Infinity RS-1Bs Restore

bored184

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The other day I picked up a pair of Infinity RS-1Bs. You can see more about that endeavour HERE. The goal is to restore these back to their original glory.


Question One: External Crossover
Are their any current production external crossovers that will work or do I need to find the original? I plan on picking up an original when the opportunity presents its self at a reasonable price.

Question Two: Internal Crossover for Midrange/Tweeter Panel
Are their any modifications that need to be done to the crossover that have been reviewed and excepted as improvements? I plan on doing a recap anyway.

Question 2.5: RS - I vs. IB
The back of mine says RS - I but they look like Ibs. I am guessing these are an earlier model. If these are earlier then the Ib can the crossover be made to Ib and if so is it worth it?


Question Three: Woofer Tower
Am I to assume there is a crossover in the bass tower or does the external crossover control those?

Project List:
Good Cleaning
EMIMS and EMIT replace or repair. (Started this already)
Recap the crossover in the tweeter/midrange panel
Refinish all wood services

Photos will be posted soon.
 
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Will try to answer some of these:

1. In theory you can use any active crossover that has the correct adjustments, but the only way you'll get the benefit of the servo is with the original.
3. There shouldn't be any crossover inside the woofer towers.

You've probably seen that there's someone currently selling the crossover on ebay, but IMO his price is way too high. We've discussed this seller in other threads on this forum.

Let's see some pictures!
 
Question One: External Crossover
Are their any current production external crossovers that will work or do I need to find the original? I plan on picking up an original when the opportunity presents its self at a reasonable price.

An after market active crossover would work, but it would just do basic signal routing. It wouldn't have the built-in EQ and servo control, that the original Infinity has. Some of the current DSP units could probably be made to emulate the original crossover, but you'd still need to know the the original's EQ curves.

Question Two: Internal Crossover for Midrange/Tweeter Panel
Are their any modifications that need to be done to the crossover that have been reviewed and excepted as improvements? I plan on doing a recap anyway.

Your planned recap should be fine. Some also rewire the speakers too, with better and newer wire. The old Monster cable wiring (IIRC), tends to degrade over time.

Question 2.5: RS - I vs. IB
The back of mine says RS - I but they look like Ibs. I am guessing these are an earlier model. If these are earlier then the Ib can the crossover be made to Ib and if so is it worth it?

I really think your speakers are RS-1's or A's. The A's had black bullet dust caps on the woofers. The later 1B's used a clear bullet dust cap. Also, Infinity-classics.de has info on the different versions, and the crossover variations. It's in German, so open the link in Google, and Translate it to English.

http://infinity-classics.de/models/Reference-series-1+b-2-10+A+B-1981-86/index-Reference.htm

The wiring and crossover schematics are there too:

http://infinity-classics.de/technik/manuals/RS_I_technical_sheet.pdf

Question Three: Woofer Tower
Am I to assume there is a crossover in the bass tower or does the external crossover control those?

No crossover in the bass column. Mid/Highs on the upper panel, and bass crossovers and controls on the external unit.

Project List:
Good Cleaning
EMIMS and EMIT replace or repair. (Started this already)
Recap the crossover in the tweeter/midrange panel
Refinish all wood services

:thmbsp:

Photos will be posted soon.

:D:banana::D

Good luck, and keep us posted!!! :yes:
 
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Considering what some charge for the original Infinity RS-1A/B crossover, you may be better off (monetarily speaking) picking up an active crossover and an EQ unit. While this pairing still doesn't completely replace the original crossover, it will get your newly required speakers up and running.

For reference (not mine):

http://knoxville.craigslist.org/ele/5147588288.html

But, there's also Dr. Marks, on eBay. Compared to the crossover in my Craigslist link, his prices don't seem too high. And while I think the Dr. means well, and is a true Infinity enthusiast, he's also a business man too, and wants to make a profit. So, if you go that route, make sure that you know what you're buying (fully functional, mods, etc.?), and Get-It-In-Writing!!! :smoke:

P.S. Read this too. Some good tips in the review.

http://www.stereophile.com/floorloudspeakers/485infinity/#Ey7UlrGjZUshSOMh.97
 
Wow $1495! that guy spent to much time on the glass pipe you could generate one from scratch for less off the schematics including some one building you a custom PCB and a case!


That was my thought too. Lay out a PCB, and stuff the parts by hand. It's not like the crossover contains proprietary coded Eproms. It's all opamp based. Nothing that complicated! Heck, point-to-point anyone...??? :D
 
i would avoid an EQ and try to find a good bass boost compensation unit. the Marchand Bassis would be an excellent option (in some ways, might even subjectively improve over the stock servo circuit), but you'll have to purchase new most likely. not at bad deal at $650 by any means.

any ol' active crossover will work for the bass, and for the mid/hi panels, you can just put the proper-valued capacitor in series with the RCA cable or jack to accomplish the same thing the stock HPF switch.
 

This crossover is for the Infinity RS 2.5/RS 4.5 and yes, the price is way too high. It was included with the 4.5 and optional for the 2.5 and as far as I know was specific to only these two models. I use one to horizontally bi-amp my RS 2.5's with two Soundcraftsmen amps. All three can be seen in my avatar.

Here is a link to the users manual compliments of Klaus.

http://www.infinity-classics.de/technik/manuals/RS 2.5 - 4.5 Crossover Manual.PDF

The schematic is also available if anyone is interested.
 
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Here is a photo of the midrange/tweeter towers. The bass towers are in a corner of my audio/repair room and it takes two people to move those. I will try and see if I can get a better shot of those. A family shot will not be possible until I am done restoring them.




Question Four
Can anyone with a set of these take some measurements and photos of the dust covers? I will need to make a set for all four towers.

Question Five
I pulled all the EMIMs last night and tested them. Any ideas why on both towers the third down from the top are both shot and trashed compare to the others.
 
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Question Five
I pulled all the EMIMs last night and tested them. Any ideas why on both towers the third down from the top are both shot and trashed compare to the others.

The Emim, third down from the top, is the only Emim used as a midrange. The upper two, and lower four are all wired together, and crossed over as lower mid/midbass drivers. So, if over-driven, that third Emim takes the full brunt of the abuse, and generally would be the driver damaged first. Also, if all of your Emit's are intact, the previous owner's amp wasn't driven into clipping. Shear volume took out those mid's! :yikes: As such, good thing you're already doing a full restore, since it appears that those speakers were driven pretty hard! :sigh:
 
Jonathan if you are considering a different active cross over you might consider raising the cut off of the mids a bit. Ive heard the cut off to the woffer is at 150hz .. not sure of the slope
 
The Emim, third down from the top, is the only Emim used as a midrange. The upper two, and lower four are all wired together, and crossed over as lower mid/midbass drivers. So, if over-driven, that third Emim takes the full brunt of the abuse, and generally would be the driver damaged first. Also, if all of your Emit's are intact, the previous owner's amp wasn't driven into clipping. Shear volume took out those mid's! :yikes: As such, good thing you're already doing a full restore, since it appears that those speakers were driven pretty hard! :sigh:


I was afraid of that, the story I was told is as follows. These were picked up at an Auction four days before my purchasing them. The guy had them hooked up to one of those cheap all in one stereos. I don't know if he used that on them a lot but there is no way that little thing could handle these with out clipping.
 
Nice score! These speakers have an excellent reputation! I think you should restore them with the correct, original servo crossover.
 
Another thought. While I know the OP wants to restore his RS-1s himself, one man that I would recommend that he contact is Bill LeGall. Bill owns and runs Millersound. One of the best speaker repair companies out there. Plus, Bill is an Infinity expert too! He owns 2 pair of IRS's, which he personally restored. Bill even went do far as to balance match his Emim's, in each left and right high frequency column. Matched the impedances, so each left mid matched each right mid! Now that's dedication!

http://www.millersound.net/contact.htm
 
Careful. No eBay links allowed in general discussions. Against the rules. Plus, you need to note that the linked item doesn't belong to you. No self promotion.

Otherwise, I agree. RS-1A/B's deserve their original Servo crossover. It's part of the design.

I didnt know about no ebay links, so my bad. But self promoting... huh?? Im not the seller... its Magicmarksy!
 
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