69AMX390

I have a set of AR3a that came with one early style cloth woofer and one late style fiber/paper woofer. My serial numbers are pretty low and close together (3A12967 and 3A13019). I am thinking the one woofer was changed. I will attach some pics of each speaker and crossover. The magnets are like those in my pics. How can I tell if crossovers are different? Seems funny that my serial numbers are 43 apart and I got and early and late style speakers as a set. That would mean that AR did the change between my serial numbers. Does anyone know approximately what serial numbers when the change was made?

I have went back and read through the old posts presented in this thread, as well as current. Great topic and previous answers. I am sure my PS Audio will drive them pretty well. It does well on AR 90's I am currently running. Before I posted this thread, I bought a pair of Adcom 555 MKii amps. I knew they were bridgeable. I should have done more research, or posted a question. Besides increased distortion in bridged mode, the manual, that came with amps, does not recommend low impedance loads (4 ohm and less) while bridged. So, I guess plan B on those amps. Can use one for AR 90's or set up another system. I have a pile of amps, seems like good preamps are a lot harder to come by.

That could definitely be something to consider. I have been trying to factor in very expensive service on the older amps. That is definitely a good price. It is a class D amp. Although class D is coming on strong, I have never heard one in a good system. I will research more. Maybe they have a trial period? I could buy and give it a chance. It would be a big change from the heavyweights I have been running since 1978. Would love to play side by side. I have 2-Parasound P5 preamps that would allow me to set up 2 systems side by side. I have done it with big PS Audio amp and a Parasound HCA-1000 that I have. 200 watts compared to 125 watts. Huge transformer/caps compared to smaller. The 72 pounder wins. The HCA-1000 is a good imaging amp, and well detailed, but the old PS Audio has the low end grunt that just seems punchier and faster on the bass. I am sure the big amp was twice the price (new). It is power hungry and not energy efficient. I have considered having to the PS Audio serviced. I have found the schematic, but no service manual. It would have to be local. Shipping falls into freight category due to size and weight.

First and foremost, I would have never have thought of biamping. But, the AR 9's came with that option. I assumed it must be better. All the comments are good, and appreciated. I did read each and give them some thought. I can see that bridging and biamping are potential problems. I wasn't really thinking bridged. I was thinking using my big PS Audio amp for low frequencies (like sub). And a higher quality amp for the detailed sounds(mids/highs). I was wondering how I would keep the output of the speakers at a balanced volume. I was thinking gain controls on at least one amp. Now I see problems with volume, phase, imaging, and other unknowns. Since this a problem, then I will have to go to plan B. If bridged, I definitely see where unmatched amps will cause problems. Phasing, timing etc. The music could be out of synch, or even blocked by noise canceling. Bridging is definitely not a good option for me. I have always liked powerful amps. Still have my Pioneer SX-1280 that I bought new(which I just dropped off to get a total recap/transistor replacement). It is tempting to hook it up to the AR 90's and see how it sounds. But, I know it will not take the low impedance of the AR speakers at higher volumes. There is too much temptation to want to turn up. So, I will have to pass on a smoke test. Plan B: Since I have AR 9 and AR 90, I will need to buy another big amp. I was thinking Aragon 4004 MKii. It is 400watts at 4ohm. I am also open to other amps, if someone has a favorite that works well with AR 9's. Budget of 1k. So, most likely used.

My main question was to biamp, or not. Which has the best sound? The schematics of horizontal or vertical biamping were new to me. Has anyone tryed monoblocks on AR 9's?

The AR 9 is biampable. Which way do most prefer. True Biamp: Is it best to use one amp for the lows and one amp for the mids highs? Could I use a big solid state for lows and solid state, or a tube amp for mids and highs? How big of a tube amp would be needed to reach full potential? Or, have a bigger beast of an amp to drive both lows, mids, highs. My preamp (Parasound P5) has 2 outputs. That would be a plus for biamp. Currently using AR 90's with a PS Audio 200CX. It is 200 watts/8 ohms, 400watts/4 ohms and 1000 watts at 1.5 ohms. Seems to have plenty of power for these. When I get my AR'9s recapped, I will need to buy another amp, or 2 if biamping. Any suggestions would be appreciated.

I did the trade for AR 90's. Cabinets are a 9.9/10. They came with all the original boxes and packing. I got them unthawed and hooked up. They sound awesome. I am sure they are keepers. Don't mean to bash the Klipsch. I had second thoughts before I traded. Maybe I had not given them a fair chance. Since I have only listened to them through a PS Audio CV200, I switched amps with a Parasound amp I have. I know it has good imaging. The Klipsch still were lacking imaging and dynamics. Maybe they need a tube amp? Not sure, but they are history.

I just had the opportunity to trade a set of Klipsch Heresy II for a beautiful set of AR 90's. Perfect cabinets, all drivers refoamed, new caps, a bunch of original AR 90 sales brochures, sales receipt ($900/1980) and original boxes. Original owner for 40 years, second owner 1 year, and now I am the 3rd. The guy that had them could not power them. That is why he traded. He wanted Klipsch because easy to drive. No problem, I have a couple of big amps to run them. Can't wait to get them hooked up. I had the Klipsch for a few years. They came with new Crites x-overs. They got loud as hell, but always seemed fatiguing, even a lower volumes. Detail was missing. Just a big soundstage. My thoughts, horn drivers. If horn drivers were that good, they would be in all speakers, instead of stadiums. Anyways, need help to get them out of the back of Jeep. Hopefully tomorrow my son can help.

I think I have the amps covered. At least with my oldschool setup. I have 2 amps to choose from. Preamp is a Parasound P5. Plan A. PS Audio 200CX that is an amp from yesteryear, but a beast. It is rated at 200 watts/channel (8 ohms) and 400 watts (4 ohms) and over 1000 watts at 1.5 ohms. Plan B. Aragon 8002, which is a little newer. It is rated at 125 watts/channel (8ohms) and 250 watts/channel (4 ohms). I can use either one, or both to biamp. PS Audio for low freqs and Aragon for the mids/highs. I will probably have to use 2 different circuits in the house to power them.

PT Doug. "Had all drivers tested and built the crossovers to match each speaker, with a flat +/-1.5 db response. " Can you enlighten me with equipment used and how to match crossovers to each speaker? Don't the resistors fine tune? I was assuming most would say they reuse the inductors. Not a deal breaker. It looks much easier to build everything on the bench, instead of inside speaker.

Thanks to another member ,I have obtained original drivers to replace both non working upper midrange and 1 tweeter and 1 woofer. So, next step is crossover rebuild. I have a good background in electrical theory. There are so many choices on capacitors. NPE, film, poly, etc. I am just trying to make speakers sound as good as new, if not better. Does anyone have a cookbook recipe for AR 9 crossover update/upgrades? I realize not all size capacitors with exact uf are available. To obtain correct value multiple capacitors grouped together, in parallel, to obtain correct uf needed. From what I have read, this could possible change the ESR, which in turn could alter the sound. Has anyone reverse engineered capacitors and resistors to get the correct x-over frequency and ESR's needed? Any thoughts on bypass capacitors included in cookbook?

I have read for hours on this subject. I realize this topic has beat to death. There has to be a happy medium between zip cord and super expensive wire. Parts-Express has various sizes of wire. I would assume there has to be something a little better than this Chinese wire. I am open to size suggestions, as well as a better quality alternative, just not $8/ft Kimber Litz wire. An improper solder joint with Litz wire would be way worse than cheap wire. Just need a quality wire with good coating/insulation to prevent oxidation and produce good sound.

I purchased a pair of Bozak 300 that were upgraded to 302, in the past. A learning experience. Wrong bozak mids and wrong bozak x-overs. Anyways the original wiring is long gone. I have purchased correct bozak mids and tobin upgraded crossovers. I do not want to start a wire debate. Is there something better than parts-express hookup wire? I assume it is just run of the mill Chinese wire. I just want a good quaility wire with good insulation. I am not looking for Kimber Litz wire, or the likes of any of the expensive stuff. Any input on sizes would also be appreciated.

Does anyone have an opinion on whether the new replacement tweeters are of good quality compared to the originals. I realize the originals are old and the ferrofluid could be compromised (dryed up). I guess my questions is what has everyone else chosen to get the best performance. New or used?

Are the tweeters from Midwest speaker the same quality as the originals? I had read they are made in China. Would hate to put Chinese parts in my "made in America speakers" Since any original would be over 40 years old, is an original's quality compromised? I am just looking to do what is best.