) indicates a component made in the USA, probably born for AR10 or AR11 "second series" with silver screen. This mid is not Tonegen. The correct tweeters should be the ones you see in the picture below, just photographed to show them to you! In addition I also send you the photo, always performed now of a mid Tonegen of my AR10PI Replica and finally 3 medium my: 2 front wired, a wired back of AR3a imp / AR3a / AR10 / AR11 (clearly the only mid back wired is for AR10 / 11, but it is also on AR3a / AR3a imp !!)

Hi Frank, it was a dream, the purchase of the cabinets, in which I saw myself sitting on a throne formed by 6 or 8 cabinets! Then 20 others remained erected to the wall as a defense of my house. I live in an old two-story 1860 house, but they are about 50 square meters per floor and having 18 pairs of Acoustic Research speakers I have already erected more than one wall composed of speakers. I have to stop with my collection (composed not only of AR, but also of other 12 pairs of speakers and various electronics). You have two or three pairs of AR LST and AR90 and AR3a if I'm not mistaken, but I saw a listening room with an eye wall of about 10 meters and I think that only that room is as big as my whole house, you said of have several 12 "spare woofers and as many tweeters! That's right, I too have collected many spare speakers that are now in my closet to rest (last purchase yesterday, a 12" early ceramic woofer from AR3a that I liked because his way is particular and I am attaching the photos); let us return to the dreams of the beginning of the post, but this is more concrete and it is the desire to build me some replicas of AR3a (the shape of a parallelepiped lends itself to being stacked occupying the least possible space), perhaps even AR11. This is achievable (I would have also tried to buy AR3a cabinets in the USA, now there are some nice cabinets for sale, but to have a pair at my house, the purchase burdened with shipping, customs and taxes is often too expensive for me), clearly not in the short term, but you'll see that within a few years, I'll succeed in the enterprise. I think you know that I have a pair of AR LST (I have to change the surround foam for two years), but once they are operational I wouldn't find a proper placement for them in my house, or I would have to revolutionize a wall in my house by building a solid shelving on more plans to be able to insert as many AR speakers as in a bookstore! We will see over time what I will do ... I would have bought this too, very early ceramic woofer, but then I should have found the brother: very difficult and I decided to buy only the woofer above Frank, I wish you good listening in your splendid and great hall Giorgio

Thanks, views and open already post: If I were in England, the cabinets would already be at my house, if you live there, buy them and distribute them to us enthusiasts at the right price! Ciao Giorgio, Under the post

Hi AL, the correct AR38s woofers are with number on the basket: 200040-0 are given for 8 ohms (I measured about 7 my 200040 woofers with values between 6,1 and 6,7 ohms on my instrument) and are used on many AR speakers: AR38s, AR48s, AR48b and others, so they are easy to find, be careful that the foam must originally be under the paper cone. The 200033 woofers are 4 ohm (the magnet is also different: round and not square, heavier) and are certainly AR92 and other AR speakers, I have now measured a pair in my possession and have a resistance of 3.5 ohms both . You will surely get other answers and suggestions, but I think that for a temporary listening (waiting to find a pair of correct woofers) the 200033 currently on your AR38s are also fine. I am attaching a photo in which of the AR92s that should have the 200033 woofer, all have 200040 8 ohm woofers (the 3 woofers you see are of the same type 200040, even if the woofer color of the upper AR92 is darker than those below ), later a couple will receive the original woofers (I have to refoaming the original woofers), the other pair will stay with the 8 ohm woofers and we will see the difference between the two pairs! Then below I am attaching the photos of the pair of 200033 woofers, the back of the 200040 woofers, the same in the front view of my AR48s, the ones that are now in the lower pair of AR92 !!

Ra.ra, I found my old post, including the Tunedguy! Response, below the post.

Wellcome Joe very beautiful: original packaging, real wood veneer, Aetna pot on the back, should have front wired tweeters, early production number, minimal aesthetic defects on the veneer. In the beautiful photo shoot you have attached, there are no photos without the grilles, which on these early specimens are glued to the front baffle (if you don't think you can take them off, make sure the woofers and tweeters are working properly), if you want to try to take them out the grilles, do not use screwdrivers or awls to avoid damaging the wood, but gently insert into the slot "grille / wood one or two spatulas of about 2/3 cm., starting near the corners and gently forcing the grill outwards, alternating below the angles to be forced a little at a time, then where there is the masonite beam between tweeter and woofer there are 2 additional gluing points, perform the same delicate forcing and you should remove the grille without damage to it and to the wooden frame In my opinion, on the scale of values they are positioned at the top. Regarding the actual value for the sale, check the famous auction site where they are currently sold with a price between $ 200 and $ 400 (though AR4xa are hardly sold at the proposed price!). I cannot value objects that are not mine and far from me, but the fact remains that your AR4xas are very beautiful and include excellent original packaging. You do the price and the buyer can make the proposal! In my opinion the AR4xa sound (if in order in all the components) very well and if these were mine, I would keep them for me !! Giorgio