AR3a Pics : half-way mark in restoration

[Guest Eunomians]

Next time I won't be so lazy and I'll get my digital camera out of my car. Instead, you get crappy cellphone pics for the time being.

I have refinished the cabinets and overall, they look minty with some nice patina (or wabi-sabi, if you will). The walnut stands match perfectly in grain direction, color and overall finish. Seems to be a lucky match.

I am in the process of changing the grill cloths and I do have a pair of mint logo badges.

*Stay tuned as I will post pics of this project once 100% completed.

PS. It's hot as hell today!

[Guest russwollman]

Now I understand why you want to date those speakers. They're quite comely.

Who's that cute little fish on the top? She's mighty appealing to an aquatic-minded oddball like me. Is she available?

I like the thicker front section of the 3a's cabinet. It gives them heft and authority, which of course they have in every other way—sort of like an early 1960's Lincoln Continental. And 3a's are heavy, too—just as those Lincolns are.

I had a pair for a while, with some different stands. Even on their perches, they looked immovable, imperturbable, maybe even eternal...

[RoyC]

Do the woofers have foam surrounds? What appears to be damping material (the darker ring around the dust cap) seems somewhat different than other 3a woofers...especially in cabinets with serial numbers similar to yours.

A close up of the woofer would be most appreciated if you are able to provide one for us.

Thanks!

Roy

[Guest Eunomians]

>Do the woofers have foam surrounds? What appears to be

>damping material (the darker ring around the dust cap) seems

>somewhat different than other 3a woofers...especially in

>cabinets with serial numbers similar to yours.

>

>A close up of the woofer would be most appreciated if you are

>able to provide one for us.

>

>Thanks!

>Roy

Mmmm, interesting... I will take some detailed pics of the woofers shortly.

[Guest Eunomians]

Here are some closeups of my woofer...

[dynaco_dan]

Hi there;

I see that you have the pre-foam woofers, lucky you.

Early AR-3A's woofers used the earlier cloth surrounds and damping rings, the same as the AR-3's.

My guess is, just to use up old stock woofers.

I prefer this particular woofer, because of it's no-rot surround.

There may be a sonic difference between the woofers, I do not know.

Any difference will be smaller, than say, with an AR-1W speaker system with it's greater usable frequency response.

Others may prefer other iterations of the woofer.

Very nice speaker system.

[RoyC]

Great photos...Thanks!

You have the earlier version woofer (used in the '60's) with cloth surround and damping ring. It would not have been the type that was originally installed in cabinets with your serial numbers. That is not a bad thing, as they are great woofers. It just means there was work performed on the speakers at some point.

The cabinets having backwired mids and tweeters is consistent with the mid 70's version of the 3a.

Roy

[Guest Eunomians]

Ahhh, this is great news regarding the foam issue. I have owned quite a few speakers that have all rotted in due time; this is the reason why I actually picked up these AR3a's, to replace my last dead speakers.

Thank you gentlemen for your insight (I am quite new to the speaker/vintage audio realm).

I was initially wondering about the serials because I had noticed that the surrounds were indeed not foam but that the mids/tweets were not front-wired. I was curious about this discrepancy & certainly wondered if there was any work done on them at some point. The woofer screws don't seem to show any screwdriver wear though. Evidently, whoever did the work did so with the utmost care. Anyhow, I am quite intrigued to say the very least.

I will post pics of my AR3a's once I replace the grill cloths & logo badges.

[RoyC]

You may get more clues regarding any past work done on your speakers when you open the cabinets to restore the level controls. Are they working OK? If so, the work probably included that common task as well.

Roy

[johnieo]

I agree, Roy. AR-3a with serial numbers up to about 38,500 used Alnico-magnet cloth surround woofers; after that date, ceramic-magnet foam surround woofers. That transition happened mid-1970. The back-wired mid and tweets are consistent with the 102,xxx serial numbers and late 75 manufacturing date. It is likely that someone removed a pair of badly deteriorated foam surround woofers and replaced them with early models. Regardless of how/why they arrived in these cabinets, you are the winner; no future refoaming hastles! You might examine the perimeter seal, where the surround ring attaches to the cast aluminum basket. Some old woofers have been known to delaminate in spots. Such regions can be repaired with latex surround glue if necessary. Likely the non-polar electrolytic capacitors are past end of life as well.

[Guest Eunomians]

I will check out the perimeter surround again. My previous inspections found no apparent wear, but you never know.

The level controls are a bit scratchy whilst turning them; but, they do work (and don't cut out). I did spray a little Deoxit/Progold into them - not sure if it made an real difference though, aside from essentially lubricating them. I do believe that a little service is due on them though. I guess the next step is to find a competent & recommended repair person here in Los Angeles. This is where I am at a complete loss though. I do know of a speaker repair guy in the Silverlake area, but I do not know the quality of his work - especially in regards to old AR stuff. I would certainly entertain any suggestions for a repair specialist as well as the kind of work that I should get done on them to optimize them & keep 'em purrrring.

Cheers

[JKent]

DIY!! You've already made them look pretty (nice job) and you don't have to refoam them. Fixing the pots is a breeze, and you'll get lots of help here. See the thread on my 2ax restoration:

http://www.classicspeakerpages.net/dc/dcbo..._id=10022&page=

All you have to do is remove the woofers to get at the level controls (pots). Take pictures, make drawings of how the wires are attached. I don't know if you will have to de-solder and re-solder the wires. The pots come apart easily, and there are threads here on cleaning them. Basically, you want to get all the green crud (oxydation) off. I used a little wire wheel in a dremel tool, but you can use sandpaper or emory cloth and lots of patience. THEN clean/treat the contact points with your DeOxIt, put it back together, and you're in business. Just be sure to get the metal parts inside REALLY CLEAN! Attached are before-n-after pics a member sent me when I started my project. Good luck!

P.S. Looking at the pic, it's not clear, but you have to clean both the metal parts in the ceramic half, as shown in the center item, AND the metal "bumps" (contact points) on the piece in the metal housing (on the end of the shaft) shown on the right

[tysontom]

Actually, those Alnico woofers are from an early 1960s AR-3: they have *both* foam damping rings -- the inner ring and the outer ring close to the surround. The AR-3a (from 1967 through the late-1969, early 1970 changeover to the ceramic woofer) had the Alnico woofer with only the inner damping ring. It was found that using butyl-latex compound on the cloth surrounds actually worked about as well as the additional foam damping ring.

The good news here is that this woofer was one of AR's best. It was a highly compliant, low-resonance version with low distortion. As the years went on mechanical-suspension compliance (stiffness) began to increase in the interest of power-handling safety and reliability; but around 1961 or 1962 (when these woofers were probably manufactured) the free-air cone was loose and the suspension was only sufficient to hold the assembly centered together in the gap. The rest was left to... air! Pure acoustic-suspension!

One question might be if the cabinet stuffing is the right weight and density (fiberglass?), and if the #7 or #9 coil is in the circuit.

--Tom Tyson

[johnieo]

Tom: Thanks for describing the difference between the AR-3 and -3a woofer. Haven't seen enough of each to know there was a difference. The value of fs in my pair of 1960 AR-3 woofers was measured to be 13 Hz. Like you say, very floppy! The later AR-3 ceramic magnet woofers had an fs of 18-21 Hz.

Do you know how much fiberglass was supposed to be used with that woofer? The early 3a had 28-to-30 oz. Was the AR-3 stuffing of similar weight or greater?

These 3a cabinets mfg in 1975 would only have 20 oz. and likely a #9 coil. One might guess the inductor size is not an issue, but 20 oz. of fiberglass would impact the Q.

[Guest danamc]

Interesting discussion of serial numbers John. This is a photo of the serial # and speaker of a set I've owned for years. Ain't this fun?

Dana

1385.txt

1386.txt

1387.txt

[tysontom]

>Tom: Thanks for describing the difference between the AR-3

>and -3a woofer. Haven't seen enough of each to know there was

>a difference. The value of fs in my pair of 1960 AR-3 woofers

>was measured to be 13 Hz. Like you say, very floppy! The

>later AR-3 ceramic magnet woofers had an fs of 18-21 Hz.

>

>Do you know how much fiberglass was supposed to be used with

>that woofer? The early 3a had 28-to-30 oz. Was the AR-3

>stuffing of similar weight or greater?

>

>These 3a cabinets mfg in 1975 would only have 20 oz. and

>likely a #9 coil. One might guess the inductor size is not an

>issue, but 20 oz. of fiberglass would impact the Q.

John,

The differences were minor, but later changes to the AR-3 Alnico woofer (PN3700) applied to the early AR-3a woofers as well. In other words, the late-model AR-3 and the early AR-3a used identical Alnico woofers. The believe the outer damping ring went away somewhere in the early 1960s and the fiberglass weight in the AR-3, although it changed somewhat over the years, was the same as the 1967-1970 AR-3a with the Alnico woofer. Some early AR speakers had a rock-wool-like fiberglass substance, but most used the standard Owens-Corning or similar fiberglass. Incidentally, the earliest AR-3 woofers had plain-side cones with *no* damping rings whatsoever -- a vestige of the AR-1.

Early on, AR determined the optimum amount of fiberglass for each iteration of AR speaker (regarding a woofer upgrade, etc.) by measuring the woofer's frequency response and damping with adjustments (either more or less fiberglass) made to optimize the Q (in the AR-3 and AR-3a) at somewhere between 0.7 and 1.0.

--Tom Tyson

[tysontom]

>Interesting discussion of serial numbers John. This is a

>photo of the serial # and speaker of a set I've owned for

>years. Ain't this fun?

>

>Dana

These early AR-3as (1968 probably) demonstrate the later-version of the Alnico 3700 woofer without the outer damping ring. This woofer was slightly more rugged than the earliest 3700.

--Tom Tyson

[Guest Bret]

>Who's that cute little fish on the top? She's mighty appealing to an aquatic-minded oddball like me. Is she available?<

"It's people like you what cause unrest."

[Guest Eunomians]

This all very fascinating information.

I wonder if I have the appropriate amount of fiberglass stuffed into my speakers. Surely they sound pristine to me, but then again I have had no other reference points with AR3a' s (since mine are the first AR3a's I have ever heard).

I will attempt to clean the pots - not doing so will drive me crazy since I've almost fully restored them... Thank you for your pics & support/information. Your speakers look great.

...The ultimate step is regarding optimization. For this step, I need to find a professional speaker repair specialist in Los Angeles. I would like someone to tweek them to optimum specs. 'Tis a great thing to learn that my woofers are different so that when I the speakers serviced, they can be serviced correctly.

Cheers

[Carlspeak]

>This all very fascinating information.

>

>I wonder if I have the appropriate amount of fiberglass

>stuffed into my speakers. Surely they sound pristine to me,

>but then again I have had no other reference points with AR3a'

>s (since mine are the first AR3a's I have ever heard).

>

>I will attempt to clean the pots - not doing so will drive me

>crazy since I've almost fully restored them... Thank you for

>your pics & support/information. Your speakers look

>great.

>

>...The ultimate step is regarding optimization. For this

>step, I need to find a professional speaker repair specialist

>in Los Angeles.

I suggest you contact Orange County Speaker Repair.

Visit their website: http://www.speakerrepair.com

They are quite knowledgeable and have a store front you can visit and talk to Bryan Sunda about what you want done. Please tell him Carl's Custom referred you.

thanks,

Remember, it's all about the music

Carl

Carl's Custom Loudspeakers

[Guest russwollman]

Whew! Bret, I'm relieved you finally figured that much out. Gotta run now, there's other feathers that need ruffling and some pots in need of a stiffening stir...

[Guest Eunomians]

>>This all very fascinating information.

>>

>>I wonder if I have the appropriate amount of fiberglass

>>stuffed into my speakers. Surely they sound pristine to

>me,

>>but then again I have had no other reference points with

>AR3a'

>>s (since mine are the first AR3a's I have ever heard).

>>

>>I will attempt to clean the pots - not doing so will drive

>me

>>crazy since I've almost fully restored them... Thank you

>for

>>your pics & support/information. Your speakers look

>>great.

>>

>>...The ultimate step is regarding optimization. For this

>>step, I need to find a professional speaker repair

>specialist

>>in Los Angeles.

>

>I suggest you contact Orange County Speaker Repair.

>Visit their website: http://www.speakerrepair.com

>They are quite knowledgeable and have a store front you can

>visit and talk to Bryan Sunda about what you want done. Please

>tell him Carl's Custom referred you.

>thanks,

>

>Remember, it's all about the music

>

>Carl

>Carl's Custom Loudspeakers

Wow Carl, thank you for the info, I will indeed tell him that Carl's Custom referred me.

Now, I am wondering what I should have checked out. I will discuss the issue of the quantity of fiberglass that I need for my early woofers. I wonder what else I should inquire about? The dirty pots for sure, but I am not sure what else. Caps? Fusing? New wiring? I can tell you right now that they sound incredible, but what do I know, I am still a newbie in this game.

I have finished changing the grill cloths and slapping on the badges - the speakers look utterly fabulous. I will post hi-res pics tomorrow. Wow.

Cheers

[tysontom]

>

>Now, I am wondering what I should have checked out. I will

>discuss the issue of the quantity of fiberglass that I need

>for my early woofers. I wonder what else I should inquire

>about? The dirty pots for sure, but I am not sure what else.

>Caps? Fusing? New wiring? I can tell you right now that

>they sound incredible, but what do I know, I am still a newbie

>in this game.

>

>I have finished changing the grill cloths and slapping on the

>badges - the speakers look utterly fabulous. I will post

>hi-res pics tomorrow. Wow.

You probably should *not* discuss the issue of fiberglass in your AR-3as with this "professional speaker repair person" in LA. How would he know the optimum amount unless he is a hard-core, bonafide AR aficionado (all of whom reside on this forum). He might even tell you to replace all the fiberglass with Polyester Fiberfill to give your speakers "tighter bass." Incidentally, there is no such thing as "tight bass." Nevertheless, the correct amount of fiberglass -- plus or minus a small amount -- is most likely already in each of your speakers. New caps? Perhaps, but only if you think there is a problem. Do you hear distortion, stridency or other strange sounds? New wiring? It will have zero impact on the overall scheme of things, but it will pad the pocket of the psrp in LA. Dirty pots? If you are getting output from both midrange and tweeter drivers in both speakers, and the range of adjustment is enough to get both speakers approximately the same, you may not need to do anything with the controls at this time. Besides, if these speakers sound "incredible," which is the proper description for a pair of AR-3as, then perhaps you shouldn't change anything and just sit back and enjoy the music.

--Tom Tyson

[Guest Eunomians]

Tom, I appreciate your comments, thank you.

For the time being, I will sit back and enjoy them now that I have finished restoring them.

Best regards

And now, time for some quick snaps - more to follow once I get the nicer camera out of my car.

New grill cloths installed, grill frame reinforced, new velcro stapled to the inside of the speaker as well as to the inside of the grill frame. Oh, and logo badges!

Dang, they now look as sweet as they sound.

Better pics to come real soon. Enjoy.