AR3a restoration.

[speakerdoctor]

I converted a pair of AR1W's into a mirrored pair of Super-moded 3a's. Acoustic measurements didn't show a siginficant difference from non-mirrored pairs.
Below are two pics of in-process cabinets.

[Leakstereo20]

Originally Posted by system7

To a modern eye they look unsophisticated, especially the paper tweeters. But recall the AR-3A was one of the most respected speakers of its time using the now unfashionable acoustic suspension bass.

Without having done any modelling of some of those simple crossovers, it certainly looks like they were quite a lot more time-aligned than other designs. They also seem to have less places for energy to be stored, resulting in a very immediate and lively presentation.

AR3-A used paper dome tweeters.

Well, I don't know what you mean with "the now unfashionable acoustic suspension bass"? ......its hard to find a more controlled bass reproduction than acoustic suspension.
Several different speakers as Kef , JBL , B&W , B&O , Scanspeak among others has been used here, and none......I mean none of them did ever leave me the feeling of being there with the musicians! ....but the AR3a did just that:

Look at the AR3a of mine:
https://picasaweb.google.com/vbkolse...55917072786754

https://picasaweb.google.com/vbkolse...earchAR3aAR11#

And the rest of the AR3a history with mr. Edgar Willshur....then you might get a picture and understand how the tweeter paper cones move the air-molecules and this way sounds more natural. ?:
TUBEAMP look for AR3a

AR some of the best speakers from US.

regards

[phivates]

Your 3a woofers are the early version if the surround is cloth. Sometimes the fiber rings the surround and the spider attach to separate from the alloy basket. Tapping with eraser end of a pencil is one way to locate looseness. Then there's the problem of which adhesive. My luck with CA glues is not great.
Recommendations?

[Leakstereo20]

Originally Posted by phivates

Your 3a woofers are the early version if the surround is cloth. Sometimes the fiber rings the surround and the spider attach to separate from the alloy basket. Tapping with eraser end of a pencil is one way to locate looseness. Then there's the problem of which adhesive. My luck with CA glues is not great.
Recommendations?

My AR3a woofers has foam surroundings, so they are some later types. I do have a link for "soft" epoxy wood and metal glue:
Kb Epoxy harpiks og klbemidler 2031 Sort epoxypastaklbemiddel Araldite 1735208 online fra RS. unfortunately black!!

Very strong and I have not experienced the woodfiber rings getting loose by use of this glue type.

I have a pair of 20003 woofers from AR91 with the "small" fiber woodring. Do you know whether this later 11" AR woofer has different parameters as Fo and VAS ? I tried one and this woofer did not sound as "deep" as my old pair of AR3a woofers....one reason could be that the newer AR91 woofer was nearly unused and the spider was very stiff and not flexible??

rgds. Kim

[Leakstereo20]

Originally Posted by speakerdoctor

I converted a pair of AR1W's into a mirrored pair of Super-moded 3a's. Acoustic measurements didn't show a siginficant difference from non-mirrored pairs.
Below are two pics of in-process cabinets.

Before I saw the AR3a of yours, I thought about making a brand new pair of cabinets for a second AR3a speaker pair of mine . First because MDF hardwood is more heavy and I like to do the woodwork, secondly because I have owned most of the home speakers available, and none of them has pleased me more than Edgar's AR3a.. I like to have them in perfect shape

Attached pair of AR3a in rare birchwood, which I would like to finer with rosewood. I apologize for the rather blurred picture
I think rosewood has a beautiful deep dark colour.

Attached the rather thin fiber woodring of the AR91 200003 woofer before repair of the foam surrounding . Can anyone tell me whether there are diffenrent AR 11" 200003 woofers as far as Fo is concerned?
Last attached picture is a AR11 11" 200003 woofer where the former owner had removed the fiber woodring. I made two new fiber woodrings and glued them on once more.

regards

[Leakstereo20]

Originally Posted by speakerdoctor

I converted a pair of AR1W's into a mirrored pair of Super-moded 3a's. Acoustic measurements didn't show a siginficant difference from non-mirrored pairs.
Below are two pics of in-process cabinets.

Your mirrored AR3a pair looks like that they are made of plywood?...and the stiffening wood pieces looks like solid walnut ...or something like that? The AR3's from Europe are made of veneered chipboard.

Look at the AR3a from Italy. The Italian joiner made a beautiful job....like it or not..the woodwork is ok:

audiocostruzioni.com

Rgds.Kim

[speakerdoctor]

Originally Posted by Leakstereo20

Your mirrored AR3a pair looks like that they are made of plywood?...and the stiffening wood pieces looks like solid walnut ...or something like that? The AR3's from Europe are made of veneered chipboard.

Look at the AR3a from Italy. The Italian joiner made a beautiful job....like it or not..the woodwork is ok:

audiocostruzioni.com

Rgds.Kim

The AR1W's were made with marine plywood. Very water repellent stuff. Some of the cabinets are made with 2 sided walnut veneer. It didn't take long before that changed to single sided.

[Leakstereo20]

Originally Posted by speakerdoctor

The AR1W's were made with marine plywood. Very water repellent stuff. Some of the cabinets are made with 2 sided walnut veneer. It didn't take long before that changed to single sided.

When you say 2 sided...you mean walnut veneer on the inside of the cabinet ? Expensive! Cabinetmakers normally uses a cheap wood type for the inside of the cabinet . This is necessary when the cabinet factory under pressure warms the veneer on both sides of the woodplate, done to avoid any bending of the wooden panel.

Have you ever seen a pair of AR1W's or AR3a in rosewood?
I have just bought rosewood veneer for 175 US$.
I hobe that I can convert my AR3a pair in light birchwood into a beautiful dark pair in rosewood

Rgds. Kim

[phivates]

60+ years ago the bean counters were not so much in charge.

[Gudmund]

Originally Posted by phivates

60+ years ago the bean counters were not so much in charge.

What?