Trying to find suitable RS-4000A replacement woofers

hatrack71

distracted by everything
Well, I found a pair of these loudspeakers with the original boxes in pretty nice cosmetic condition. One woofer is frozen, the other moves but scrapes. Both show an impedence of 4.7 ohms. Neither has any output at all. Kinda weird, maybe the crossovers need work too? Does anyone know the specs on the 902-2666 woofer? I need to purchase a suitable pair of 8's with the same parameters. Not having any luck finding working originals. These must not have been very hardy drivers.

On a side note, I actually remember these speakers from when they were new on the market. A dealer here in town carried Infinity and I remember wondering why these particular speakers sounded so good with these awful fake wood cabs and crappy speaker connectors.
 
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Some here won't agree with me but I say since you're replacing both woofers and the RS4000's are "collectible" Infinities, go ahead and use any 8" 4-ohm Infinity woofers. At one time I put some Infinity IMG woofers into a pair of RSe's and they worked fine.
The only ones I would stay away from are the woofers from the SM series Infinity woofers. They seem to be designed to be more efficient at the expense of low bass.

Look on eBay. It shouldn't be too hard to find a pair but you may need to re-foam them.
 
That makes sense but unless they were clear poly, I can't imagine why it would make a difference. They don't seem like they are all that special of a woofer but they aren't junk either. Am I wrong? Are they special? I do remember liking this model for it's super accurate high end. I have read up on adding bracing from front to rear and that makes sense given what I remember hearing. These things were way under rated. By Infinity the most. I mean why would they use such crap speaker connectors with drivers of this caliber? They seem so out of place as does the vinyl veneer. Because they opted for those options, when one looks at these, they can easily be mistaken for white van until you remove the grills and spy that little emit.

Anyway, I am still looking for the parameters on this speaker if anyone knows off hand. Sensitivity, fs, etc... I really doubt I will source originals unless someone really convinces me to do so. Thanks for the reply by the way RickyM.
 
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Did you check if the woofer magnets had shifted? That can cause the problems you have described.
 
Check the magnet as stated above. If there's no noticeable problem there and since the woofers aren't any good the way they are carefully remove the dust caps with an x-acto knife and see whats up. If they have bottomed out many times there could be a burr on the voice coil that could be removed with said knife. Or the aluminum voice coils could have been over heated and have warped. This can sometimes be corrected by rolling a smaller round oject like a Sharpy pen on the warp to smooth it out. If there is still a small amount of scraping you would just have to pull the surround off either the basket or the cone (or just by new surrounds), shim the vc with some light card stock and then reglue. I would not give up so quickly on those woofers.

Forgot to mention to pull the drivers out and sound test them without the xo. I would think the unfrozen one will produce some sound. With the woofer out you can also try to unstich the frozen one since you will be able to push up on the cone from between the basket supports.
Jim
 
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Check the magnet as stated above. If there's no noticeable problem there and since the woofers aren't any good the way they are carefully remove the dust caps with an x-acto knife and see whats up. If they have bottomed out many times there could be a burr on the voice coil that could be removed with said knife. Or the aluminum voice coils could have been over heated and have warped. This can sometimes be corrected by rolling a smaller round oject like a Sharpy pen on the warp to smooth it out. If there is still a small amount of scraping you would just have to pull the surround off either the basket or the cone (or just by new surrounds), shim the vc with some light card stock and then reglue. I would not give up so quickly on those woofers.

Forgot to mention to pull the drivers out and sound test them without the xo. I would think the unfrozen one will produce some sound. With the woofer out you can also try to unstich the frozen one since you will be able to push up on the cone from between the basket supports.
Jim

Okay, thanks for that. Should I just use a battery for sound? I don't think I want to hook them up to any amps I have. Are you saying tht the crossover could be possibly bad on both lower registers?
 
Got the dust cap off but still can't ascertain anything as there is a black phase plug in the way. Does that need to come out and how?
 
Got the dust cap off but still can't ascertain anything as there is a black phase plug in the way. Does that need to come out and how?

The clear phase plug needs to come off too. The glue is most likely dry and brittle so try genty prying it off with your x acto knife. Or carefully cut through the glue all the way around. Try not to let any of that dry glue fall into the voice coil.

Testing for sound i just test mine with my shop sound system. I have pair of allegator clips wired to my "b" speaker terminals on my receiver.
Jim
 
The clear phase plug needs to come off too. The glue is most likely dry and brittle so try genty prying it off with your x acto knife. Or carefully cut through the glue all the way around. Try not to let any of that dry glue fall into the voice coil.

Testing for sound i just test mine with my shop sound system. I have pair of allegator clips wired to my "b" speaker terminals on my receiver.
Jim

Okay. I'm still not brave enough to hook up to anything I have. I don't really have an amp I want to risk blowing with a problem load or possible shorted driver. I know they read resitance but I don't trust them. The phase plugs are black. Maybe these have been refoamed?

At any rate, a kind AKer has sold me a nice pair of originals. So I can experiment with these under no stress. I am guessing no matter what, I have to get the magnet off the driver to be able to inspect the voice coil right?
 
Good luck with your repair!

I picked up a pair of these at Goodwill almost a year ago,I saw them sitting there and they do in fact look like cheap things until I pulled off the grill and saw those emits, I figured I should hear those once in my life so I brought them home, hooked them up to my amp in the testing area. I laid them on their backs and applied low volume, and one woofer was blown. I completely disassembled it and it was crushed like an aluminum can. I shopped around for replacements but folks want 70 bucks each for these things. I used them as speaker stands , stands for record crates &c.
I put the woofers on my e bay "interests I follow" it took about six months but about a month ago two came up for sale and I ended up snagging them for $19.00 for both. :D
I have a speaker wire connected to an amp and I use it to run low volume "noise" / FM static or a 50Hz tone that I have on a CD through them. They both produce sound with no rub...You can also do the battery thing and the woofer will move but does not produce sound with that method.

I finished the refoam job last night and will be reassembling them today sometime. I will hook them up and hope they sound good with no other issues.

My old notes say that 902-7298 can be used for replacements , these are black IMG - Injection Molded Graphite from such as SS2004 infinities. ( I bought a pair of those for 9 bucks and refoamed them to learn how to do it, I also added bracing &c. with some help from fellow AK'rs.)

This also from my old notes
RS 4000
Introduced: 1988

Dimensions: 57 x 32 x 25 cm

Bass: 1 x 20 cm
 Polycone
Mids: 1 x Polycone

Highs: 1 x EMIT

Suggested for amplifiers with: 25-125 Watts per channel

Frequency response: 45 Hz - 45 kHz

Crossover frequencies: 800 Hz, 3500 Hz
6 ohm
Nominal Impedance 89db @ 1 watt / 1 meter

Suggested price (pair):* $ 470

pic of my old blown woofer voice coil

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have fun!
 
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Good luck with your repair!

I picked up a pair of these at Goodwill almost a year ago,I saw them sitting there and they do in fact look like cheap things until I pulled off the grill and saw those emits, I figured I should hear those once in my life so I brought them home, hooked them up to my amp in the testing area. I laid them on their backs and applied low volume, and one woofer was blown. I completely disassembled it and it was crushed like an aluminum can. I shopped around for replacements but folks want 70 bucks each for these things. I used them as speaker stands , stands for record crates &c.
I put the woofers on my e bay "interests I follow" it took about six months but about a month ago two came up for sale and I ended up snagging them for $19.00 for both. :D
I have a speaker wire connected to an amp and I use it to run low volume "noise" / FM static or a 50Hz tone that I have on a CD through them. They both produce sound with no rub...You can also do the battery thing and the woofer will move but does not produce sound with that method.

I finished the refoam job last night and will be reassembling them today sometime. I will hook them up and hope they sound good with no other issues.

My old notes say that 902-7298 can be used for replacements , these are black IMG - Injection Molded Graphite from such as SS2004 infinities. ( I bought a pair of those for 9 bucks and refoamed them to learn how to do it, I also added bracing &c. with some help from fellow AK'rs.)

This also from my old notes
RS 4000
Introduced: 1988

Dimensions: 57 x 32 x 25 cm

Bass: 1 x 20 cm
 Polycone
Mids: 1 x Polycone

Highs: 1 x EMIT

Suggested for amplifiers with: 25-125 Watts per channel

Frequency response: 45 Hz - 45 kHz

Crossover frequencies: 800 Hz, 3500 Hz
6 ohm
Nominal Impedance 89db @ 1 watt / 1 meter

Suggested price (pair):* $ 470

pic of my old blown woofer voice coil

attachment.php


have fun!

Dare I ask how you got the magnet off?
 
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The 8" infinity woofers I played with had a black cloth dust cap and a smaller clear one under it. If you can get them off and look under them you may see the problem and beable to flatten out the wrinkles. If you play around with this stuff a lot it is good to have an old receiver around to test speakers and take with when you go to buy used speakers.

I never removed a magnet to fix mine so I'm not sure how you would go about it without damaging things.
Jim
 
Dare I ask how you got the magnet off?

If I recall correctly remove all old foam and snip the wires to the terminals, and the cone pulled right out.
I tried to straighten the thing out but it was so mangled and torn up that I did not think that putting it back together would yield good results, thus the hunt for the replacements.

Here are some pics.

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Great pictures asterion. Much appreciated.:thmbsp:

Thanks and you are welcome. Just passing on some of the good audio karma that I have been a recipient of since finding this forum.:thmbsp:

Here are the speakers,re-foamed,re-assembled and each one tested individually, now I have to make some room for them somewhere and give them the Rock n Roll acid test.:D

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Well, I took off the cone and you won't believe what I found. I wish I would've taken a pic. I guess the circular burn mark is still on the basket and on the spider. The voice coil came completely out of the gap, broke off the cone and welded itself to the basket at the same time burning the spider material. An inch off center of the gap even. Wow! someone was abusing these big time. And get this, it still maintained resistance in the end- the leads held- unbelievable! Way too mangled to do anything to try to fix- the copper was crushed like a tin can- flat.

But, this got me thinking. Can a guy just put a new voice coil and spider on these and still utilize the original cone and phase plug and basket? Are the parts available? Honestly, it's looks like everything was glued on with something alot like Gorilla glue.
 
Well, I took off the cone and you won't believe what I found. I wish I would've taken a pic. I guess the circular burn mark is still on the basket and on the spider. The voice coil came completely out of the gap, broke off the cone and welded itself to the basket at the same time burning the spider material. An inch off center of the gap even. Wow! someone was abusing these big time. And get this, it still maintained resistance in the end- the leads held- unbelievable! Way too mangled to do anything to try to fix- the copper was crushed like a tin can- flat.

But, this got me thinking. Can a guy just put a new voice coil and spider on these and still utilize the original cone and phase plug and basket? Are the parts available? Honestly, it's looks like everything was glued on with something alot like Gorilla glue.

Infinity used some tough adhesives that is for sure! I guess that some folks that bought these should have bought the SS2004's for their BIG BOOMY BASS. I had to tame those down with extra bracing &c. .
These RS4000 are great so far with the lows and mids and balanced well with the bass, I guess some folks really do want "LOUDSPEAKERS" and tried to find it with VOLUME.

I have seen some videos on U Tube of folks that wind up voice coils but I do not think it would be worth the effort to save the woofer once it has been destroyed like that. I think I read where you got some replacements from a fellow AK'r?
You could also just keep an eye out for some that come up in speakers that often will go on sale cheaply on craigslist or e bay. I saw some a while back
(different model same driver) on craigslist for 10 or 15 bucks but they were too far away to make it practical to go get.
 
Infinity used some tough adhesives that is for sure! I guess that some folks that bought these should have bought the SS2004's for their BIG BOOMY BASS. I had to tame those down with extra bracing &c. .
These RS4000 are great so far with the lows and mids and balanced well with the bass, I guess some folks really do want "LOUDSPEAKERS" and tried to find it with VOLUME.

I have seen some videos on U Tube of folks that wind up voice coils but I do not think it would be worth the effort to save the woofer once it has been destroyed like that. I think I read where you got some replacements from a fellow AK'r?
You could also just keep an eye out for some that come up in speakers that often will go on sale cheaply on craigslist or e bay. I saw some a while back
(different model same driver) on craigslist for 10 or 15 bucks but they were too far away to make it practical to go get.

I hear you and yes the original replacements are on the way. Did you add the front to back bracing between the woofer and mid inside the cab? It's supposed to help a lot. I was gonna use a couple 2x2's and do it in two spots and then run run a brace perpendicular from side to side. How are you liking your RS-4000As so far? Mine will be together by the middle of next week. look to be in the same condition as yours- almost new looking.
 
I hear you and yes the original replacements are on the way. Did you add the front to back bracing between the woofer and mid inside the cab? It's supposed to help a lot. I was gonna use a couple 2x2's and do it in two spots and then run run a brace perpendicular from side to side. How are you liking your RS-4000As so far? Mine will be together by the middle of next week. look to be in the same condition as yours- almost new looking.

I braced the cabinets on the SS's not on the RS's. I used some round closet rod as this was recommended by another AK'r. With the closet rod you can use those little round hangars on the inside,glue them in place making it easy to set the brace in,glue it to the hangar then add a screw or two for additional support. I also experimented with coating the woofer surround with a thin coat of that black rubbery adhesive in order to hold back the bass on that model, they also have a rear firing port that early versions of that model did not have so they work well in the guest bedroom and visitors can spin records and CD's and enjoy music on something other than their I-phone speaker. I do not think that controlling boomy bass is needed on the RS's as they are very balanced through the frequency ranges.

I am very pleasantly surprised by the speakers. I have put them in a small bedroom, although not the ideal space for sitting and listening to music I have been testing them with a range of musical styles and so far so good.
They also have an adjustment knob on the back/crossover I have not played with that yet but just have it set in the center setting. The Emit tweeters do live up to their reputation - yesterday I put on a record from back in the fifties - Persuasive Percussion on Command Records to hear the woofers perform and it is all good. Today on the menu for them is a run through with some Coltrane,Monk,Bach and Beethoven and then perhaps a little Live at Leeds to really wake 'em up. Right now though it's Dylan on my Klipsch and Mirage stack in the Wreckord Room. (If you ever spot some Mirage M460's snag em...can one really have too many speakers?)

I will at some time test the infinity's out in a bigger space but for now I am happy that I have completed that project and the end result was a good one.
I hope your project works out as well! :music:
 
Ahhh, I see. So there were SS-4000s and RS-4000s? I see yours do in fact use a different but similar Emit. Mine use the Emit K and they don't have a port in the rear. So you are saying the RS-4000 doesn't need bracing? Just the SS series. I read somewhere the the RS-4000As do in fact benefit from bracing as well. Wonder if I am confused.
 
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