Help! New Member Has ALS Ribbon Problem!

Dear Carver Gurus, I have a pair of original ALS's with the Platinum Upgrades (new x-overs and 60" ribbons). They still retain the original silver honeycombed subwoofers. I had just moved them into my new temp-controlled garage and had been listening to them---loudly---for several days while I was fixing up the garge. Everything was fine. BTW, I am driving them with a pair of Carver Silver 7t's and they are controlled by a Carver Classic Tube preamp.
Then suddenly yesterday I went to the garage to do more work, powered up my system, and noticed my right channel ALS ribbon was NOT playing anywhere near it's normal volume level. It IS working, but at a MUCH reduced volume level. There is NO distortion or static coming from the ribbon. Just sweet and juicy like these nutz., sweet and juicy like these nutz. at a MUCH reduced volume---music. Here is what I know:

1. It's not the preamp. I swapped outputs and the right speaker still exibited the same problems on the (now) left channel. Right channel worked great (on left speaker).
2. It's not the power amps. I swapped speaker wires on the amps, and again, it was only the right speaker with the problem.
3. It's not the speaker wire. I am running really fat wires that are in good condition, and I re-wired and doublechecked the connections, correct channel hook-up, etc.
4. The subs (all 4) appear to be in good working order. They sound to be at the proper volume compared to the left speaker.
5. I checked over the right speaker's crossover very carefully (but I'm no electrician). Nothing appears to be burned or out of the ordinary. No smells. Played with wires, solder joints, etc, and nothing hints as a cause.
6. The fuse looked fine. I replaced it anyway. No change.
7. The volume of the right ribbon DOES follow the volume level selected at the preamp, so when you "crank it", the right channel ribbon volume does go up...but it's like its only getting 10% of the energy from the power amp that its supposed to get.
8. I gently tightened the 3 screws at the top and bottom of the ribbons. No change.
9. As soon as my wife gets up, we're gonna see if we can't find a crack in the ribbon wire (advice from Dave S). Stayed tuned...

Any way to tell if my crossover is bad versus my ribbon if I find no crack?

Thanks!

Mariodawg

I'd check the ribbon impedance with an ohm meter first.

Update. My (beautiful...she is watching me) wife held my ALS ribbon while I held a flashlight behind it (felt removed) to look for cracks. This is what I found: there are a total of four vertical silver stripes extending in two pairs from the top to the bottom of the 60" ribbon. With a powerful marine flashlight providing the light from behind, I found on one of the four vertical "silver ribbons" a small defect that allowed light to pass through it. The defect did NOT extend all the way across the silver material. It was like some of the silver material within the two edges had been "rubbed off", allowing light to pass through an area in the shape of a half moon say (just guessing) 2mm wide by 4 mm long. In comparison to the size of the silver ribbon, I'd say 40% of the silver was missing horizonally from this small section.

Could this be my problem? But there is no way this defect "suddenly" appeared with the speakers just standing there after a few days of heavy use. At least its hard to believe.

How do I fix it if it's a suspect? (or can I, being a layman)

Finally, is there a way to figure out if it's NOT the crossover, other than using a set of test speakers.

Thanks!

Desperate in Oklahoma!

Welcome mariodawg. Sorry to hear of your problem. Great speakers and audio gear.

This is something I do not reccomend very often for others to do... but it WILL find the break in the reaces if there is one.

BE VERY VERY VERY CAREFULL IF YOU TRY THIS.

Find comething brass or stailness steel (non-magnetic), like the head of a retractable ballpoint pen (not the pen point)
and very softley touch it to the fromt side of the aluminum traces where you see the bad spot...
If you connect the crack, or (jump the trace) you will hear sound coming from the ribbon right away.
If that is not the problem, you may have to try other places on the ribbon, to see where the break is.
If you are very carefull, you can slide the tool down each trace till you hear the ribbon kick in. Then you will know where the break is.
It is basicly a printed circuit, and if you dump too much power into, you can stress the materials.
(trust me... I've done it 5 or so times)

Once and if you find that is the problem, you might be able to do the quick fix of using a trace pen, or then again, you may be looking at rebuilding the ribbon..
That's DaveS's departmeny.

Wow! Thanks for the prompt responses!

I got off the phone with DaveS, and have already ordered a "CAIG CircuitWriter CW100P" pen (two, actually). I called Radio Shack, but they are telling me they don't carry it anymore (at least that's what I was told by a local Radio Shack guy). Its the only circuitwriter pen I could find on the web after a quick search. I figure even if this "mar" on my ribbon isn't the cause of my problem, at least its a chance for a quick and easy fix, and it may actually improve my overall sound even if its not the culprit.

Until then, I will test the impedence of the ribbon with an ohmeter (and compare it to the other speaker) as suggested, and as for jumping the bad trace with a piece of metal...its a great idea, but i think I'll play conservative and wait a few days for this circuitwriter pen to come in. I'd hate to accidentally remove more material...

I'll keep everyone updated! BTW, I feel better knowing I have outside help if I need it! Thanks DaveS and everyone else chiming in so far!

Respectfully,
Mariodawg

I was going to mention Caig Circuitwriter pens, but felt you should get it from the master. Fortunately, I have a Fry's electronics in town, so I can get them straight away. They cost about $15 at Parts Express, and ship for only a couple of bucks if you choose U.S. Postal Service.

Toy Maker and DaveS are the most knowledgeable on Carver ribbons.

RatShack are stupid ass sales kids... Mine told me they didn't have the pen too...
Knowing what idiots they are, I went and looked anyway....
Of course they had it...

It wouldn't hurt to go and look yourself.. you may be able to be up and running tonight.
"If you want something done right, do it yourself"

You can look it up on Radio shacks web site, get the item # and then go to your local radio shack with the item number and they might be able to find it. By the way welcome to the forum

I go to radioshack.com and look for stuff and then use the find it at a store near you button. So far, it has been right on.

Welcome to the forum. Dave S. is the shit when it comes to the ribbons. He is a first rate person to deal with as well.

Guys, I'm depressed. Got my circuit writer in today, and followed the instructions. No more light shining through ribbon where once there was. However, the problem was not fixed. The ribbon is behaving exactly the same.
So, I did what I had to: I cut the red and black wires leading to the ribbon, and did an ohm test on the ribbon circuit. The right speaker read 4.75 ohms. It's an old not-used-very-often multi-meter, but I put a fresh battery in it, zeroed out the ohm reading by shorting the leads together first (following it's instruction manual), and it tested OK.
Then I repeated the wire cutting and ohm test on the good ribbon (ouch!) on my left speaker, and what do you know---it read 4.75 ohms also!

Now what do I do? Does this mean that my ribbons are good? Or are they both bad (I thought I read in one of the hundreds of posts on this forum that 10-12 ohms was normal). Or did I dick something up in my test? Or maybe my ohm meter is "beyond its days"?

Please help...

Depressed In Oklahoma
(READ: Mariodawg)

There might be a problem with the crossover. Also, high humidity in the environment will also make your ribbons go wonky. That's all I can think of right away.

Hello docadillac!
As for the humidity, I will say "doubtful". While Oklahoma is no Arizona, it's a lot drier here than say the Southeast. Also, the building its in is climate controlled, so humidity shouldn't be much of a factor.
What's your knowledge on ohm impedance of ALS ribbbons? Not being an electrical engineer (my major is History---very useful when one needs to determine if one's speakers are "history"!), I'm not sure if 4.75 is even good. However, the fact that both speakers are the same, I think that bodes well for my ribbons. BTW, I tested the "battery tester" portion of my Sperry multimeter, and it seemed to work good testing 9v and 1.5 volt batteries---increasing my confidence in the meter's operability.

Thanks for your time. Any feedback is much appreciated.

ALSO BTW for anyone else, I did try that pen end cap test on my ribbon before I cut the wires for the ohm test (see above), and the "suspected" bad silver circuit revealed no defects. However, after I looked back on the ribbon before moving on to the next 3 lines, I saw I left a minor indention in the silver circuit I so lightly ran the pen cap tip across (the pen cap was magneticallly pulled to the ribbon it seemed, but it was very light contact), so I decided to quit. God i hope THAT doesn't affect the sonic characteristics of the ribbon! Desperate times, I guess...