Shoot! Infinity Quantum 2 Blown Tweeters and Pots Question.

:tears:

Finally getting around to installing the refoamed woogers. Got the 1st one done last night, and while trying it out I found the upper Emit tweeter has no sound. (used a full paper towel roll as an earphone, and can distinctly hear the sound from the other two, but the top one has none).

I haven't done a search here yet for other info, but wanted to get this post out for any help I get on what the next steps are to repair these if that's possible. I want to get the other speaker running now to see if any others may be dead.

Another question I have for other Infinity owners is how much effect do the attenuating pots normally have? I've sprayed the 3 pots with contact cleaner and have worked the shaft back and forth. While testing the 1st one, it doesn't seem like they have much effect on the tone. The midbass coupler can be killed completely when the shaft is at both extreme positions, and as soon as the shaft is moved off this position it kicks in the midbass but their seems to be no adjustment range.

The tweeter and mid adjusters seem to make a little bit of a difference, but barely perceptible. Is it possible for these pots, if corroded, to still function by sending the juice to the drivers, but not function as attenuators?

OH, on the sound. I asked my wife to come listen to the one speaker last night on a particularily bassy section of music.......she said it gives you goosebumps.....nuff said

The tweeter and mid adjusters seem to make a little bit of a difference, but barely perceptible. Is it possible for these pots, if corroded, to still function by sending the juice to the drivers, but not function as attenuators?

Click to expand...

I had two pairs of Infinity RS-6000's, and both the tweeter and midrange L-pads barely made a noticeable difference. Regarding the tweeters, I am not sure about repairing them, the etched foil is pretty delicate. I am sure they can be repaired, GordonW would probably know better than me. I have seen replacements on ebay before, wouldn't hurt to look there.

Inspiribomb said:

I had two pairs of Infinity RS-6000's, and both the tweeter and midrange L-pads barely made a noticeable difference. Regarding the tweeters, I am not sure about repairing them, the etched foil is pretty delicate. I am sure they can be repaired, GordonW would probably know better than me. I have seen replacements on ebay before, wouldn't hurt to look there.

Click to expand...

Thanks Inspiribomb, Good to hear what you say about the pots. It would make more sense to me that if there was a bad corrosion problem, they would tend to cut out or not work at all....but I could be wrong on that, and hence the question to get a few informed opinions.

I'll definitely be keeping track of the Ebay auctions now, and other spots (AK :yes: ). These can be quite dear on the $$ I've heard. :sigh:

Should have the other mate fired up here in about an hour....hope she's 100%.

Kencat said:

Finally getting around to installing the refoamed woogers. Got the 1st one done last night, and while trying it out I found the upper Emit tweeter has no sound. (used a full paper towel roll as an earphone, and can distinctly hear the sound from the other two, but the top one has none).

Click to expand...

That’s not good. The three EMITs on the front are wired together and so if the others work, then the problem lies with that one EMIT vs. some place else easier to fix. Just to be sure, try carefully removing it (the EMITs are wired together with very short lengths of wire, some of which is held in place with silicone, so be careful not to break anything), disconnecting one lead, and measure for resistance. If you don’t measure anything, ie open, then your EMIT is indeed bad, but there is hope. Army knows of someone who capable of repairing these drivers, so get ahold of him for the contact information. If you want to do the repair yourself, there’s some info here (http://www.bobbyshred.com/emit.html) about how to fix burnt traces using a rear window defroster repair kit, but I can’t vouch for the quality that will lead.

This is a common issue caused by amplifier clipping thanks to how power hungry these speakers are. Just yesterday, I read some comments by a former Infinity dealer who said he’d refuse to sell the models with EMITs to the headbangers as he was sure they’d clip their amps and blow the tweeters in short order.

Just fyi, if you don’t have enough power just yet even after repair, adjust the tweeter crossover frequency control to the higher. This should help protect the tweeters just that bit longer.

Kencat said:

Another question I have for other Infinity owners is how much effect do the attenuating pots normally have?

Click to expand...

Not much, these are high-end speakers and so the controls are only there to fine tune the sound for accuracy, not as with other speakers where the controls are designed to make huge swings in the sound. In fact, the TOTL Infinities had controls that adjusted the levels by only 1 dB. With these particular speaks, though, the pots should cover a range between 0Ω to 5Ω, but I do now know how much of a level adjustment that works out to be after the crossover.

Kencat said:

I've sprayed the 3 pots with contact cleaner and have worked the shaft back and forth. While testing the 1st one, it doesn't seem like they have much effect on the tone. The midbass coupler can be killed completely when the shaft is at both extreme positions, and as soon as the shaft is moved off this position it kicks in the midbass but their seems to be no adjustment range.

Click to expand...

You might want to pull these pots and open them up to clean them. The midbass seemingly dying is due to the construction of these pots, they’re a spirally wound wire positioned in a ~270 degree arc inside with the ends held in place with brass rivets. These rivets in turn feed through to the two connections on the side. When the wiper, connected to the shaft and the center connection, swipes beyond the wire coil and onto the brass rivet, it loses continuity thanks to the corrosion guaranteed to be on the brass – I tore mine apart last week and they were really corroded, a fault of the design.

Just remove the pots, making sure you mark where the two wires connect to, jic. There should be a U-shaped wire that connects the back ceramic half to the front rusted metal component. With a pair of needle nose pliers, carefully pull the bent tab on one of the sides out of the hole and remove this wire. The pot will fall apart in your hands if you’re not careful. Set the front aside and clean the resistance wire in the ceramic half by first blowing the crud out and then carefully wiping it clean with some DeOxit on a q-tip. Next clean the center contact, the thing that looks like a mini-pizza cutter, as this is another place of corrosion issues – may look nearly black instead of the silverish color before. I used a piece of crocus cloth to get rid of the bad stuff and finished up with. Now, you’ll want to clean the wiper which is surely covered with corrosion from the brass rivets. I did the same with the tip of this as I did with the center contact (crocus cloth and DeOxit). I also very carefully bent the end that contacts the wire of both metal pieces down a tiny bit to adjust for ~27 years of wear and tear. The wiper plates will want to fall off, but the pins on the shaft are differentially sized, so it’ll go on the right way again. On mine, the front metal half with the shaft was badly rusted on a couple, so I cleaned mine up with some Corrosion Block (great stuff, exponentially better than WD-40) to prevent more rust that might flake down onto the contacts again. Once done, just reassemble the same as you took apart.

Kencat said:

The tweeter and mid adjusters seem to make a little bit of a difference, but barely perceptible. Is it possible for these pots, if corroded, to still function by sending the juice to the drivers, but not function as attenuators?

Click to expand...

It is possible, as the spiral wire that composes the resistance element can be shorted by flecks of corrosion, as I found in mine. So, you’ll want to do the above and clean them up.

Kencat said:

OH, on the sound. I asked my wife to come listen to the one speaker last night on a particularily bassy section of music.......she said it gives you goosebumps.....nuff said

Click to expand...

Told ya.

Don’t worry; we’ll help you through getting these back up to spec.
- JP

Howdy JP,

Might be a stupid question here.....but.....what's the best way to get those pots out ? I'm not experienced yet with soldering. DO you use the solder gun to pull the wires off or just snip em and resolder later ? Looks like a b...h to have to solder within the box. Good chance to burn up a bunch of wires or something.

What you say about cleaning up the pots makes sense, especially after looking at someones "step-by step with pics" article on the AR pots (Greyhouse I think ?)

Worst part looks like the extraction of them though.

Also, with one tweeter of the 3 blown, does that make it more likely the other two will go ? Depends if they are in series or parallel I guess. If so I better not play them.

Kencat said:

Howdy JP,

Might be a stupid question here.....but.....what's the best way to get those pots out ? I'm not experienced yet with soldering. DO you use the solder gun to pull the wires off or just snip em and resolder later ? Looks like a b...h to have to solder within the box. Good chance to burn up a bunch of wires or something.

Click to expand...

You just pull the knob off the back and using a small crescent wrench or socket remove the nut. The pot'll pull right out. About the wires, I'd prefer to desolder the wires, with a gun or iron, though I prefer gun for this application as it's quick and I'm less likely to burn or melt something while waiting. Since there should be plenty of wire in there, you could cut the wires off and then solder them back on. Probably better that way as you're less likely to have to fiddle with the wires and iron trying to get the wrap through the hole in the pin to come loose.

Kencat said:

Also, with one tweeter of the 3 blown, does that make it more likely the other two will go ? Depends if they are in series or parallel I guess. If so I better not play them.

Click to expand...

That I don't know as I was lucky enough to have all my tweeters working (knock on wood) when I found my Quantums, the only things in them that were. Normally, I'd say it'd be alright if you cross them over higher and don't push the volume. However, as the three are hooked together, having one not working may adjust the impedance and thus swing the crossover point to someplace where these weren't designed to go. So, I'd not run them until you can get the one repaired, though, it might be possible to stick a 10w resistor of the same impedance in place of the bad one as a place holder. :scratch2: I'd ask someone who knows, such as GordonW.

- JP

Charivari said:

So, I'd not run them until you can get the one repaired, though, it might be possible to stick a 10w resistor of the same impedance in place of the bad one as a place holder. :scratch2: I'd ask someone who knows, such as GordonW.

- JP

Click to expand...

Man, do you know how hard it is not to want to play these things.....AH Well, step by step and I'll be there someday. Dang !!

I'm going to hook up the next one to at least know what all needs doing. I don't think I've tested this at all yet. Cross your fingers for me.

Last time I checked (about 3 months ago) Harman/Infinity had a VERY FEW EMIT elements left in inventory... and the "word from above" was that there would be no more once they're gone. So, I'd recommend contacting them, and ordering an element ASAP, unless you happen to luck up on one online elsewhere...

I wouldn't try to "jumper" the bad tweeter. Just don't play 'em until the tweeter element is replaced. One missing tweeter will upset the impedence balance of the crossover, which may cause a dip in impedence at crossover (which will cause an INCREASE in power to the tweeter at the crossover point) and possibly damage to the other tweeter as a result...

Regards,
Gordon.

GordonW said:

Last time I checked (about 3 months ago) Harman/Infinity had a VERY FEW EMIT elements left in inventory... and the "word from above" was that there would be no more once they're gone. So, I'd recommend contacting them, and ordering an element ASAP, unless you happen to luck up on one online elsewhere...

Regards,
Gordon.

Click to expand...

Thanks Gordon, I will do that. Hope there are some left.

GordonW said:

I wouldn't try to "jumper" the bad tweeter. Just don't play 'em until the tweeter element is replaced. One missing tweeter will upset the impedence balance of the crossover, which may cause a dip in impedence at crossover (which will cause an INCREASE in power to the tweeter at the crossover point) and possibly damage to the other tweeter as a result...

Regards,
Gordon.

Click to expand...

That does seem like the most prudent thing to do. Don't want to blow any more of them.

I just tryed the second one, and luckily all three tweeters are working. Both mids aren't making sound though. The leads look ok, so hopefully this is the pot that is the culprit. I'll check the resistance on each though to be sure; although, when putting the woofer back in, I looked at the pots and there is quite a bit of rust and corrosion evident from the outside.

Looks like some more disassembly and surgery is necessary here.

It's only a hobby....It's only a hobby......(my new Yoga mantra)

Kencat said:

I just tryed the second one, and luckily all three tweeters are working. Both mids aren't making sound though. The leads look ok, so hopefully this is the pot that is the culprit. I'll check the resistance on each though to be sure; although, when putting the woofer back in, I looked at the pots and there is quite a bit of rust and corrosion evident from the outside.

Click to expand...

If one midrange were bad, the other would still work, so it does sound like a crossover issue. The pot is the obvious culprit and pretty much a given to be in need of cleaning if you can see visible rust. I found with one of mine that the rust flaked off into the coils of the wire and onto the contacts inside the pot causing it to cease to work. Go ahead and clean them up as I wrote above and if you want to avoid the rust issue, try treating the metal housing with this stuff. Growing up in a port town, I know from experience that WD-40 and its kin just doesn't cut it when it comes to corrosion/rust, but this stuff is great. Just be sure you spray it from a distance and wipe off the excess, Corrosion Block is an insulator and might interfere with the contacts.

- JP

My Q3s

I Have 2 sets of Q3s and have had the same problems.1 set was fixed by cleaning with deoxit.Mine also has very small effect on sound.The second set had serious corrosion and worked intermitantly so I jumpered them out when I set them up for biamping.I have not been able to find a suitable replacement for the pots.1 set is driven by my Sansui g-22000 and souds excellent,although the protection will trip at about 12 oclock on the vol.Yes it is loud.The 2nd set is driven by Bryston 6b mono amps rated at 500 watts into 8 ohms and 800 into 4 and 1000 watts ea into 2 ohms.This set up really makes em sing.Bass response is unbelievable.Finest speakers I have ever heard.keep at it ,in the end you will be most happy.

1000 watts per channel? I take it you're into low-level listening. :thmbsp: Please, if you have some pictures of what sounds to be an incredible setup, post them up here for the rest of us to drool over.

As to the bad pots, try pulling the bad set and pull them apart for manual cleaning. As good as DeoxIt is, it was insufficient to clean the center contacts on my bad pots. The crocus cloth (real name that it's sold under) and a bit of manual labor is necessary to clean both the center contact and the wiper. Jumpering those pots means you're running the mids and tweeters full-level which is not the most accurate or balanced setting unless you're listening in a rather dead room. Though, you might not notice the ~3dB of level difference the pots do affect.

- JP

Here you go.

This is one of them ,and the set up is different now but shows 1 amp anyway.

Time to Jump!

Not affiliated

Quatum EMIT on the Bay

Several pairs, $114 BIN price.

rstsgsas, there's just something right about seeing one of the bigger Quantum speakers getting all the juice they can take. Must really be something to hear when the music cuts loose.

Clifselina, that auction makes me rather angry. First, EMITs rarely go for that amount of cash, but that's nothing. The fact that some greedy powerseller took otherwise perfectly repairable, rare QLS-1s in good condition and parted them out piecemeal for the greatest cash inlay is outrageous. There's not too many of these TOTLs out there and to see this destruction ... :tears:

- JP

OMG what kind of a man parts out a pair of QLS'S.I am about to cry.Well,I will keep looking.

Regards
Mike

Never clipped

I have never been able to clip these amps .They drive the Q3s to complete house vibrating exctacy.The speakers never miss a beat either.No distortion of anykind .The music just gets louder and louder.I do not listen near those levels ,just putting both amps and speakers thru some workouts to see where the limits were.I folded before they did.

I agree, newoldguy, there's something seriously wrong with that guy or his greed is more than the already high level in the average human. Wonder if we could petition the seller to cease the piece-meal destruction of these fine speakers and sell the unit as a whole for restoration? I've the crossover schematics, so repair should be possible after driver removal. Or, we could find a bunch of wise guys to do some convincing on the seller's part.

rstsgsas, I've read that the tinsel leads on the midrange domes are supposed to suffer from the weakness of acting as fusable links at higher (500 watts+) power levels. Have you encountered this problem? How about bottoming out the Watkins? I've not been able to do that with mine, but I'm sure it could happen.

- JP

Charivari said:

rstsgsas, there's just something right about seeing one of the bigger Quantum speakers getting all the juice they can take. Must really be something to hear when the music cuts loose.

Clifselina, that auction makes me rather angry. First, EMITs rarely go for that amount of cash, but that's nothing. The fact that some greedy powerseller took otherwise perfectly repairable, rare QLS-1s in good condition and parted them out piecemeal for the greatest cash inlay is outrageous. There's not too many of these TOTLs out there and to see this destruction ... :tears:

- JP

Click to expand...

Reminds me of the Taliban destroying the 1000 year old Budda carvings in Afghanistan.

Maybe I could offer to swap some Blose miracle cubes for his Quantums and put my Kappa 6's in the ....

Oh @#@^!!! I don't have a room without a system in it....

No problems as fuses.

I have a few extra mids that I have repaired.I have not had them act as fuses.It takes several tries to clean off what ever covers the tinsels to get solder to hold.Several times I thought I had one fixed and when driven hard the solder joint was not good and just came apart.I have gotten pretty good now ,last one I did has not let me down no matter how hard it was drive.I have 2 sets of Quantum 3s,and 1 set of the Quantum Jrs ,so all in all I have a total of six of the mids in use.Thats why I have several spares.They have all been repaired by me .That way I will never be without the sound of my babies.I do not know exactly how much power I am putting out from the brystons as the lights in the front are calibrated in dcbls .i know have had them all lighting up without any problems.It does have a clip light in the last bulb green/red but have never seen it come on.