My First Infinities

nelsress

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Today I picked up my first Infinity speakers, a pair of RS IIIb's with three woofers needing to be re-foamed, at least, and the other one missing-hope I can find one somewhere, provided the three I do have are still good after re-foaming.

These speakers belonged to a friend of mine and he thinks he still has the woofer but has no idea where. If he finds it, he'll see that I get it. My friend didn't want anything for these and when I pressed the issue, he said he wouldn't take more than $40 so that's what I gave him. I'll get him later as he keeps his eye out for stuff for me all the time so the next several items that he accidentally overprices (which could take a while with him!), I'll happily pay his price on. :)

Before re-foaming, I'll make sure they're not open. I also have to make sure the polydome mid and the Emit tweeters aren't open as well. The piece of foam rubber that surrounds the flat surface around the mid and tweeter on both speakers is rotted and should be replaced. The cabinets are pretty nice and the grills are intact and don't look bad at all!

Also with these I got a pair of RS 3000 speakers in fine cosmetic condition with both woofers needing at least a re-foam. I'll be making sure that both tweeters and both polycell tweeters aren't open on these as well before proceeding.

For a long time I've heard Infinity lovers sing their praises and I have to say I'm psyched to give them a listen, after restoring these two pair. Rebuilding the crossovers of both pairs appears to be in order as well, based on what I've read so far.

Both pairs are still in my van so hopefully on Monday or Tuesday I'll be able to get them into my shop and start testing and exploring these speakers. Once out of the van and into the shop, I'll get some photos. There's a wealth of information on AK about Infinity speakers in general, it seems. From what I've read, the Phase Linear 400 that I am preparing to do a White Oak Audio full comp modification on should be a perfect match for the apparently power hungry RS IIIb's.
 
Congrats, RS-IIIa/b's are fantastic all around speakers IMO. They are not particularly power hungry, my current Onkyo A9070 (clean 140 wpc at 4 Ohm) seems to be a perfect match (whereas 9070 runs out of power driving RS-IIs), never running out of power.

Notice also this 5b review article w/ full specs. I have not seen any lab test results for IIIa/b's so this is the closest I am aware of if one is interested in full specs for RS-IIIa/b:
http://www.audiokarma.org/forums/showthread.php?t=617733
 
Thanks Seppo, I appreciate both your insights and the attached related review. I'm anxious to hear from the Infinity guys who have done restorations on these and similar Infinity models as far as hints, tips, and tricks. What's the best source for surrounds for the woofers, is the foam "deadener" piece surrounding the mid and tweeter available, what's the best way to get it off, etc., etc.

In one of the Infinity resto threads someone mentioned using Boston Acoustic or another brand surround versus a generic one as the generics are too stiff and affect the bass response. Is this a common consensus or just one solitary opinon? I also believe I read that using film caps for the restoration of the crossovers will make them sound a little sweeter, is that accurate as well?

Thanks again Seppo and future Infinity fans everywhere for your input.
 
Great pairs of speakers. The IIIb woofer should be pretty easy to find on ebay. The surrounds from Simply speakers are nice and light. Those are the ones I used in the past. Also used the generic variety and found no difference in sound but they are darker in color. The foam around the tweeter and mid can be scrapped off and replaced. Theres a thread or two where the guys who restored them had great success and they came out like new. If you have trouble finding a woofer pm me and I can lone you one from my spares as I don't live too far from you...
Jim
 
While reading about what foam other guys used around the midrange driver and emit tweeter I found these sheets on ebay. What do you guys think, would this work? I thought it looked more dense than other foams I saw guys using, more like the original that's crumbling away. This link is STRICTLY to get an assessment of the material being sold and IN NO WAY has anything to do with pricing. Thanks.

http://www.ebay.com/itm/5-SHEETS-FO...284?pt=LH_DefaultDomain_0&hash=item233b747d04
 
While reading about what foam other guys used around the midrange driver and emit tweeter I found these sheets on ebay. What do you guys think, would this work? I thought it looked more dense than other foams I saw guys using, more like the original that's crumbling away. This link is STRICTLY to get an assessment of the material being sold and IN NO WAY has anything to do with pricing. Thanks.

http://www.ebay.com/itm/5-SHEETS-FO...284?pt=LH_DefaultDomain_0&hash=item233b747d04

I think the thickness of 2mm is fine. But the material should be open cell to my understanding, and this is closed cell foam.
 
Thanks Seppo, I was reading that thread and have read that most were using open cell foam but I didn't think the original looked like open cell, though it's hard to tell as deteriorated as it is. Thanks again for the input/link.
 
You need to also think what is the physical purpose of this foam, that is, to reduce any diffracted sound waves from the surface. So I would think that open cell forms a more random pattern than closed cells, further absorbing sound and randomly reflecting waves all around. In other words, you do not want coherent diffraction or reflection from the front surface.
 
Sounds like you know a lot more about the properties of foam and sound than do I so I will defer to your knowledge and go with the open cell foam. Thanks for the clarification, I appreciate it.
 
Has anyone of you ever had trouble getting a woofer out of these Infinities? This afternoon I tried my darnedest to get one out of these RSiii b cabinets and it just wouldn't budge! Are they known to use a strong adhesive around the metal outer ring of the woofers? This is the cabinet that is missing a woofer so I could actually get my hand inside and push it from the back and it still would budge. Any hints are greatly appreciated, I don't want to bitch these up if I can help it but they've got to come out so I can re-foam them and recap the crossovers. Thanks.
 
I also scraped away all that crumbly foam rubber around the polydome mid and EMIT tweeter and found a paper-like material under some of it that seems to be coming out from under the driver. It looks a lot like masking tape but it's much too wide for that. Anyway, it also looks as if the foam may have been under the edge of these two drivers as well. Have you all found that to be the case as well? Thanks.
 
Those woofers are glued to the enclosure. I used 2 cm wide sharp chisel to carefully pry them off.

Sent from Tapatalk on Windows Phone
 
Thanks for the glue info and the brochure link. I suppose they need to be re-glued back in since they're not ported. What glue did you use or did you go with a rubber gasket of some sort? Thanks again!
 
Don't tell anyone, but I did not use any glue when putting them back. Just screwed them tight. But others here on AK might disagree with my approach :)
 
The chisel worked wonders and I got all three of the woofers out and got readings of between 3.5 and 3.6 on all three so I'm good to go on that end.
 
The chisel worked wonders and I got all three of the woofers out and got readings of between 3.5 and 3.6 on all three so I'm good to go on that end.

Mortite caulk cord from Home Depot works great for sealing the woofers up tight again. Its cheap enough, works good, and you can get it apart again years from now if you have to.
Jim
 
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