Stimpy

Just trying to be thorough.

I think I'll just stick with Rust-Oleum satin black. That makes my brain hurt less...!

Eastern Chem-Lac 37038 Lusterless Black H-8241. It's in the AR-9 Cabinet Plans that Ken uploaded. Cabinet Drawing 1 references Drawing 6, which lists the paint, in Note 6.

The stock Unicon brand of capacitors, in my 58S's, still seem to sound fine. So, if your 10pi speakers have those, you'd probably be good for a while. If Callins, I'd upgrade (replace).

Ooh, I like those better. They look more like my AR58s speakers. It's a shame that more of the European styled speakers weren't available here? Or were they? I'm definitely no expert. Plus, those make me wonder how the 58s models would look with the AR91 woofer trim rings?

There was an AR-8B, that used a 6.5" woofer. Maybe that was it?

Thanks! That's pretty much what I've been thinking too. Especially since it would be easy to unwind an inductor, and order a new cap. Now, I just need to get this out of my head, and onto paper and birch plywood! I tend to 'plan' forever, before any action physically happens. I aggravate myself sometimes, by being so slow.

Hey Guys, I want to build a center channel speaker, to match my AR90's. I'm not sure why I want to do this, other than I 'think' it will be fun. I already have some of the drivers (a pair of AR18 woofers, a pair of AR90 LMR mids, and a AR90 UMR dome), and a spare AR90 crossover, I can use. I might even have a set of AR91/92 crossovers, if I can find them, that I could try too. But, my main issue is finding a suitable pair of drivers, that when wired together, will match the impedance of a single LMR. Does something like that exist? Did AR ever build a true 8 ohm mid or woofer? Any thing from 4.0 to 8.0 inches would be fine. I'm thinking that 2 smaller drivers, would work better, as this should improve dispersion. I know I could change out an inductor and change capacitance, to compensate for an impedance mismatch, if needed. But, i have the crossovers, which I'd like to use as-is, if possible? Plus, I'm still debating the layout. I'm definitely going to use a tweeter/dome midway centered pair, with the tweeter over the mid, as in my 90's. But, then what layout; W LMR T/D LMR W, or W T/D W? I guess that hinges on if I use a 4-way or a 3-way crossover board? Any suggestions? I know I'm already crazy, so that suggestion won't be anything new to me! Thanks!

Wasn't that a Frank Lloyd Wright design?

Those look awesome...! Especially the AR-94Si's. I love that redesigned sock-less look. Well done. Plus, this whole thread is pushing me to start looking for AR-18's. Once I finally finish the refurb on my AR-90's, that may be my next AR journey.

Doesn't the AR9 bass section, use 2 stacked coils? That's listed as "never do this", according to the coil layout pictorials (#8)...! Can (and should) those coils be separated and remounted?

Here's a later crossover picture, with better coil orientation. I'm not sure either, what'll improve? But it's easy to try, and what can it hurt?

I did exactly that on both boards. I stood up the left coil, of the large inductor pairs, and stood up the blue coil too. I guess I need to update my picture?

I went a little over board on my 90's. But, why not? I think the speakers are worth it.

I read on another board, about bypass capacitors, and why they work. This is a direct quote, from Danny Richie of GR Research, on why he feels bypass caps improve the sound of a crossover: "Think of a capacitor as an energy storage device. The larger it is the more it can store. Also the larger it is the slower the rate of discharge. Think of it as power in... charging up... then discharging. The time involved in that process represents some smearing to the audio signal. Faster discharging caps are cleaner sounding. That's one of the reasons a Sonicap (for instance) sounds so much cleaner than so many others. Also, the fast discharge caps really give you the space between notes and that can be a big improvement in sound quality. Now the tiny little by-pass caps are so small that they hold nearly no charge at all by comparison. It is basically power in and power out. So they tend to help discharge the stored energy of the larger cap when by-passing them. So you have a big needed cap value but you take on some of the fast discharge rate of the smaller cap." I don't know if this helps, but it's one possible explanation to consider.

The tweeters appear to be a better match for AR9's or 90s. But maybe they'll work? The mids look like the mids Ken Kantor designed for his AR303 design. So again, maybe they'll work? Unfortunately, not much else out there to choose from.

I'd try and get all the tweeters and mids rebuilt. There's several speaker experts around the web, offering such services. But if you do go with replacements, be sure to keep the stock drivers, for future resale value. As to replacement tweeters, most recommend the Hi-Vi QR-1 tweeter. It requires an additional inductor, but is supposed to sound very good. Hi-Vi Mod I'm not sure about replacement dome mids. I'm not sure any exist? If the mids aren't repairable, I'd use dome mids from AR91s or AR92s. Then I'd pop the horn from the 91/92 mid, and replace it with the mesh screen and felt from the 3a's. It should sound pretty close to stock (I think, I hope).

Oh yea, I have my AR90s and a spare set of crossover boards for the 90s too. During the recap, I rebuilt the spare crossovers. So, once the speaker refurbs are done, I can pull out the original crossovers, and swap the new boards in. Well, after I did the recap, I set up one of the stock 90s, and then pulled the UMR dome from the other, and hooked that to the new crossover boards. In the A/B comparison, the single dome sounded far, far better than the original speaker. I heard more mids and highs from the one dome, than both the tweeter and dome mid in the stock speaker. Clearer and much more open. Also, there was none of a static type of distortion, heard in the stock speaker, in the new crossover, either. From that alone, the recap seemed a success to me. IMHO.

Oh Boy, this should be fun, and very interesting!!! Recap discussions can get 'passionate', for want of a better term. Some believe that it's best to stick to the original design, and replace electrolytics with electrolytic. Others think inexpensive poly caps are fine, and as long as the correct values are used, sound just the same as more expensive parts. Then, there's idiots like me, that use the best parts 'that they can afford'. A bit different than the best out there, but still more expensive than entry level. Also, what I did, to save a little money, was use as good as I could for the series capacitors, and entry level for the parallel, shunt capacitors. The series capacitors are the 4uF, 6uF, 24uF, and 80uF values. The 8uF, 30uF, and 40uF are the parallel values. I used Mundorf for the series caps, and Axon True Caps for the parallel caps, and E-Caps for the 350uF, in my AR90s. When I had to combine caps for a specific series value, I used Mundorf EVO Oil and Supreme caps. Otherwise, I tried to find the correct values, using a single cap. I'm still working on the restore of my 90s, and I haven't been able to perform a finished audition, but quick A/B tests so far, have been very promising. Finally, there's are a few other members here that have been recapping AR9 and AR90 speakers too. We've discussed our trials and tribulations about the process, amongst ourselves. It's been frustrating at times, but a good learning experience. I hope they'll offer their advise too. Good luck.

Well that's bizarre! It looks to me like someone definitely was in there, as I wouldn't think they left the factory like that. It looks to be an easy fix. Or, pick up a set of 91 / 92 crossovers on eBay. They pop up fairly often. Then you'd have level switches too! And I'd try isopropanol on the glue also. Good luck.

Awesome write up. I love the chart, showing the changes and the audible results. And pictures. Everyone loves pictures! Though, next time, pop-up's would be even better! Nice work.

Well, it's good that you did a decent audition on the speakers. Plus, listening to the tweeters with your ear directly over it, is about all you could do in an owner's home. Kind'a hard to pull out a screw driver and a multimeter and ask to take the speakers apart! But, if you get the speakers, it' going to be bad tweeters, or bad caps, or more likely both. And you already know that the switches could use a cleaning too. As to value and restoration costs, most here feel the AR9s are worth it. That you'd have to spend far far more than what this investment might be, to match the sound quality of the 9s, with a new pair of speakers. So, I wouldn't worry too much about exceeding their resale value, as you probably won't want to sell them, once they're 100% functional.

The tweeters use an 18db per octave crossover, so I would hope they haven't been blown. It would be very unusual for both tweeters to be dead. As such, did you try more than one source, and several recordings? The reason that I ask, is the 9 and 90 cross fairly high up to the tweeters. They're almost super tweeters. So, is it possible that the tweeters were working, but the musical selection didn't exercise their range? Too low to notice? Still, for a pair of AR9s, I wouldn't give up so easily. If it does turn out to be defective tweeters, start with a lower offer; maybe around $300/$350. Work up from there. Good luck!

No specific model numbers, other than what's exactly printed on the labels: "Active Partners". AR was bad about that. Some of their designs used model numbers, while others had names. Plus, later in years, model numbers started being reused, due to the notoriety of specific classic models.

Oh yea, read/search through this forum too. There's lots of 'which amp' threads, that are still applicable to your inquiry.