Just bought RS 5b. Was it mistake?

mr_RBG

mr_RBG

Well-Known Member
Just bought Infinity RS 5b from ebay.
It is ebay so I overpaid for them no doubt, but really like how they look and my friend(Infinity fan) bet they will kick my HPM-700 ass easily.
But they need to be refoamed!
Can you please tell me where I can buy good kit for them?
I found one on ebay is it what I need:
"Refoam kits- 10" Infinity w/ bullet dustcap. One PAIR (repair two woofers) - DIY Polyfoam surround replacement parts.
Angle attach to cone -ID 6.813" (173.050mm), OD 9.625" (244.475mm)- with adhesive, and instructions. No dustcap or shims needed or included with center bullet."

http://www.infinity-classics.de/inf...1981-86/Reference-Standard-5B/body_rs_5b.html
 
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I bought a pair of RS 5b about 5 months ago, fortunately they had new foam surrounds. They sound great to me. Clear mids and the highs are spectacular with the emit tweeters. The 10" poly woofer does a great job of providing fast, crisp bass. I'm not even thinking of adding a subwoofer at this time.

I have played them at extreme volume levels without a hint of distortion.

They are my first line speakers, I am ordering some stands 10 - 12" high, with a slight backward tilt. They sound much better up off of the floor.

Get them foamed or DIY, I think you will be very happy with your choice!
 
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I got some surrounds from 'looneytune2001' on eBay. I believe he is a member here, not sure what name he goes by on AK. He always has kits available on eBay. They come with instructions, glue, and a test tone CD so you don't have to shim the cones. He was recommended to me here on AK.

Good Luck!
 
They were just delivered! Very good looking speakers! what can I say..
Just tried them to be sure that drivers work.
I found they are much less sensitive than hpm. I found some posts here that Infinitys are amp killers because their impedance, is it true? Is it save for my Yamaha CA-800 to drive them?
 
mr_RBG said:
They were just delivered! Very good looking speakers! what can I say..
Just tried them to be sure that drivers work.
I found they are much less sensitive than hpm. I found some posts here that Infinitys are amp killers because their impedance, is it true? Is it save for my Yamaha CA-800 to drive them?
Click to expand...

according to the Infinity-classics site, that is adequate power to avoid damage, but not my much. Even if you can avoid damage to the Emits and your amp, I don't see how you could expect optimum performance from these speakers using that power level. I wasn't happy with my (similarly equipped) 6 Kappa Infinity speakers' performance until I began using an amplifier rated at 220 wpc into 8 ohms, but, damn am I happy now. Stand by for further advice, as there are more experienced and knowledgeable Infinity folks than myself here to advise you.
 
mr_RBG said:
They were just delivered! Very good looking speakers! what can I say..
Just tried them to be sure that drivers work.
I found they are much less sensitive than hpm. I found some posts here that Infinitys are amp killers because their impedance, is it true? Is it save for my Yamaha CA-800 to drive them?
Click to expand...

I don't think those have the severe impedance dips that some infinities do, but they do probably get to 3.5-4ohm territory. They'd probably benefit from a beefier amp, maybe a lot, but I don't think you're at much risk as long as you don't connect any other speakers. Just try to listen for clipping / excess distortion when you turn it up. I wouldn't recommend any loudness or other bass boost above low volumes though - that could send you into clipping fast. Does the tweeter have a fuse on the RS5b? I'm sure someone knows.
 
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As others have noted, these are not the worst amp-killers. They don't have the large Watson woofers that suck the power from amps with 1-ohm impedance dips. Still, they'll appreciate getting enough power and will reward you with better sound, when you feed them well. (How's that for anthropomorphism? :D)

Welcome to the vintage Infinity club, and enjoy the ride, er, uh, the music! :music: :D
 
Here is my article on refoaming RS-4b. I did not take off or replace the dust caps, and I would recommend not doing that unless you absolutely have to. Suggestions were to buy surrounds are in the article. Refoaming is easy, and once done you have a pair of great speakers :thmbsp:

RS-4b-surround-19.jpg
 
Nope, the 5b's are not amp killers. But being Infinity sealed box designs, they will still sound best when paired with a robust amplifier of 100-150 wpc that can throw out some current.

Nominal impedance for these is listed as "4 to 8 ohms" as it was for most of the Reference Series speakers of that era.
 
Thanks nice article!
Would like to clarify one thing for me: do I need to put clamps when I use tone generator?
 
Well, you need to hold the surrounds in place temporarily while testing if there is voice coil rub. You do that by playing a sequence of tones, and listening if it sounds OK. It is very easy to hear if there is a problem, and if there is, you simply shift the surround slightly until the problem is gone. There might be other options, but I cannot think of anything simpler than holding the surrounds in place with clamps during the testing and until the glue has dried. The clamps you see in the photo are from the Dollar Tree store chain, and cost $1 for 4 clamps. So all 16 clamps you see in the photo - enough for 4 woofers - set me back $4.
 
So, I refoamed the woofers. It was very straightforward. Thanks for the tips.
Now when they are working I can say that they very very good sounding speakers!
High-mids and highs are just astonishing! The speaker are very dynamic.
Did A/B comparison with my Pioneer hpm-700. What can I say... I was surprised how good hpm-700 are! :) I would not say that they are better than RS5b, in high and high-mid section hpms are bit muddy, but on some material they just outperform Infinity(just listen sax on "Shine on you crazy diamond"). And of course, Infinity are sealed boxes so bass is tight but not so full and filling.
If you ask me I can not choose one. I wish but can't :)
 
run sufficient power into the Infinity pair, and there would be no comparison. powering a relatively inefficient speaker at or near its minimum is no way to make it perform
 
Run them with Pioneer SA-8100, Yamaha CA-800 and Technics SA-500. Technics sounds just amazing with them!
 
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