tysontom

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  1. The Beautiful AR-3

    Those AR-3s look great with the black grill! That is a unusual rocking chair, obviously hand-made! --Tom Tyson One interesting thing about the AR-3's grills is the ability to see a faint image of the midrange and super-tweeter through the grill. I always thought this was a great look. Picture from January 1, 1963, showing an AR dealer demonstrating speakers to a customer (and multiple other lines, such as Electro-Voice, JansZenand University). I think this was one of the many New York City hifi dealerships that were around the area that eventually became the site of the ill-fated Twin Towers. These dealerships vanished as the city authority bought up the land in that area to build the towers. --Tom Tyson --Tom Tyson
  2. The Beautiful AR-3

    Those are beautiful AR-3 speakers, and as you note above, the cabinets are the "AR-3a-style" front molding. That is, AR began to build AR-3s in the late 1960s, after the AR-3a was introduced in 1967, using the new-style molding with USM hot-melt glue holding the grill frames in place. However, the AR-3 grill material is more difficult (it doesn't stretch) to attach to the AR-3a-type grill frame, and it causes some slight sagging if too much pressure is applied when attaching the material. There is also the tell-tale gap around the edges. Nevertheless, the end result is always very handsome. --Tom Tyson
  3. The Beautiful AR-3

    You could not have picked a better "AR" person than Minh when you got these AR-3 speakers! Minh is a perfectionist and an expert regarding AR speakers, especially the AR-LST, AR-3a and the Mark Levinson LST the "Avanti." I think Minh is somewhat less active in the historical/restoration part of AR now, as he is very busy raising his family. Those AR-3s are very handsome and I think well-placed in that room, placed at the correct minimum height off the floor to prevent boominess. With the left channel fairly close to the corner, I suspect the bass is quite powerful! I see the right-front corner of a pair of AR-LSTs barely in the picture. --Tom Tyson
  4. The Beautiful AR-3

    That is great! Virgil Thompson, one of America's all-time leading composers and music critics, used AR-3 speakers for many years until he replaced the 3s with AR-3as, shown in this great ad. His reflection is shown in the mirror in this ad just as it was in the other ad! Note, too, that AR began using this slightly different "AR" logo with the black square background. This started around this period. It is very interesting that AR never paid anyone for an ad of this sort. These were done gratis by the artists, but of course, the speakers were provided at cost to the artists. This started back in the 1950s, and this tradition remained until the mid-1970s, I believe. Insofar as AR was a very prestigious and highly regarded brand, the artists typically felt good about doing the ads for free. Even Miles Davis and "Satchmo" were never paid for doing ads for AR! --Tom Tyson
  5. The Beautiful AR-3

    It would be great to see many of the AR-3s that are in collections among members of the CSP! Here is an AR ad from 1965 showing radio station WTFM in New York (many recording studios and radio stations used AR-3 speakers) and the domestic installation of American composer and music critic, Virgil Thompson, showing AR-3 speakers with the proper orientation of the "3" brass stick pin. There's no hard and fast rule about positioning the "3"pin, but the way AR positioned it was in the lower-right corner opposite from the "AR" brass logo plate at the woofer end. Typically, the pin is straight up-and-down when the speaker is located horizontally, even if the speaker is mounted vertically. Since the midrange and tweeter are more nearly vertically aligned when the speaker is mounted horizontally (as in these examples here), the dispersion in the horizontal plane is not affected, but the vertical dispersion is somewhat attenuated, reducing floor and ceiling bounce. In hard-cold actuality, it makes little difference since the sound is predominantly reverberant and "blended" by the time it reaches the listener's ears, once back 5 or 6 feet or so. --Tom Tyson
  6. Korina Korina

    "Here is what I came home with. Much nicer than I thought they would be. AR discontinued the Korina finish in 1965." No, korina veneerwas was discontinued before theend of 1964. This wood veneer was never available in any of the 1965 AR models. I don't even think it could be special-ordered. --Tom Tyson
  7. Korina Korina

    Those are very beautiful AR-2as! Lacquered korina is such a beautiful wood, andthat finish was very seldom ordered, so the speakers are fairly rare and certainly worth holding onto. These speakers were originally returned to the factory for the $15.00 upgrade to the newer CTS/AR midrange dfriver. The original grill cloth material was different (this is the 1965 and later beige linen), so if you did anything, you might want to go back to get the original-type grill material. You will also need the square AR logo and the "a" pin on the opposite end. I wouldn't try to go back to the two 5-inch AR/Carbonneau midrange drivers, as the updated 3.5-inch midrange is vastly superior. Are both speakers finished on all four sides? Usually, AR did not finish the AR-2-series on the bottom, long dimension. It was usually placed on a bookshelf, but with this finish, it's possible that all four panels were done in korina. Congratulations! --Tom Tyson
  8. The Beautiful AR-3

    I know of no other loudspeaker that is more beautiful than the AR-3, that is, in my opinion! I sent this pair to the San Francisco Museum for the Dolby-sponsored "History of Audio" display a few years ago. This pair of early 1960's lacquered-mahogany AR-3 speakers, C 78XX, shows the absolute beauty of the AR-3 cabinet, grill and logo placement. Notice that the logos are properly placed on these speakers and the gold thread in the ivory saran grill material (saran is a Dow Chemical PVDC material very similar to nylon) is evident in this early version. The gold thread was discontinued a few years later. These speakers demonstrate the natural look of lacquered-mahogany cabinets -- a satin luster --and it is very rare to have a pair survive for over 55 years in this condition, but this pair was always pampered and well-kept in air-condition space and storage. This pair has never had the grills removed, but fortunately,this pair also has strong, cleanmidrange and treble output, a very desirable thing for an old AR-3! The level controls have oxidized, but occasional rotation back and forth cleans the contact surfaces sufficient to keep good output. Send pictures of your AR-3 installations and give a description of the sound! AR-3 lacquered-mahogany mounted in office bookshelf with AR-3a (oiled-walnut finish) below. Note the satin luster (not a high-gloss luster) of the lacquered-mahogany finish, sort of a piano-lacquer finish. Note, also, the position of the "3" logo, properly placed, though it should technically be one more verticallevel to the right, a bit closer to the molding. Gold thread woven into the saran grill material. --Tom Tyson
  9. AR 3 toe in or not?

    Now there's a setup! I am amazed that sound actually comes out of the AR-3a system being driven by the Pioneer SA-508 (the American version was the 5800), as that amp was designed to produce 25 watts/ch into 8-ohm loads! The 3a will tax any 25-watt amp, and the speaker's impedance runs solidly in the 4-ohm territory across the board! Low in sensitivity, big in current-draw and hard on amps is the AR-3a's credo.It is therefore a testimony to the Pioneer's excellent design that it even drives the AR-3a at all! Otherwise, I'll bet the sound in good in that room! (No additional charge for this message). --Tom Tyson
  10. AR 3 toe in or not?

    Thanks, Carl. It is an academic discussion, butthere are any number of explanations for the response rolling off earlier in your measurements, but it's mostly related to the radiation angle, bass reinforcement in the listening room, andmethod in which the speaker was tested. The speaker's actual Q could be off somewhat; the compliance of the newly rebuilt woofer might have changed from the original, and so forth. Also, If your speaker ispulled out into the room, as you explained, it is to be expected that the response will be attenuated sooner due to the larger radiation angle as I discussed in my message above showing the, so your tests are certainly valid when measured in that method. Any direct-radiator speaker will actually begin to roll off at a frequency just above the resonance frequency, so when you see the AR-3a woofer beginning to roll off around 50 Hz, that is correct even for the perfect, flush-with-the-ground 2π measurement technique. It might be interesting -- if not a total pain in the tail -- for you to actually calibrate your test setup by measuring an AR woofer flush with the ground with the microphone at about 1 meter to see if you can replicate the standard measurements. This way, you have quantified your measurement technique for a different position, and you will know that if your measurements are close to the original ones done. --Tom
  11. AR 3 toe in or not?

    Hi Carl, Thanks for your comments on the 180˚ solid-angle method of testing speakers. Good message. If you look closely at the AR woofer 2π frequency response, there is a slight rise (1.5 dB) just above resonance (43 Hz), but the response crosses the 0 dB point almost exactly at resonance, precisely as it is supposed to do. You noted the "50 Hz" point, at which the overall response begins to fall off, but that is the point 1.5 dB above the 0 reference level. Also, the woofer is almost exactly 12 dB down at 20 Hz, also exactly as it is supposed to do. It has nothing to do with it being 10 Hz above box resonance. The Q of 1.0 means that the speaker—when measured facing into a solid angle of 180˚—will be flat down to the point of resonance with the 1.0-1.5 dB rise at a point just above resonance, and the AR woofer responds precisely and predictably in this manner, one of the great attributes of this remarkable woofer. Also important is that there is no ringing or "overhang" in the response at resonance with the AR woofer with a Q of 1.0but only a very very slight rise just above the resonance frequency (fc). The mistake that is commonly made, that of measuring a woofer facing into a 360˚ solid angle (technically, suspending the speaker in the middle of a room away from all boundaries), means that a speaker has poorer coupling to the air and will begin to roll off in frequency at a point below the frequency of ultimate-radiation impedance (air-load resistance) , around 600-800 Hz for the 12-inch woofer in the AR-3a, down to resonance, but not below that point. In other words, by increasing the solid angle from 180 to 360, the response is cut in half below the air-load resistance frequency. Since no one listens to a speaker looking into 360˚, but rather at solid angles of 180˚, more or less, it is appropriate that the speaker's performance is quantified at 180˚. Therefore, at 180˚, the AR woofer response is essentially flat down to resonance. However, the room itself increases bass down at and below resonance through the effect of the so-called "room gain," so the effect is a slight increase in bass down to below 40 Hz, sometime "room gain" will increase bass down to 30 Hz and below without equalization. When you pull the speaker out from the wall to measure it in a room, you are getting the solid-angle reinforcement of the floor, thus accounting for some increase in output from a purely 360˚ measurement. 1. An AR-3 measured at a solid angle of 360˚ in Harvard University's huge anechoic chamber. Note the gradual decline in output below air-load resistance down to resonance. By the way, mounting an AR-3a on a stand above the floor, back against the front wall, will give at least as flat a bass output (probably more room gain) than mounting in a bookshelf. So the bookshelf-mounting of the speaker does not increase or enhance bass output, but it tends to eliminate the unevenness associated with the boundary "dip" described by Roy Allison. —Tom Tyson
  12. AR 3 toe in or not?

    It is a bit confusing, but the front wall is the wall where the speakers are located, facing towards you. The back wall is at the opposite end of the room from the speakers. The front face of the speaker is the grill side, but it looks at the "back" wall. I guess it is a matter of interpretation, but that's generally the correct definition. So, yes, the back of the speaker should be a few inches from that wall. It is not a critical dimension, but the AR-3a, and most AR speakers, are designed to be placed close to the "front" wall. Sorry that it is confusing, but I think you understand what I'm saying. --Tom Tyson
  13. AR 3 toe in or not?

    The idea is to have the front face of the speaker flush with the wall. If on stands, they should be back within a few inches of the front wall anyway, but the depth of the cabinet, front-to-back,will cause sound waves at certain frequencies to travelaround the sides and bottom of the speaker, bounce back out-of-phase with the front wave, causing a cancellation (or "dip") at certain frequencies. Again, there is argument as to how much this is audible, but it's there nevertheless. This is what the Allison speakers were all about. Flush in a bookshelf, however, there is none of that. You can put them on the floor, and that will cancel the reflection off the bottom side of the cabinet, reducing the "dip" effect,but an AR-3 or AR-3a will sound boomy or tubby if placed directly on the floor, so this is never a good placement. On stands, close to the front wall, is second best to flush-mounting. Typically, one speaker on a stand (the left or right channel) should be somewhat closer to a side wallthan the other, and the speakers should be a minimum of 12-15" inches off the floor. This so-called "Allison Dip" has actually been known for many years, but Roy Allison and Robert Berkovitz actually quantified and defined the effect during his test of many AR-3as used in homes (and the AR Rooms) around the Boston area, and Allison and Robert Berkovitz wrote a brilliant paper describing this in several papers, the most notable and detailed was the October, 1970 JAES paper, "The Sound Field in Home Listening Rooms." This is a long detailed paper with millions of graphs and representations, but it is worthwhile to read at some point. Top picture is actually an AR-3 being measured facing into a 180-degree solid angle. Note the lack of any interference or reflection in the bass output right down to the resonance frequency, shown in the measurement of that speaker. This is considered an exceptionally uniform, flat response for a woofer. --Tom Tyson
  14. AR 3 toe in or not?

    Bookshelf mounting for the AR-3/AR-3a is certainly an ideal way to do it if possible. It most importantly avoids the so-called "Allison Effect," or boundary dip where the woofer's output at certain frequencies (usually in the 300 Hz range for the 3a) will tend to bounce off the floor and back wall and come back and "cancel" the bass energy at that frequency. It's not nearly as serious as some would have you believe, and many manufacturers have simply ignored it for many years, but it is definitely a measurable part of the frequency response in the low frequencies. Mounted flush in a bookshelf or flush in a wall, etc., gives a nearly ideal, flat output as the speaker faces a true 180-degree (2 pi steradians) solid angle, without any dips or peaks. Since the AR-3/3a woofer is literally flat within 1.5 dB from 38-1000 Hz, the low frequency is very uniform when a speaker is placed in a bookshelf. But is the dip that audible? It is audible, but you usually have to be listening to white noise or have a A-B comparison to realize the difference in many cases. Some Allison audiophiles insist that the "dip" is extremely important, but there are other opinions. With the dispersion of the AR-3 and AR-3a (and even more so with something like the AR-LST), once you are about 3-4 feet back from the speaker, the bulk of the energy that reaches your ears will be reflected, not direct. In other words, if you want to listen to just the speaker itself, as though anechoic, you have to be right in front of it within a foot or so, and you could then toe-in the speakers. Otherwise, it is not necessary. My earlier AR-3a bookshelf mounting (below) was good, but I had to add more books around the speakers to the sides and below, to make it more of a flush setup. --Tom Tyson
  15. AR 3 toe in or not?

    AR never recommended "toeing-in" AR-3s or AR-3as or any AR speakers, mainly because these were designed to produce a widely dispersed, enveloping sound field. Some speakers are very directional, and these benefit somewhat by having them pointed in the direction of the listener, but this would not be the case for an AR-3 or AR-3a. Usually, the speakers that are very directional (poor dispersion throughout the midrange and treble frequencies) will sound poor back in the reverberant sound field because the "power response," or the combined acoustic-power output into the room, is greatly diminished. What you should hear in a room (unless you are at point-blank range) is a combination of direct and reflected energy (much more of the latter), and the better the dispersion, the smoother and more "spacious" (and realistic) the sound will be. On the other hand, directional speakers lack the 3-dimensional sound of wide-dispersion speakers, and directional speakers will sound dull well back in a room because of the attenuated reflected energy. --Tom Tyson