AR3's

[Paul W]

Hi all,

I've had these AR3's stored for a number of years now and thought it was time to look at the potentiometers,   I've not had much luck cleaning them, The potentiometers are still intermittent? If anything Possibly worse 😕 

All the drive units work fine if I get the potentiometer in a sweet spot and wow sound superb, but then goes intermittent again from vibration I think? 

Question 1 . 

There looks to be 2 sellers on ebay that sell a correct type of replacement potentiometer, has anyone used these ?

 

Question 2.

I had been advised that the capacitors in speakers are possibly fine and don't have the same issues as power supplies capacitors ? Any thoughts on this ? 

 

Question 3.

Do these look like original speakers units ? from just looking at the photos ? All the screws around the units look un-chewed / untouched,  I don't fancy taking the mids and tweeters out to get serial numbers as these look so delicate and I wouldn't want to break anything. Unless I really have to ??

 

Question 4.

I did see a post on here talking about different woods being used in production,  any ideas what these are made from ?

 

Question 5.

I don't have the time to fully restore these and certainly no space to keep them any longer.

Any ideas who would be interested in buying these AR3's ? And what these maybe worth? £ $ £  To the right person? 

I'm located in the United Kingdom 🇬🇧

And as you'll know,  my god they weigh some and I wouldn't want them to get damaged so I'm thinking international shipping is a no no.

Please see the photos, I can take more if required? 

Many thanks,

Kind regards

Paul 

 

 

 

[Giorgio AR]

Wonderful: these are AR3s, quite early and then updated to AR3a (you can guess this from the mid's and tw's owners of the AR3a), usually on the back of the cabinet the update was recorded, in this case not.
From what you see and the mid's, tw's and capacitors in the cabinet, the update probably happened in '74 or shortly before.
The woofer's and mid's capacitors look sprague and should be in order (a check of the values is still recommended).
In my opinion, from what you see in the photos, they are very well maintained speakers with minimal aesthetic defects, the only non-uniform detail, the fabric of the grille cloths to be replaced with another similar to the original (in this case the choice between the look of AR3 and that AR3a is yours alone!).

[JKent]

Welcome Paul

Beautiful speakers! Like you, I have 3s that were converted to 3a (but I did it myself). Giorgio's advice about the caps is good but that wax capacitor is most certainly toast. The Sprague can caps "may" still be good but electrolytic capacitors in speakers rarely last more than 30 or 40 years without going out of spec (sometimes spectacularly so). Your caps are going on half a century, at least. 

Regarding your other questions, I "was" one of the 2 sellers on ebay with the replacement pots. Unfortunately I've sold out (I was selling them here on CSP for $30/pair compared to the other guy's $30 each). Those pots are very good, heavy-duty. Kind of stiff to rotate but I'd say very good build quality. OTOH, L-pads work fine for much less money. They may not be original to the 3/3a but AR did switch to L-pads for later models (maybe the 3a Limited?). Nothing wrong with them. Be sure to download the AR-3a restoration booklet. It will answer a lot of questions http://www.classicspeakerpages.net/library/acoustic_research/original_models_1954-1974/original_models_schematicss/restoring_the_ar-3a/

DO NOT remove the mids and tweets. You're right: too risky and no need.

I'm guessing they're walnut but there's a chart somewhere in these pages that shows the wood options.

If you don't plan to keep them my advice is don't touch them. Leave them "unmolested". We have a few members in the UK and maybe one of them would be interested.

Kent

[Giorgio AR]

Regarding the wood of the veneer, as there is no other reference in the back of the cabinet, this should be oiled walnut; I would add that the paper and wax capacitor of the tweeter (the soap-shaped box) is usually out of tolerance even over 100%, it is the only one that certainly needs to be replaced.
The frames of the grilles are original in plastic material of the AR3 and from what you see intact, so they probably deserve a fabric similar to the original that you can find, with difficulty in the USA (there is a specific thread on the site, but not I can find it).
Finally the Pots were available at a very fair price thanks to the great JKent, under a reference.

 

[Aadams]

19 minutes ago, JKent said:

If you don't plan to keep them my advice is don't touch them. Leave them "unmolested". We have a few members in the UK and maybe one of them would be interested.

 

Agree.

Also I had a similar cap arrangement like that in some 3as.  The reddish cap was a Sprague but the silver can cap was an ICC Royalitic.   It probably makes more sense to replace all of them.  Just my 2c.

[Giorgio AR]

10 minutes ago, JKent said:

Kent

We were simultaneous ... but I had to recommend your Pots.
The only case of spare parts sold by enthusiast to other enthusiasts at a true friend's price !!!

The ones I bought from you are still in their boxes, I have not been able to progress in the restoration of my AR3a early due to my job as a nurse in the Prevention Department causing the Covid pandemic takes me much beyond normal working hours !!

All postponed until the contagion situation drops to lower values, currently Trieste and Friuli Venezia Giulia have the negative record in Italy! We also got on the front page of the "New York Times" as a negative example and high numbers of infected! I do not comment on the causes, independent of the commitment of the state and of the health workers involved in limiting an exponential increase in cases.

[Paul W]

15 hours ago, Giorgio AR said:

Wonderful: these are AR3s, quite early and then updated to AR3a (you can guess this from the mid's and tw's owners of the AR3a), usually on the back of the cabinet the update was recorded, in this case not.
From what you see and the mid's, tw's and capacitors in the cabinet, the update probably happened in '74 or shortly before.
The woofer's and mid's capacitors look sprague and should be in order (a check of the values is still recommended).
In my opinion, from what you see in the photos, they are very well maintained speakers with minimal aesthetic defects, the only non-uniform detail, the fabric of the grille cloths to be replaced with another similar to the original (in this case the choice between the look of AR3 and that AR3a is yours alone!).

Cheers great info thank you 

[Paul W]

5 hours ago, JKent said:

Welcome Paul

Beautiful speakers! Like you, I have 3s that were converted to 3a (but I did it myself). Giorgio's advice about the caps is good but that wax capacitor is most certainly toast. The Sprague can caps "may" still be good but electrolytic capacitors in speakers rarely last more than 30 or 40 years without going out of spec (sometimes spectacularly so). Your caps are going on half a century, at least. 

Regarding your other questions, I "was" one of the 2 sellers on ebay with the replacement pots. Unfortunately I've sold out (I was selling them here on CSP for $30/pair compared to the other guy's $30 each). Those pots are very good, heavy-duty. Kind of stiff to rotate but I'd say very good build quality. OTOH, L-pads work fine for much less money. They may not be original to the 3/3a but AR did switch to L-pads for later models (maybe the 3a Limited?). Nothing wrong with them. Be sure to download the AR-3a restoration booklet. It will answer a lot of questions http://www.classicspeakerpages.net/library/acoustic_research/original_models_1954-1974/original_models_schematicss/restoring_the_ar-3a/

DO NOT remove the mids and tweets. You're right: too risky and no need.

I'm guessing they're walnut but there's a chart somewhere in these pages that shows the wood options.

If you don't plan to keep them my advice is don't touch them. Leave them "unmolested". We have a few members in the UK and maybe one of them would be interested.

Kent

Hi, thanks for you comments. that looks very interesting the AR-3 restoration booklet. 

[Paul W]

5 hours ago, Aadams said:

Agree.

Also I had a similar cap arrangement like that in some 3as.  The reddish cap was a Sprague but the silver can cap was an ICC Royalitic.   It probably makes more sense to replace all of them.  Just my 2c.

Hello cheers