Jab

Excellent glue information, Thank You Kent!

Thanks Kent, excellent information. The reason I plan to wait until the shop is "just so", is for me rather than the speakers. Lighting is now reasonable, but not what I want. I have a fairly nice 8X illuminated magnifier. I need to pick up an array of cutting and clamping devices. The last time I did this was like 30? years ago with a set of Infinities, and the project came out very well. Will look closely into the various parameters of the glue. Not to disagree, but I'm not convinced it would adhere well to the foam. The paper, certainly. Will put an exacto knife set on my list. There is another factor in play...it's summer. By winter I'll have the shop in good shape, and not be distracted with outdoor projects. Thanks man, John

Searching, I found re-discovered this. That the "replacements" are cheap junk. I am indeed an inveterate tinkerer, but have agreed with the advice that the best path forward with these is new foam surrounds. I may go so far as to purchase a reference microphone and see how close to the original the rebuild came, and will post results. Don't hold your breath though, 😉 this rebuild isn't going to happen until the shop is suitably re-equipped to do the job well. If it suits any administrative purpose you can close this thread, and I will re-open one to share the rebuild and solicit any tips.

I can't find it now, but that software was public domain. Perhaps someone will remember. These https://www.trueaudio.com/ all have a modest price, but none ring a bell.

Thanks Bill, Understood. Not an acoustics engineer here, but retired EE. From back in the day when we had to take our maths in the math department, similar with mechanics and physics. Remember? The thought occurred to me that if I had found a path to acoustically "similar" drivers, there is PC based software out there to test assembled performance with nothing but a calibrated microphone, then perhaps fiddle with the crossover. Bring the crossover outside the cabinet for tuning, then the whole process might provide a "reasonable" state. Something like this https://www.daytonaudio.com/product/1116/umm-6-usb-measurement-microphone (for which you can download serialized calibration files) (if you can trust them?) could take advantage of this wonderful age we live in where the cost of reasonable test equipment has come down. But sourcing replacements with some assurance of similarity proved to be a PITA, so, it looks like this winter I'll just replace the surrounds and call it a day. 😉 Though, the process of confirming basic performance might be fun. Advanced performance characterization I would argue, with sadness, requires exceptional hearing, ear training, and sound field experience. This is why it only makes sense for me to take it so far.

They should indeed easily tolerate the 1/3 watt a 1.5V battery would produce. I can also apply a low frequency sinusoid, which should (if I am thinking this through correctly) keep the travel at the center of it's range on average. The surrounds are still in transit. No fault of Simply speakers. They have been marvelous. The point is I have plenty of time to get set up properly. My former workshop must be restocked.

Thanks Stimpy. Forgot all about Ren and Stimpy. Loved them.

OK, y'all convinced me. Surround kits are on the way from Simply Speakers. Nice folks. Super helpful. But.... I forgot to order dust caps, so this aint over yet! Could someone please post a link to the re-building video? It's been years since I did this on a set of infinities, and damn if I can remember what was involved in getting the dust cap off! Thanks in Advance.

All good advice and suggestions. Aadams suggestion of the https://www.humanspeakers.com/e/parts/001.htm woofers seems the path of least hassle. Though maybe at some point I'll get motivated to pack these up and send them off for re-foaming. I think I just got too used to enjoying my leisure to do it myself. I'll mull this all over, then post a pic or sound file once these are operational again. Thanks All.

A very interesting localized reply. Thank You. Money is not the issue here. I just want advice for a good replacement which involves merely a #2 Philips and possibly wire strippers. 😉 My thought is AR's cabinets are solid, and they used the best drivers of the day. I am interested in "very good" (not perfect) drivers of today.

Thank You Aadams. So, the implication would be if they were replaced, it was with AR replacements.....whatever that means through time. So, whoever was in control of the AR stickers decides what they mean. Any pics of old, old AR stickers and what they were stuck on to would help. This is a mystery trail.... kind of fun. The penned in R/L, "M-ish"/R. and R/R are interesting. I wonder who penned them. So my guess is the first line is part number, the second line is 561? (mystery to me) and date code from the day, which was YYWW, Year and week of year, so these were made in 1980 right before Christmas. Then, good old MADE IN USA! Made in USA or not, I think these speakers are nothing particularly special. The cabs are solid, worth an upgraded set of drivers if a suitable match can be found.

I take your points. I was referring to changes in cone mass. These just feel very brittle, as if they had lost moisture content, or some other outgassing or changes in paper chemistry had occurred. Also, these did not seem to be high quality speakers, hence my comment the Daytons might be better. And so, I removed them and found a clue......it appears they may already have been replaced by a company called Digital Perugia. The frames seem a bit thin, but perhaps they were par for the course back in the day. So, Dayton Audio is just about like the Pittsburgh and Chicago brands at Harbor Freight? 😉 I may have to be realistic and give up on domestically manufactured speakers. Given the photo's, do you have any opinion if these were indeed AR replacement drivers, or would you say some substitute? The picture of the three of them has the midrange in the middle. Thanks for the assessments.

RoyC, If the transplant works OK, pre-pay shipping and packing and these are yours. Four woofs and two mids. Not the rear seals, only the speakers. I pulled this one out and 360 degrees of nothing. I'm thinking the Dayton Audio replacements would likely be better, perhaps a lot better.. Re-building these, with 30 years of drying? The cone mass and stiffness would not have any semblance to the original, or maintain an original sound. Whatever the original sound, it is lost to time. Really what I have here are two solid boxes. Will build on that. Will pull the damping material out, measure, and go from there.....

Duly noted, but this is one of those cases where perfect is the enemy of good enough. Upper bass and mids even with some dips and peaks. Which I may tune a bit if it's intolerable. Worst case, if it is truly intolerable, I go speaker shopping.

Thanks genek. Yea, will pass on Chinese. I may end up refoaming as plan B. But I'm in central Italy, so just finding a specialty shop is an impediment. https://www.simplyspeakers.com/acoustic-research-speaker-foam-edge-repair-kit-fsk-8.html Plan A is I did find a couple of drivers I can get here through an Italian Dayton Audio distributor, which will make them a totally different beast, but really all I want to use is a boxcutter and screwdriver and see what we get. Of many choices, I'm leaning this way: Woofers: https://www.daytonaudio.com/product/25/dc200-8-8-classic-woofer-8-ohm Midrange: https://www.daytonaudio.com/product/1152/pm220-8-8-neo-wideband-midbass-driver Don't ask me why. There's a lot on my plate for some weeks to come, and I just want to do an easy fix, even though fidelity will change. The one benefit of having some hearing loss. 😉