What are these Woofers?

[Charles218]

One of the many projects that I am currently working on is a pair of 4AX's. They are quite clean and the only issue is that they do not have original AR woofers. I had one extra original to use and I'm trying to find another so that I end up with an authentic set. The replacements that were in the boxes actually look quite nice and I am wondering if anyone recognizes them from the attached photos. Stamped on the rear of the cone is the number "203039"

[xmas111]

They almost look like they're from the AR9's. Lower Mid-range.

John

[RoyC]

Charles,

Those are AR's "universal" 8 inch replacement woofers. According to the code on the label, they were manufactured in late 1983.

They will work quite well in the 4x as well as most other AR 2-way speakers equipped with 8 inch non-plastic cone woofers (AR-4xa,6,7,18, etc).

Roy

[Charles218]

Roy,

Armed with the info that you have given above, I wandered through the forum to see if I could find more details about these drivers. I am puzzled on a couple of things that I found. The driver number on the sticker on mine is 200001, however many of the posts that I read talk about at 1200001 driver. Do you know what the difference is?

Also, from the close-up in my original post, you can clearly see "561 8345". I assume the 83 is the year of production and I thought that the 561 was the EIA number, but went I looked it up it said *'nventa Electronics Co. ltd., Taipei, Taiwan." I must be missing something because the label also says "Made in USA"

Have there been any subjective listening test comparing the original AR woofer to the 200001 replacement driver?

Charles

[RoyC]

Roy,

Armed with the info that you have given above, I wandered through the forum to see if I could find more details about these drivers. I am puzzled on a couple of things that I found. The driver number on the sticker on mine is 200001, however many of the posts that I read talk about at 1200001 driver. Do you know what the difference is?

Also, from the close-up in my original post, you can clearly see "561 8345". I assume the 83 is the year of production and I thought that the 561 was the EIA number, but went I looked it up it said *'nventa Electronics Co. ltd., Taipei, Taiwan." I must be missing something because the label also says "Made in USA"

Have there been any subjective listening test comparing the original AR woofer to the 200001 replacement driver?

Charles

Yes, the "83" is the year, and the "45" is the week of manufacture. Whatever "561" meant in those days, it was not connected to a Chinese company. I've always assumed it was AR's EIA number, as it is found on many AR speakers. The "1" in front of an AR part number usually means it was manufactured by the now defunct Japanese company, Tonegen. Almost all AR drivers were eventually manufactured by Tonegen, so most of the old driver part numbers eventually began with "1". There was probably overlap with old stock.

That woofer is essentially the same ceramic magnet 8 inch driver used in most AR speakers with 8 inch foam surround woofers from the mid 70's (later AR-6, AR-7) well into the 80's. There were versions of it with different dust caps, but otherwise the same. Sonic and measured differences are minor in my experience. The only difference I have actually heard is a slightly different midrange character compared to the alnico magnet/cloth surround AR-4x woofer. By the end of production, however, the 4x was also using a version of what eventually became the "universal" woofer.

Roy

[ra.ra]

Hi Charles:

As a former Ann Arbor guy myself, I hope I can help you here. Any chance you are connected to tmadblue, the AR A-P pot restorer (AK's nerdy little kid)?

I, too, have been curious about the particulars of AR's 8" woofers as well - - - see my fairly recent post below. Two things in your post are curious to me, so I'll bring them up and maybe we can get further commentary and clarification.

First, AR never produced a 4ax speaker - - - the lineage was AR-4, then AR-4x and finally AR-4xa. So I'm not fully certain which speaker you are referring to, but I will assume it is the 4xa. The 4xa utilized the later tweeter, of course, but was released with both cloth and foam woofers. Further, this model had versions with the tweeter pot control (10 mf cap) as well as the tweeter switch control (6mf cap, maybe?).

The second thing that perplexed me here was Roy's comment that some late model 4x speakers may have had a foam surround woofer. I have never seen this configuration myself, but I certainly believe that this was possible since there was often a sharing of available parts as models morphed from one version to the next. Lastly, the parts lists below from '77 and '79 support Roy's comments about the part number nomenclature.

http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=7897&hl=

[Charles218]

Well, if tmadblue owes you money, I don't know him, anything beyond that and I can tell you that he is my son. We started this speaker, vintage audio hobby about ten years ago, he is now twenty-one.

Yes, I was ahead of myself, I meant AR-4X, that is what I have. These are speakers that I found at one of our local second hand shops and was at first disappointing to see that they did not have original AR woofers. I did note though that they didn't appear to be junky generic replacements so I wanted to check here on this forum to find out what they were.

Since I only have one original woofer, with cloth surrounds, I think I will put new foams on these and see how they sound. I have three or four pairs and will compare these to the versions with the cloth.

Go Blue!!!

[ra.ra]

Yeah, I sort of thought you two might be sharing the same household.......... Your son's lengthy AK writeup on the pot restoration is a terrific document.

OK, so it's confirmed that you've got 4x's and not 4xa's - - - and as Roy has noted, these universal woofers just might have been factory originals. Once re-foamed, they should serve your purpose very well. Like you, I've got a few pairs of 4x's, and when one original tweeter died fairly recently, I chose to re-build that pair of 4x's into my pseudo-version of 4xa's by using a more recent tweeter and adapting the crossover (see post #77 in thread below).

http://www.classicspeakerpages.net/IP.Board/index.php?showtopic=7431&page=4

I wanted some slightly different pairs of speakers to compare, so I understand if you do choose to use your 001 universal woofs with new foam for comparison. However, if you prefer to stay with cloth surrounds, it turns out that I have one woofer that I could part with - - - see pics attached, and let me know if this interests you.

Hmmmm - - - Ann Arbor second hand stores - - - makes me wonder if the White Elephant is still around, or if the annual Kiwanis Sale still takes place.

[Charles218]

Actually, I would prefer to install drivers with the cloth surrounds as the 200001's don't feel authentic to me. I need to go down and check the one woofer that I have, will then PM you and see if we can work out a deal.

I don't remember the "White Elephant", but the Kiwanis Store is now open every Saturday morning instead of the once or twice a year sales. Last month I picked up a pair of Rogers Studio Monitors for $20. That was the price for one speaker, the other they tossed in the recycle bin because it wasn't working. I was able to retrieve it from the bin, along with a pair of Klipsch KG4's.