Infinity RS-IIIa - Worth restoring, or not?

Well, they would have had a hard time shorting through the electrical tape and 3" of air I put between all the loose wire-ends before any power went into the cabinet. Just curious, but wouldn't a direct short trigger an immediate shutdown rather than waiting almost a minute after I turned up the volume? I may be a newbie to audio electronics, but the concept of a short circuit is not new to me. I've rewired half my house and it hasn't burned down yet. [Sorry, but I'm terrible with emoticons, so I don't know which animated GIF I should insert here; please advise.]
Depends on the amplifier and the quality of protection circuitry.
Some amplifier manufacturers like Bob Carver used to demonstrate his amplifiers by applying a direct short to show their durability.

Since the wires were wisely taped up to avoid a short perhaps your amplifier might not take to well to a three ohm load(Emit) playing music vs just testing:dunno:
(May I suggest a butt plug):thumbsup:
Also:needpics:
 
Well, I have been taking photos, but I guess I won't be posting them here. Since this forum has turned rather rude and hostile, I'm out of here.

I can't say I blame you! I'm not sure why a member chose to treat you so poorly, I actually considered contacting the moderator during the course of this thread. Usually this is a friendly, welcoming place for newbies.

"All audio, no attitude" please!
 
I apologize for being a buttplug.
However I do believe as he stated, he has no interest in this hobby and has little interest in learning a new hobby at "this stage of his life" other than to milk info out of friendly, eager to help AK'ers, or so it seems.
I'm not sure where the OP was "treated poorly" "throughout the course of the thread" as to squeal for a moderator..
Perhaps I was a tiny miffed when he stated poo-pooed my suggestion on testing the Emits in cabinet as a "flawed idea" but he was hardly abused by me.
We will see if the OP stays on as a newby or is "one and done" after friendly AK'ers get him up and running.
Fine and welcome to AK in any case.
 
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I can't say I blame you! I'm not sure why a member chose to treat you so poorly, I actually considered contacting the moderator during the course of this thread. Usually this is a friendly, welcoming place for newbies.

"All audio, no attitude" please!
OMG, really?
 
I tested my QLS-1 last night with an on line tone generator. They crossed over at 4,000 Hz in the middle setting, 4,400Hz on high and 3,600Hz on low. I can't verify how accurate the free tone generator actually is... Maybe someone with more knowledge than me could math out the crossover parts?

How are you testing them? Hook up a laptop to your system or a small test amp, receiver, etc. and use Audacity to generate sine waves. You can specify exactly what frequency and the length of time it plays. Use a good meter that can read frequency accurately and connect the leads with clips to a tweeter, or if the crossover is out, the terminals on the high frequency output. If your tweeters aren't getting signal till 4khz, your speakers might be sounding somewhat muted and dull. Especially if still using the original dome midranges which should possibly be retired as they're old and tired. When I replaced the mids and midbass drivers it's like I have new speakers. That and rebuilding the crossovers as well.
 
I see a fellow Infinity owner who has tried some of the suggestions in an attempt to fix his recently acquired Infinitys.
Not sure I'd call that "no interest in this hobby" or "little interest in learning."
He's acknowledged a couple of his weak spots, nothing wrong with that.
We all had to start somewhere.
I'd like to think with our help he'll have those classic Infinitys up and running before too long.
He has learned about some testing methods and some troubleshooting which could help him in the future.
I am glad to offer what little help I can to a "good cause".
 
That one.



Well, I have been taking photos, but I guess I won't be posting them here. Since this forum has turned rather rude and hostile, I'm out of here.

Feel free to PM (start conversation) with me if you have any questions.
I'll try to help if I can.
 
Gary,

If you're still here, I'm not sure if anyone answered your earlier question about ohm ratings and how they are added up in a speaker. The crossover divides the various ranges and sends them to each driver, and although this looks like loads in parallel, it's really not, because any given frequency presented by the amp is only going to come out of one driver. Except around the crossover frequencies, but those are controlled so that impedance is fairly constant over the entire range. The 'nominal' impedance (8 ohms or whatever) on the back of the cabinet is sometimes an average, sometimes the lowest across the audio range, depending on manufacturer.

Even if an EMIT is only 3 ohms, I can't imagine that the amount of power actually required to play one at a reasonable volume for testing would provide such a load on a healthy amp that it goes into protection.
 
After rereading the last couple pages, I am still not clear what could be wrong here that would cause the amp to go into protection on one speaker and not on the other.

I hope you are minimizing play time on those un-refoamed woofers and that you have them laying on their backs. The surround helps keep the voice coil centered and letting them flop around with no surrounds can make it rub to the point of shorting. On their backs there will be no sag.
 
May be informative, might not be...the only published (that I've seen) review about my RS II's shows they hit 3 ohms at 5Khz and are barely above 2 ohms from 6Khz on up to about 20Khz.
http://audiokarma.org/forums/index.php?threads/rs-ii-lab-test-article-w-full-measurements.621716/
That is all in the area that my EMIT(s) run in (they cross over at 3 Khz).
Obviously the RS IIIa may have a totally impedance curve (crosses over at 4Khz), just mentioning for general informative purposes.
 
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I don't know how common that is with speakers, but I have the impression that most have their impedance dips at much lower frequencies. One saving grace here is that most of the power required by a speaker is in the bass, and the least is in the treble. I saw some numbers recently on that but I don't remember them. But suffice it to say that the power required to achieve a given db output at 100 Hz is generally much higher than at 10,000 Hz in most speakers. If the OP's amp was cutting out at mid-volume running just the tweeter, it's hard to imagine the tweeter could draw THAT much current if it's working OK.
 
Tox, I always thought the same, and it may be true, lower freq. would have the impedance dips.
I posted it because OP said only his EMIT(s) were being driven when his amp acted funky.
Granted the RS IIIa curve is most likely different but at least one Infinity model did have a big impedance dip in the treble range if the magazine curve is correct.

Google shows the infamous Kappa 9 dips way low at around 30-35 Hz and again around 7Khz.

Maybe the OP's amp/receiver just doesn't like low loads IF INDEED his speakers dip way low in the EMIT range?
Even if it's just one channel, is it possible there is a problem with his amp/receiver?
Would a DC check at the speaker outputs give any clue to the problem?
 
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As per the OP.
".....And if a new amp will be required to power the RS-IIIa speaker,
then there is no point in me putting time into them..."

unbridled enthusiasm?
 
After some well intended, wise suggestions of trying a different amplifier...
" disconnecting everything in my in use setup and putting it back together later. Neither option very attractive."
more enthusiasm
 
Keep kicking it, I think I saw it twitch.
Don't be rude.
I think that may have been you;)

I feel bad I'm associated with someone bailing on all the enthusiastic Ak'ers that contributed to this dead horse of a thread, one in which I tried to contribute with my opinions based on the statements the OP made about the quite narrow guidelines and effort he was willing to give to get them up and running, and one in which the OP is the one that got snarky toward me , imo.
 
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Is it me or has the OP rewritten some of his posts and removed some questionable remarks? I swear I read something about "golden years".

Anyway, if the OP gets the speakers working and lets somebody know how they compare to those AR-15's I'd like to hear it. I had some AR98LS to play with and didn't think they sounded as good as my Kappa7's but that's my opinion and I may be biased. The 98's just didn't have the top end. I was hoping to hear how the OP liked Infinity, and feel let down he left so abruptly.

To the OP: Good luck sincerely!

Mark K.
 
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