AR 4xa or AR 6?

[jank]

I have a pair f 4xa speakers that I picked up on a flea market. The woofers seems to be non-original but the sound pretty good anyway. This week i found a pair of fully functional AR 6 on the net that will be delivered to me today. So the question is should I use the woofers in the 6s to restore my 4xa to original shape or should i just use the 6s as is and get rid of the 4xa:s? I will of course listen to both. One thing is that I like the shape of the 4xa:s better. Ideas?

Regards,

/jan

[Tunedguy57]

If original and well working I'd keep 6' as first choice. But it should be interesting to know what woofers are mounted on your 4ax. Original ones had cloth surrounds and are not interchangeable with 6' ones, being their Fs about 37Hz, instead 24Hz of those on 6 model. IHMO 4ax was an unlucky version, some way worse than previous 4x. Regards. Tunedguy57

[JKent]

Welcome jank

I hope ra.ra comments because he has a lot of knowledge about both the 4 and 6 series speakers. I suspect Tunedguy57's advice is sound.

Here's a site that briefly compares the two: http://www.vintage-speaker-review.com/2013/11/acoustic-research-ar-6-review-and-price.html

There are several threads discussing the AR-6. They seem to be often-overlooked gems.

-Kent

 

[Tunedguy57]

I remember a post from RoyC where he wondered if AR was ever satisfied of 6 model. I think he was right. Since there are not less than four version of 6.  Woofer and xover change during six-seven years of production. So things are some confused on their performance. In my opinion it should need specify first which version we are speaking about. My first 6 (european made in Holland) had only a 6 uF capacitor  for tweeter and a switchable resistor. No coil, no pot, nothing. Other pair I got later had a coil for woofer and a 10ohm resistor across it.  First series had an alnico magnet woofer. Later it was ceramic.  I loved 6, but it has been  a difficult love. It was anyway my first love. Now I have 4x, 3a, 5, 6, 7 and I do love all of them.

[Giorgio AR]

Tunedguy is correct, just the technical difference between the 8 "AR6 woofer and the AR4xa woofer. Below the photos of the  AR6 woofers (first series) and AR4xa (200001-3).

Then the photo of an AR6 speaker with the replacement woofer next to it, ric. 200001-1, then you see a pair of AR4xa next to an AR4x and its woofer
Finally, overview of four woofers: AR6, 200001-1, pair of AR4x.

 

[Giorgio AR]

Jank,I think thath all the 8 "classic woofers can sound like spare parts in AR4x, AR4xa, AR6, AR7, AR8s, AR18, AR17 etc.

I add photos of various series of my 8 "woofers, in order:

AR7 first series (does not include the number, but has a stamp on the magnet 568 730 ?? and is specific for AR7 and AR MST, this woofer has incorrect assembly foam under cone) the last two photos illustrate the back of the woofer.

AR4xa first series

AR6 first series spare part (200001-1)

AR6 second series 200001-1

AR6 first original series (200001-3)




In conclusion I would keep both pairs of speakers looking for original and compatible components or spare parts: in any case I would look for the 200001-1 woofers or otherwise a great universal substitute for the 200037 woofer!

[ra.ra]

On 4/10/2019 at 9:28 AM, Tunedguy57 said:

I remember a post from RoyC where he wondered if AR was ever satisfied of 6 model.

I think Roy's suspicion here is probably accurate, but it has also been documented that there have been component changes in AR speaker models going all the way back to the AR-1. And let's not even apply this rationale to the "2" series, which had at least seven iterations: AR-2, 2a, 2x (two versions), 2ax (two versions), and 2xa.

As Giorgio's posts clearly illustrate, there were a variety of components used in both the AR-4x and AR-6 models. The 4x was far more consistent than the 6 in this regard, but nonetheless the 4x had more than one version, including different woofers, different badges, and different crossovers. The AR-4xa can also be found with a number of variables: cloth surround or foam surround; alnico slug magnet or square ferrite magnet; pot control or switch; front or rear-wired tweeter; fiberglass or fiberfill stuffing; and wood veneer or vinyl cabinet finish. For this discussion, it would be most helpful if you posted pics of your particular speakers so that the specific components could be properly identified and evaluated. 

The entire "4" series and the AR-6's are all favorites of mine. When I got acquainted with my first pair of 6's, there were several things that really appealed to me. Although the interior cabinet volume is identical to the 4 cabinets, there was a noticeably deeper extension of LF reproduction - - very impressive bass output for an 8-inch woofer. The small 1-1/4" tweeter is also excellent - - very good dispersion and upper high end - - most notable with brushes on cymbals and violins, e.g. 

I agree with the OP (jank) that the AR-4xa (or 4 or 4x....) cabinet has wonderful proportions - - it really is a handsome small speaker. But two things about the AR-6 cabinet are particularly attractive to me. The first is the shallow depth (7-1/2"), which makes this speaker truly suitable for bookshelf applications; and the second is the aspect ratio - - the relationship of width to height. I know this is going deep into nerd territory, but the ratio of height (19.5") to width (12") results in 1.625, which is visually indistinguishable from 1.618, which represents the golden ratio or golden mean or golden section. The result is a very beautiful speaker package.

https://en.wikipedia.org/wiki/Golden_ratio  

[Tunedguy57]

15 hours ago, ra.ra said:

it has also been documented that there have been component changes in AR speaker models going all the way back to the AR-1. And let's not even apply this rationale to the "2" series, which had at least seven iterations: AR-2, 2a, 2x (two versions), 2ax (two versions), and 2xa.

I agree, absolutely,  usually various version of speaker have had a new suffix ( 2a, 2ax, 2x, 4x, 4ax) but 6 in its various issues never had anything to say: "I' m a new version!" . So one can have in his hands a minimalist 6 ( european, only one capacitor for tweeter) or a much more complex 6 with a completely different xover. It could be ok, if they should sound similar, but unfortunately they don't.

[ra.ra]

On 4/10/2019 at 1:36 AM, jank said:

...should I use the woofers in the 6s to restore my 4xa to original shape....

Hi jank, can you post some pics of the speakers being evaluated? 

On 4/10/2019 at 8:30 AM, Tunedguy57 said:

IHMO 4ax was an unlucky version, some way worse than previous 4x.

Can you explain your thoughts here concerning the 4x and the 4xa? The 4xa is a very fine small loudspeaker, but it largely suffered because it was introduced at a time when AR had two other small 8-inch two-ways in their lineup (AR-6, AR-7). IMO, it's lack of distinction and popularity is principally due to poor marketing strategies, and not due to relaxed engineering standards.

When one of the tweeters in my original pair of 4x's inexplicably went silent, due to my stash of parts on-hand, my decision was to re-build this pair as modified 4xa's by fabricating adapter plates to accommodate the smaller tweeter in the original 4x tweeter hole - - - also replaced original 20uF cap with 10uF. No further changes were made, and these speakers are terrific (see pic).  

On 4/12/2019 at 5:36 AM, Tunedguy57 said:

...if they should sound similar, but unfortunately they don't.

I'd be interested to hear your thoughts on this, too. My understanding of this may be incorrect, but I've always thought that each version of AR-6 was intended to create an identical set of sonic characteristics, despite the significant changes in components during its years of production.

My abilities to adequately describe differences in sound are woefully insufficient, but I would tend to agree that all of my AR two-ways are unique and do exhibit subtle differences. On any given day, I might prefer the sound of pair A over pair B or pair C; but then on another day with a different power source or different musical style, I might have a completely different evaluation of the very same speakers under comparison. 

[jank]

Hi and thanks a lot for all comments and pictures. I've now listened to the AR 6 and the sound great to my ears - a huge improvement on my AR 4xa (with the unknown woofers...). I'll try to post a picture of the mystical woofer (It doesn't resemble any of the pictures in this thread). Maybe someone can identify it? If not I might pry the woofers out of the enclosure to take a look. But I think I already decided to keep the AR 6s in any case. And the fact that they come close to follow the golden ratio in their shaps adds to the appeal... /jank

[Giorgio AR]

On 4/15/2019 at 8:57 PM, ra.ra said:

Hi jank, can you post some pics of the speakers being evaluated? 

Can you explain your thoughts here concerning the 4x and the 4xa? The 4xa is a very fine small loudspeaker, but it largely suffered because it was introduced at a time when AR had two other small 8-inch two-ways in their lineup (AR-6, AR-7). IMO, it's lack of distinction and popularity is principally due to poor marketing strategies, and not due to relaxed engineering standards.

When one of the tweeters in my original pair of 4x's inexplicably went silent, due to my stash of parts on-hand, my decision was to re-build this pair as modified 4xa's by fabricating adapter plates to accommodate the smaller tweeter in the original 4x tweeter hole - - - also replaced original 20uF cap with 10uF. No further changes were made, and these speakers are terrific (see pic).  

I'd be interested to hear your thoughts on this, too. My understanding of this may be incorrect, but I've always thought that each version of AR-6 was intended to create an identical set of sonic characteristics, despite the significant changes in components during its years of production.

My abilities to adequately describe differences in sound are woefully insufficient, but I would tend to agree that all of my AR two-ways are unique and do exhibit subtle differences. On any given day, I might prefer the sound of pair A over pair B or pair C; but then on another day with a different power source or different musical style, I might have a completely different evaluation of the very same speakers under comparison. 

Ra.ra, wonderful the work of removing black paint and cleaning the frame around the cloth surround, the woofer so take a better look!

[Giorgio AR]

Jank, keep the AR6 as they are and send photos of the woofer of your AR4xa (woofer photographed in front and back).
If they are not original you will find a pair of 200001-1 or 200037 that will complete your AR4xa with satisfaction (and little expense if you are patient).

Giorgio

[Tunedguy57]

@ra.ra

About 4xa I wrote "someway unlucky".  And IMO it was, I agree with you about strategies of AR for this model.  Personally I prefer the sound of 4x: more smooth and natural human voices. I don't want criticize the Allison's tweeter, actually a beautiful one. About the 6 different performances: even if I do understand that nowadays can be nice comparing and listening different versions, I judge somewhat uncorrect from a serious speaker-maker selling different products with the same name.

[ra.ra]

On 4/24/2019 at 6:17 AM, Tunedguy57 said:

Personally I prefer the sound of 4x: more smooth and natural human voices.

This is a great point about the human voice range and midrange frequencies. While my AR-4's do not quite match the 4x or 4xa (nor the AR-6!) in LF extension, there are times when the AR-4 is the preferred speaker - - - like when playing female vocals or jazz (vocals, strings, brass) at moderate volume levels. 

[Pete B]

@Giorgio AR  Those are nice pictures of the woofers.

Does anyone know the correct part number for the AR-6 woofer?  There is mention

on here that the Xmax was quite high, higher than the other 8" woofers:

 Also was there a ceramic magnet version of the AR-6 woofer?

[Carl]

On a related topic, the tweeters on my AR6 are blown. Anyone know a good modern replacement. My AR6 has the 10uf cap and resistor.

[Giorgio AR]

Hello, before stating that your tweeters have failed, if I were you I would check first (with the help of a good magnifying glass) carefully the wires that carry the signal to the coil: it often causes oxidation, visible for a greenish color , these may have an interruption along the course of the cone (you have not specified the type of tweeter of your AR6) and flange... with a lot of patience and dexterity, they can be repaired by replacing the interrupted and oxidized section of cable.
If the cables are ok, check the Aetna pots which always cause corrosion they can interrupt the signal (most of the time they are easily recoverable and here you can find the recovery solutions) or if they cannot be recovered you can find the correct NOS replacements at an enthusiast's price by great JKent.
Finally check and if it is the case, replace the capacitors.
If the tws are definitely dead, post a picture of yours to help you find the perfect pair!

[Carl]

I did some close investigation with my ohmmeter and discovered that voice coils in both tweeters were good. It turned out that on each speaker one of the fine wires that run from the connection lugs to the coil was broken just were the wire runs from the frame to the edge of the speaker cone.  I was able to lift it from the cone and remove it from the frame and loop the ends together then apply some solder. Taped the wire in place to the frame.  All is good and working fine.  The wires are very fine so I had to use watchmakers tweezers to work on them.

Thanks Giorgio for your advice, you got me going in the right direction.

[Giorgio AR]

On 3/15/2023 at 2:31 AM, Carl said:

you got me going in the right direction

Hi Carl, happy to have given you the correct input, it's really a pity to throw away a tweeter for a "small" problem, I personally fixed 3 of them, 2 of which from the AR6...all working well for the next few years, but above all they are the originals, the next best thing to our beloved AR speakers.

I'm posting the photos of the last AR6 tweeter that I saved... there are four good welds and the restoration of the connection cables to the contacts... the protective tape repositioned as originally; the tweeter is like new throughout.

The glue used has yet to dry and become translucent... then the repair becomes indistinguishable!