RS-4b Crossovers- Should I Recap?

Azriel

AK Subscriber
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Hey guys,
I've finally finished replacing all the bad/mismatched drivers on my RS-4b's (one bad midrange, 4 incorrect woofers).

Now that I'm listening to them more seriously, I'm finding things I don't like. The tweeter sounds quick and clear, like it should. However, it's the only driver that sounds good to me. The midrange is unengaging at best, and at worst, it sounds like there's a blanket over it. The bass is slow, sodden and wooly. Very boomy and muddy with no extension. I'm shocked at the bass the most. I never thought 8" woofers in a sealed cabinet would sound so boomy. I don't really hear anything below probably around 80hz, but what is there is very peaky. Overall, the speakers just sound dull and flat, but with a very bright treble. The tweeters sound completely disassociated from the rest of the speaker, much like the old infamous Heil AMT speakers. Both l-pads are set right in the middle and are working fine.

I'm wondering if the crossovers would benefit from a recap? If not, I don't really see myself keeping these speakers. They're just not very revealing. If I do recap, what would be the best way to do it? I can't even see the crossovers right now because of all the batting. I'm also not sure how to remove the batting without ruining it, as it seems to be secured somehow.

Hope I didn't waste my money on these. So far, I'm quite underwhelmed by them.

EDIT: I also wanted to add some information about my system. I'm powering them with an Integra AVR. It's from around 2008 or so and has a setting for 4 ohm speakers, which I am using. I run it in "Direct" mode, so there's no signal processing, crossover, equalisation, etc going on. It's being fed by the optical output from my two Marantz CD 300 disc changers.
 
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In the interest of experimenting, I started playing around with the speaker positioning. I moved them a little further apart from each other, and about 6" closer to the front wall. This lowered the midbass hump a bit. The midrange still is what it is. I'm wondering if that's just the sound of these domes. Are they known for being very soft/dull usually?
 
I never experienced what you are with my 4's. As a matter of fact I think the mid is a little on the bright side and the bass is pretty tight. You would be welcome to come and hear mine for comparison. They are not "b's" but have all the same drivers and the crossovers have never been touched. If they sound much different then maybe something is wonky in the xo's. We live around 45 minutes northwest of Philly.
Jim
 
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First to try is make sure you try the woofers wired in series, not paralell.
this is a common mistake, as Infinity doesn't really spell it out, but most models w/ 2 woofes should be in series.
Make sure you clean the volumn controlls, and that they are working. This could be you mid-range problems.....:music:

Also, how much stuffing is in your cabs? You want them FULL. not stuffed like concrete, but nice and "fluffy full". Some of the old infinity stuff will settle into big hard clumps, tear it apart and re-fluff it. If you were starting w/ fresh, I 'd at say least three bags into one cab. Ymmv. :D

my two cents Stu
 
Thanks for the advice everyone. Jim (slimpikkins), I'd be interested in hearing yours sometime that's convenient for you. It's always fun sharing a mutual interest.
 
Add one more note to the 'in-series' wiring of the woofers... they must also be in phase. Input wire (from the output of the crossover network) goes to the +. Then the - of that woofer goes to the + of the next woofer. Then the - of the second woofer goes back to the - binding post.

Almost all crossovers benefit from a recap, done properly. Things that are already high-end obviously won't. But, things this age and originally cost-constrained almost always do.

Remember, though, don't judge your speakers until your system is set up properly and your speaker placement within the room is optimized as much as possible for your particular living situation. Even the best speakers, carelessly shoved into a corner, will not sound worth a darn. This process involves a bit of learning and dedication, but is the single best tweak you can do for your music system and often doesn't cost a dime. Sounds like you did some experimenting with this already. May I suggest a very methodical approach instead of experimenting? Proper speaker placement should really be characterized by a lack of experimenting.

The ones you see in my avatar are not 100% optimized; that's because the component racks are in between the speakers. I didn't want to do this, but I became outlet-constrained. The actual placement of the speakers, though, was very carefully and methodically done. World of difference.

Did those midranges take any damage? How's their condition?

G~
 
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I also noticed that my RS-IIIa's are very sensitive to the room placement. Particularly the bass. When kids are around I have them in the corner on the left (see my avatar), and the bass is quite boomy. So I can not really play them loud there at all. DUring the day I move the speakers to the 'home office' position, and the bass and imaging is much better. I am sure this positioning is not even close to ideal, but it is best I can get with the space I have available.

Regarding midrange, I have not noticed any issues with that. Midrange and tweeters work together well IMO. The only issue has been bass, and it very much seems to be a problem with the non-ideal listening space in my case.
 
Thanks for the advice everyone. Jim (slimpikkins), I'd be interested in hearing yours sometime that's convenient for you. It's always fun sharing a mutual interest.

Just pm here. I'm somewhere on this site allmost every day. Be glad to have you over.

I would take Geoff727's approach. My speaker placement in my small room is similar to his avatar. The RSIIb's look way to big for the room and too close together. I will never go back to a monitor/satillite system in my sound room. Large speakers can sound nearly optimal in a small room with a few low cost tweeks and patience. I have my own room for my "big" stereo and music comes first in that room. It's a luxury to be able to move furniture out and big speakers in...

One other thing to do is just let those speakers play for a few days straight. They may have been in storage for a while and the crossovers need to just be used again. New foam surrounds take a couple weeks to sound their best.
Jim
 
I'm powering them with an Integra AVR. It's from around 2008 or so and has a setting for 4 ohm speakers, which I am using.

Also, try your Integra in the 8 ohm setting. The reason that I recommend the 8 ohm setting, is that most modern AV receivers limit power and current output, when switched to the 4 ohm setting. The 4 ohm option is there to protect the receiver, from too low an impedance load, and it's not a switch to select a more capable setting for 4 ohm speakers.

Just don't crank the volume too loud. Play music at 'safe' levels, until you get an idea of how warm your receiver will get, when using the 8ohm setting.

And as others have stated, play with placement. But, if you do recap, I think your time and effort will be worth it. Solen, Erse, and Dayton Audio have some nice sounding, inexpensive capacitors. Maybe add a good, low value bypass cap, to the mid and Emit caps too. Helps improve the sound, without the high cost of paying for ultra-expensive caps. Bundling multiple lower value caps, to add up to the needed value, can be cheaper too, than paying for one larger part, as well.

Good luck!
 
Thanks for all the additional suggestions. As always, there's a great group of people here. I decided to switch them over to my "A gear"- the Conrad Johnson PV-2AR tube preamp and Parasound HCA-800II power amp. I was really curious how they'd sound with this gear.

Unfortunately, there's still in the same room, sharing it with the Frieds. So, needless to say, positioning is not ideal. I think the first thing I need to do is get them positioned properly, then I can make a more accurate assessment. I will say one thing, for the most part, they're pretty non-fatiguing.

-Jon
 
I'm happy to report that I seem to have found a good position for the RS-4bs. These speakers are really growing on me. I'm listening to Genesis' The Lamb Lies Down on Broadway album, and they really sound great. Revealing without being harsh. That's a delicate balance to strike.
 
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