I bought a pair of very well cared for 1965 early AR-2ax speakers from the original owner in Denver CO. Scratches in the finish, but in good shape. They’ve never been touched or molested. I haven’t yet refinished the cabinets. But I did document work on the *sound* of these, before, during, and after work. While the recordings aren’t “great,” I think there’s enough to give folks an idea of their sound. I replaced the capacitors in them. The level potentiometers were original and completely corrosion free, so they stayed. They work as a voltage divider to adjust levels of the tweeter and midrange. They aren’t L-pads. The woofers are perfect, the doped cloth surrounds are in perfect shape. Tweeters and mids are good. But…after replacing the caps, I still didn’t like the tweeters. So I rebuilt the original phenolic dome tweeters, to increase their output. Sound unmolested: Sound after replacing crossover capacitors: https://youtu.be/zxzn-5f95Io Sound after rebuilding both of the tweeters. 5 min 30 sec track from an original 1963 record of Dave Brubeck Quartet. You’ll get an idea of how the drums sound, cymbals, piano, sax. https://youtu.be/4IC_ceKwYjs
I envy your tenacity in dealing with these speakers. Most of the old consumer ones I've encountered have had blown tweeters and/or mid-range drivers. It's really difficult to get a handle on the sound of these speakers on a microphone pickup via a YouTube video, so I'll have to take your word for the improvement. Old AR speakers have withstood the test of time for a reason. They had a definite personality (that 'east coast sound') which worked extremely well for genres like classical and jazz. Rock....not so much....JBL and Cerwin Vega owned that space. AR's music room at Grand Central Station NY.
I've always considered the idea that AR's weren't good for rock to be a canard. My first pair of "good" speakers were AR-14's I bought new in 1977 and I listened to nothing but rock and they sounded flat fantastic to me on the 14's. Are my AR-9's good for rock? Don't even go there.
There are always exceptions - my main point though is that the AR midrange and tweeters were not robust enough to take the punishment of loud rock music continuously. That is why I made the commment about blown midrange and tweeters because of users who played music which the speakers weren't specifically designed to handle. JBL and other 'west coast' speakers were designed with the assumption that they would not be used most of the time with relatively benign string quartets. AR speakers were - that was the whole 'New England' thing. Early Wharfedale speakers were the same way - I have blown tweeters to show for that - the 6dB per octave crossover was super-accurate but super-fragile to tweeters.
Weren't the blown drivers largely the result of users not feeding sufficient power to the AR's? I knew people back in the '70s who were routinely blowing both tweeters and woofers from cranking their AR's far too hard with not enough power -- driving them into clipping.
Clipping damage would get right back to the playing of music which would be most likely to clip - rock. Clipping is not going to happen when playing a string quartet, or even full orchestral because these users generally wouldn't be likely to blast the SPLs. Rock music generally contains sustained lower frequency content (bass guitar, drums) which demands the most power from an amplifier and is most likely to make it clip. These were the target customers for AR speakers. Hardly headbangers. This is Cerwin Vega's public image. Eggheads need not apply.
I went to many concerts in the late 70s and early 80s. LOUD. I don’t know why anyone would want those SPLs in their home. So loud, you couldn’t distinguish distortion vs music. It’s at those levels that folks blow amps and drivers. Better off using white van specials. These 2ax speakers are rated at 91 dB, 1W/1m. Plenty loud for me. But I did go “out of the box” on redesigning the surrounds for these dome tweeters. Original factory in ‘65 had these tweeters operating below the SPL of the mids by 4-5 dB at 100% potentiometer setting. Mine operate at a nice higher level of output. On the last video, the cymbals were barely audible with the factory tweets, and both were in pristine condition. Here, you can clearly hear the cymbal strikes and overtones, where before it was just a smeared and muffled “shhhh” sound. AR was not operating them at full potential. Just one speaker, after tweeter rebuild:
With those sealed cabinets AR speakers produce a clear tuneful solid bass and the mid bass does not bleed into the midrange it's so tight. This makes their speakers sound correct in a lot of rooms-correct as general indicators of the sound-not as headbangers. That full tight midbass made up for the typical floor cancellation suffered by so many installs I have experienced in my years in the field. In other words they sound relaxed and full. Perfect for rock IF you use them with powerful non-clipping amplification! That bass and lower end! That SMOOTH clean sound! No ear fester like with honky sounding horns! No real limit to how loud you might like it! No piercing treble like with some West Coast designs! Their bookshelf designs were not adequate for truly large rooms but terrific in smaller ones! I was a big fan needless to say. My buddy Paul Ledford had a pair of the biggest ones-AR3a AND a pair of KLH Fives strapped on top of those. Powered by a pair of Mac 275 amps they killed in his somewhat limited space (Timothy Leary's old cabin in Coconut Grove). Hendrix could be FELT. Very nice! I can only offer congrats and thanks to the OP for keeping the flame alive. Good show!
The AR 9s ain't 4a, 2ax or 3a speakers so comparing your speakers to the original ARs is moot. My Dad owned AR 3a and I owned AR2ax speakers back in the day and yes they didn't reproduce rock music all that well and they were inefficient which was a problem when my Dad and I bought the speakers because 60WPC were considered 'powerful' amps back in the early '60s. I an embarrassed to say how many tweeters I blew when my amp clipped and blew them to smithereens. As a consequence I built my own speakers with the help of Mickey Rosenstein, a neighbor, who was an audio engineer at RCA. 2-12" bass guitar speakers, 1 midrange horn and 1 tweeter horn all by Utah and the best they had to offer - thanks Mickey for helping me and getting the drivers at such a low cost. They ROCKED and my neighbors knew it I had the band in my house - amazing what 104 dB efficient speakers can sound like with only 60 WPC!
Classic AR series speakers (AR-1 - AR-8) were designed with a step shaped response curve. The midrange level was -3db relative to the woofer, and the tweeter level an additional -3db down...a total of -6db relative to the woofer. However AR speakers had outstanding off axis response. AR speakers were not designed for near field listening; instead they were designed for a distance of 10-15ft from the listener to approximate a row 10-15 sonic perspective. At this distance a listener heard a combination of direct response, and reflected room response (remember the great off axis response referenced earlier) for a relatively well balanced complete sound. AR speakers were designed to reproduce human vocals and acoustic instruments. They were not designed for electric guitar and bass or rock music. AR began to loose market share as the 60's turned to the 70's, and buyers purchased speakers with "flatter" on axis response. AR introduced the AR-LST, then the AR 10pi/AR11, an finally the AR9. All were designed to deliver flat on axis FR, with high power handling capacity. Note that the LST achieved this by using multiple AR dome drivers because single drivers (as used in the AR 2-3-5) could not operate "flat" and loud for an extended period of time. The AR 10/11 used ferofluid cooled tweeters to achieve more output, and louder volume as did the AR9 which used a newer generation of dome drivers. I bring all of this up to provide perspective around the "classic AR sound" and to raise a question about boosting the output of an original AR large dome tweeter, 60yrs after it was manufactured. I am curious how the thread author rebuilt the tweeter, and if any steps were taken to protect the tweeter. Thanks.
Not when it comes to clipping them into blown tweeters and woofers. That's why I power them with a boatload of current. Common problem with my friends' AR's in the mid-1970s. I'd love if my 9's were somewhere near that efficient. However, back to the canard, I had a pair of the repro AR-3a's made especially for the Japanese market in 1989/1990 and I wish I still had them. I play some jazz and classical, but 90% of my listening is rock. They reproduced the music I like beautifully and with punch IMO, especially in the bass department. Should never have sold them, but with the tiny space I had available, I couldn't keep them when I got my 9's shipped here.
Maybe let's try comparing ads from something like the same decade. This with Miles Davis is from 1971. Not that print ads are especially relevant to anything here, but I find nothing appealing to "eggheads" in referencing Davis, accuracy, lack of coloration and professional musicians. I knew rock listeners who hugely appreciated that sort of thing decades ago. I still do. Here's a (latter) '60s ad. I suppose the reference to live music could be the egghead appeal, but if that's the case, boneheads (good for head banging) need not apply.
That Cerwin Vega ad couldn't help but remind me of this 1976 billboard and make me wonder: if they have pull out the stops with the S&M images to gain attention, just how good can the product be anyway?
I had a pait of AR-92's way back when that sounded decent if you had 200 rms to drive them, 100 rms, not so much. Both tweeters eventually went bad after 5 or 6 years and the woofer surround foam lasted around 7 or 8 years. Make of that what you wish.
I still have my Avid 330s which use the same woofer as the 3s but with updated dome mid and tweeter but in my case I updated the worn out woofers with a Dayton Audio 12" woofer whose specs best matched the original woofers - not a perfect match but close. I also upgraded the X-overs and eliminated a lot of extra circuitry that was designed to protect the tweeter - I put in a light bulb I bought at Parts Express to protect the tweeter! I also added L-pads to adjust the sound to my liking. I plan to rebuild the cab with MDF and adding bracing which this speaker has none of, just like the ARs. Here's a pic of them I found on the net.
Put a little piece of sticky felt on the magnet under that dome and smooth out the highs. Here is a horn mid I recently did some work to.
Been having difficulties mastering the use of a picture hosting site. The above reflects that. Pics, out of order, no explanation. So I’ll start over. Below is the untouched original phenolic dome. Yellow blobs are foam. A clear membrane was painted on over the foam, and over the entire dome perimeter. This is a “build in place” surround for the dome. It seals out dust, centers the dome, and provides an elastomer suspension for dome movement. But it’s also very restrictive, tying the dome’s movement down. It limits power response. Below is the VC gap after using a razor knife to cut the membrane and the foam. There are 4 notches in the steel faceplate for the foam suspension/damper. The steel faceplate is part of the magnetic circuit. So using steel tools on the faceplate is a challenge. Below, cleaning out the foam residue from the 4 notches: Below, the freed dome: Below, part of the challenge. Under the dome is a stack of fiberglass batting. It puts a substantial preload on the dome, making it want to pop up. So when the dome is remounted, it has to be compressed in place.
Cerwin Vega was a very good product at doing what it was designed to do. Now, whether that matches with what somebody wants to hear is a different matter. Their speakers made my ears bleed. The JBL speakers I heard while I worked there also made my ears bleed, just to a lesser extent. I don't think AR speakers ever caused ear bleed, any more than a Quad electrostatic would.
After cleaning out the gap and the voice coil residue, I test fitted the dome back in the gap. I had to come up with a way to clamp the dome in place. I landed on using a thick steel washer. The powerful magnet draws the steel washer down, in addition to its mass. I used a 0.015” (1/64”) feeler gauge to establish a vertical gap between the outer edge of the dome and the steel face plate. Below, a test fitting. I was able to get an even vertical clearance of 1/64” all around the dome edge: The tricky part: What to use for sealant, and even trickier, what to replace the yellow foam with? I’ve been making my own compound for repairing cantilever suspensions for 5 years now. So I borrowed from that end of the hobby. I use a clear butyl rubber, thinned down, for the membrane. I use clear butyl mixed with a red elastomer, then silicone grease microencapsulated in the compound. It forms an elastic, spongy, acoustically “dead” compound. A golf ball-sized ball of it, when dropped on concrete from 5 feet, will not bounce. It hits and stays there. I used the red compound for the 4 suspension spots, where AR used foam. Also, I did not get the compound on the voice coil windings. It bridges the dome top and steel faceplate at the 4 notches. After curing for an hour, I applied thinned clear butyl rubber using a paint brush: Below, after applying clear butyl. It doesn’t look as messy as this; the flash right after application makes it look messy. Below, I fixed the lead wires in place using acid-free RTV silicone. Originally, AR used electrical tape.
I let it cure over night. Then I used a 1.2 volt battery on the leads to force the dome up, then down, to establish dome movement, and to flex the membrane. Finally, I applied a music signal. This was my first listen after the tweeter rebuild, on only 1 speaker. (I did each speaker separately, so I could compare. This is with pots cleaned, and capacitors replaced.) This shocked me! This speaker had sounded so muffled and lacking treble!
That music track above is from a 1964 Billy Vaughn record. Using the Micro Acoustics MA309 cartridge that I had repaired last year. So I decided to test a modern record. This is the 2022 Octave Records Audiophile Masters Volume I, a compilation album of their studio recordings. On 180 gram virgin vinyl, with only 500 pressings. Same MA309 cartridge:
Here, before rebuilding the tweeter. Same track as above, same cartridge. This is just a later portion of the track. Cymbals are gone, no shimmer. (Barely audible cymbals.) Tweeter pot at 100% setting. (Says M95. That was my titling mistake.) This is the factory AR sound, as they were in 1965:
And, again, both speakers, after tweeter rebuild, playing a 1963 vinyl record of Take Five, by the Dave Brubeck Quartet. In the middle (2:40) you can hear the drummer getting busy with what he does….): No ear bleeds. Just a very nicely balanced sound. Great detail from these old girls! Very musical.
