Guest bweinel Posted April 19, 2004 Report Share Posted April 19, 2004 Well, After letting my AR-90s collect dust for about ten years I finally got around to refoaming the woofers and lower mids this week and made a somewhat concerning discovery... I found that the 3/4" tweeters in my units are apparently mismatched. One is a 1200029-1 and the other is a 1200011-1. Since I am the original owner of these units and have never replaced one, I can only assume that it must have happened at the dealership before I purchased my speakers.(These units were floor demonstrators at the showroom where I purchased them... so its quite possible that they were damaged and repaired prior to my pruchasing them.) I pretty sure that the 1200029-1 is the original part number and the 1200011-1 is a replacement unit as it is labled with the red "replacement unit" warranty tag on the back as others have described here. I guess the real questions I have are twofold: (1)Is the 1200011-1 tweeter a correct replacement unit for this speaker or, as I suspect, did someone just stick in a part that they had on hand to fix a bad tweeter? and then (2)Where can I find a 1200029-1 tweeter to match my original and get the speakers back to a matched set? Link to comment Share on other sites More sharing options...
Guest Bret Posted April 19, 2004 Report Share Posted April 19, 2004 In message #2710, Tom Tyson discussed these two tweeters. His response to me is quoted below:Written by Tom Tyson:"Well, as you know, the AR #200029-1 is the 4-ohm, 3/4-inch-dome .tweeter designed for the AR-9, 90, 91, 92 and 915, and it was optimized for the 7 KHz. AR-9 crossover. The AR-91, for example, has a 7.5 KHz crossover. The tweeter has a 2 KHz fundamental resonance (well below its operating range), and has a ferro-fluid voice coil. The magnetic circuit has a total flux of 21,000 maxwells and a flux density of 18,000 gauss, but these figures are largely meaningless to anyone other than a speaker designer. It also has a recessed "horn" of sorts that increases the efficiency at the higher frequencies, but very slightly decreases off-axis dispersion at the highest frequencies compared to the flush-mounted tweeters. The AR #200011-1 was an earlier design, 3/4-inch-dome, treated-fabric, flush-mounted designed for the AR-10Pi and AR-11. I am not certain if the earliest versions (brownish-orange) of this tweeter had ferro-fluid cooling; later "B" versions definitely did. Just as with the AR-9 tweeter, it is also a 4-ohm tweeter, has the 2 KHz resonance, same magnet assembly, but operates at a 5 KHz crossover. In the end, therefore, the two are not really interchangeable -- despite the similarities -- any more than the AR-10Pi tweeter is interchangeable with the AR-3a tweeter.--Tom Tyson"Hope that was some help.Bret Link to comment Share on other sites More sharing options...
roundhome Posted April 20, 2004 Report Share Posted April 20, 2004 Hello I have the 11-1 as the replacement tweeter for the 10,11,9,90,91,92,915,58sthis is a 1992 AR parts listJim Link to comment Share on other sites More sharing options...
Guest bweinel Posted April 20, 2004 Report Share Posted April 20, 2004 Hi Bret,Thanks for the reply and the repost of Tom's original message on the AR-90 tweeters. That actually helped quite a bit and confirmed my earlier thoughts as to it being an incorrect substitute for the original. The 200011-1 in my speaker is the brownish-orange design. After closely listening to them tonight with a variety of music, I can definitely say that the two do not sound the same. The speaker with the 200011-1 seems to have a muddier sound than the speaker with the 200029-1. As to why it was used as a replacement in the AR-90 for the original part number, I am still not sure. Could have been a cost saving measure (i.e.: they had that model on hand already.. or AR wasn't making the exact replacement anymore and the 200011-1 was specified as being the closest replacement. I have seen this happen in the radio/electronics business in other areas where vendors, in order to cut inventory and manufacturing costs, use generalized replacement parts.)I guess now I will need to see if I can locate a source for the 200029-1 tweeter so I can get a matched set.Many thanks for the reply.-Bill Link to comment Share on other sites More sharing options...
Guest Bret Posted April 20, 2004 Report Share Posted April 20, 2004 >The 200011-1 in my speaker is the brownish-orange design.<Bill, that's a rarity and if you had two of them would be quite a pair to have.As far as I know those were ONLY used in early production AR-10pi's and haven't been available for a long, long time.eBay has been the best place to get the replacement for the 200029-1s I've found. They seem to be a lot more common than the 200011-1 particularly if that's the one I think it is.Look in the Forum library and download the 10pi brochure and see if that looks like the tweeter you have.Bret Link to comment Share on other sites More sharing options...
Guest Bret Posted April 20, 2004 Report Share Posted April 20, 2004 >As to why it was used as a replacement in the AR-90 for the original part number, I am still not sure.<For the same reason you climb a mountain; Because it's there.I suspect it was what was "in the back" when they needed a tweeter.Bret Link to comment Share on other sites More sharing options...
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