AR 6 restoration - advice required before getting started

[AR6_Project]

I’ve been looking for a set of vintage speakers for a) a fun project and b) to kick off a new intro setup and was drawn to the aesthetic of the 70s Acoustic Research. I was able to pick up these AR-6s which seem to be an early set and in decent condition on first look.

Whilst looking for resources online I’ve noticed that many on this forum have been very helpful in providing information for inexperienced restorers like myself (paging ra.ra).

They don’t appear to have been opened up at the back at all. I’ll post some pictures as they are and would appreciate any thoughts from people who might have done this before. With a bit of TLC these should scrub up well!

Thanks,
Mike

 

[r_brumett61]

I’ve been looking for a set of vintage speakers for a) a fun project and b) to kick off a new intro setup and was drawn to the aesthetic of the 70s Acoustic Research. I was able to pick up these AR-6s which seem to be an early set and in decent condition on first look.

Whilst looking for resources online I’ve noticed that many on this forum have been very helpful in providing information for inexperienced restorers like myself (paging ra.ra).

They don’t appear to have been opened up at the back at all. I’ll post some pictures as they are and would appreciate any thoughts from people who might have done this before. With a bit of TLC these should scrub up well!

Thanks,
Mike

 

[StimpyWan]

Welcome!

There's good info on the AR-6, at Classic Speaker Pages.

AR-6 search

This thread has crossover schematics too.

AR-6 schematics

Good luck, and I hope you enjoy your new AR's.

 

[swechsler]

They look like the granddaddy of the AR-18.

 

[ra.ra]

With a bit of TLC these should scrub up well!

Hi Mike, and welcome to AK. That's a really fine-looking pair of excellent vintage speakers you have there. Just from your pics and brief description, here's a few thoughts and observations to chew on:

• grilles look to be in very good condition - - only missing one badge
• cabinets look very good, too, but we cannot see the major faces of veneer - - yours are the Euro styling with thin front edge profile
• Euro version also confirmed by England address on label and the E prefix in the serial number
• tweeters look great - no dented domes!
• woofers appear to be the earliest (best?) version with ribbed cone - - this can be confirmed if they have large alnico slug magnet
• am curious about those triangle shapes on the woofer dust caps

The AR-6 was produced in several iterations, and my guess is that you have the early (A) version - - Stimpy has already provided some links to lead you to crossover variations. On the backside, do yours have the three terminals and the rotary pot control?

They don’t appear to have been opened up at the back at all.

There is no access thru the back on these speakers - - - all work and inspection must be done thru the hole resulting from removal of 8-inch woofer. Yours may have the multi-color stuffing, too, but please post more info and pics as you dig in.

 

[edlipman]

Hey:
The woofers need refoaming , they are coming apart , see the woofer cones sagging in the speaker.
Then the capacitors in the crossovers need to be replaced.
Also the level pots in the back need to be cleaned and checked for operation , see if they affect the sound when the speakers are hooked up to an amp. At low level you should hear sound when you turn the pots , even if there is noise and scratchy sound.
They will sound great when refoamed and the crossovers repaired.

 

[ra.ra]

I was able to pick up these AR-6s

Yoo-hoo, we're still out here - - - what happened to the OP? - - one post and disappear?

 

[AR6_Project]

Hi guys, apologies for the delay in response! The beginning of the year was crazy with work, but now that much of the world is self-isolating I’ve decided to dig these back out and use the opportunity.

Thanks for all of your help and messages - I admit that I only managed to read some of these a couple of days ago so I will try to answer your questions and figure out how to get these back into working order.

Ra.ra - hopefully the first image answers your question about the pots. Attaching more pics as requested!



Second image shows a tweeter dome on one of the speakers which appears to be dented!


The woofer cone also looks quite warped. Would appreciate thoughts on these.


Stimpy and edlip thanks for your helpful links and comments. Attaching a pic of the guts:


I’ll start looking at the schematics and figuring out which parts I need to order. Further advice welcome.

 

[Nat]

The dent in the tweeter probably has little effect, and while you could try pulling the dent out with a hooked pin and then dabbing a little white glue on it to seal, it should be way down the priority list.
I've been surprised at how warps in woofer cones are diminished or removed completely by refoaming. You have to make sure that the glue really holds, but the foam resists shearing, so it tends to flatten out the irregular edge.
If your potentiometers work, keep them, though there are various vinegar and salt soak type cures that may help restore them to new(ish) behavior rather than the crochety wilfulness they typically exhibit now. The old capacitor is the only component that might be worth replacing, but it is a paper and foil cap, and I don't know wether they go bad. I suspect the ESR is higher than a modern poly cap, but that may or may not be a good thing. I'd see what they are saying over at Classic Speakers, or post the question here.

 

[AR6_Project]

Thanks for the tips, Nat. For the refoaming, would you recommend a specific kit, or are they fairly standard? Something like this, for example?
https://www.ebay.co.uk/itm/164100615591

I think there are some guides on restoring the pots on here and Classic Speakers so I’ll check them out and ask around about the capacitors.