Problem: speaker rattle

hunky · « **on:** 7 Dec 2004, 10:29 pm »

Hey, been enjoying my new 1801's as I break them in. But now one of them has a rattle - or static sound on the highs of the signal. I did switch speaker wires to make sure something upstream wasn't the problem.

I haven't opened it up and will do so when I get a bit of time - but thought maybe someone could give me a hint what to look for. Bad solder joint or something? Or bad part? It doesn't sound like it is coming from the tweeter - more likely the main speaker. I haven't cranked these speakers up very much (have a Jolida 302 amp) because my days of loud music are pretty much over.

If any more info is required let me know.. but maybe something will be apparent when I open it up.

cheers, H

jackman · « **Reply #1 on:** 7 Dec 2004, 10:44 pm »

Hi,
I'm probably the farthest thing you can find to an expert but I've had a few rattles in my day (some in my head and some in the various speakers I have owned). First thing I'd do is tighten up all the screws on the drivers and tighten up the screws on the binding posts in back of the speakers. THE most common rattle noise has come from loose binding posts. Those little metal jumpers between the bi-wire binding pots love to rattle if you don't have them tightened down.

Next, if that doesn't work, I'd take off the jumpers and only play the tweeters. Listen for the rattle. If you don't hear it, then switch to the woofers. This makes it a bit easier. If you still have a rattle, open the speaker up. You may have wires vibrating against the PVC port. This is another, albiet, less common culpret. Lastly, this may be rare but it happens, you may have something in your speakers rattling around like a screw or ball of solder. Also check the screws holding in the binding post assembly and make sure the port is glued in tight.

If it's not something loose (as described above), you may want to listen to the drivers to see if one is damaged. The drivers in the 1801's can take a lot of abuse, and if you haven't abused them, this not a very probably cause of arattle, but anything is possible. Listening to the woofer and tweeter independently (by plugging in two wires into the binding post with the jumpers disconnected) can help you determine what is causing the noise.

If this fails, I don't know what to say! 99% of the time I get a rattle, it's the binding post not being tightened enough and the metal jumper vibrating. That's my bet!

Keep us posted.

Jack

Al Garay · « **Reply #2 on:** 8 Dec 2004, 12:15 am »

Also, check for loose connections in your crossover. Are any exposed leads touching each other or the inductors? I used electric tape to coverup the inductor (Alphacore) leads.

Al

David Ellis · « **Reply #3 on:** 8 Dec 2004, 02:41 am »

Quote

static sound on the highs of the signal

The advice given above is good. I think Jack's hunch is probably the most accurate.

The most complex problem was done/found by Darren in Washington. He managed a cold solder joint via too much heat. After re-soldering the crossover the problem stopped. I recommend this persuit only AFTER all other problems are eliminated.

I recommend starting with the easy stuff, then working towards the crossover.

1. Yes, ensure you don't have any wires touching.

2. Yes, ensure your binding posts + are snug internally.

3. Yes, try isolating the sound to the tweeter or woofer circuit of the specific speaker.

Then:

4. After isolating the driver, swap the suspected bad driver with the good driver. Also, put the suspected bad driver in the good circuit. I always get dual-phenomenology when processing through an issue. Where is the noise? Follow the noise inward toward the crossover.

//

Also, the noise might be in your recordings or source gear. This has happened before with the 1801s. Try switching your speaker wires. Does the noise move?

Thanks for posting about this issue here. Thanks for trusting your ears on this issue too. As you progress through the issue, please feel free to post your struggle/progress. Your effort could indeed be very fruitful for others in the future.

hunky · « **Reply #4 on:** 8 Dec 2004, 05:08 am »

Many thanks for the help.

OK, I'm going in. I switched speaker wires and it is the one speaker. I disconnected the tweeter and the defect is still there (woofer). I'll take a quick look and switch woofers and see what happens. cheers, h

hunky · « **Reply #5 on:** 8 Dec 2004, 05:55 am »

Whoa! I switched woofers and now it is the other speaker - so it seems the woofer is the problem. I'll post a wav on my site and see if you can hear what I'm hearing. Not sure I will get it up right away.. cheers, h

fly_fish_nz · « **Reply #6 on:** 8 Dec 2004, 06:48 am »

H,

I had what sounds like the exact same symptoms with the Demo 1801's, occasional static from one speaker that sounded a little like rattling. Not too long later, the driver stopped working. The problem and fix were simple: by unscrewing the back plate I could see that one of the connectors/wire terminations from the cross over had worked its way loose. Fixed it up lickety split using a hemostat to reach in and reconnect it firmly to the connector to the speaker posts, and the 1801's were singing again.

Not sure what you meant by "switched woofers" and whether it rules out this problem, but if not you'll know if its the same issue with a quick look.

C

hunky · « **Reply #7 on:** 8 Dec 2004, 09:35 am »

I put the suspect woofer in the other speaker cabinet and it still is messed up. It is the woofer. I got a bad woofer or something. Tomorrow I'll take a closer look at it, but something is wrong. Sounds like I would think a blown speaker would sound like, though I've never heard one. I recorded it with a minidisc and then through analog into my computer and put it on my webpage so you can hear. The recording sounds more like a ringing.. it is a bit more static-y in real life.

speaker1.wav

David Ellis · « **Reply #8 on:** 9 Dec 2004, 12:30 am »

Great!

It looks like you are 90% down the right path.

You put the bad woofer in the good cabient, and the bad sound followed the woofer. This is great. It could be very easy.

Then put the good woofer in the "bad" cabinet. The sound should not be present.

After accomplishing this, please send me the bad unit. I'll replace it, and send you a check for postage... Dang, I QC these things with 25hz sine wave and break-in. Hmmmm, did your 1801 get a cryogenic treatment in your garage during a cold winter night

? Seriously, I really don't know what happened with that woofer.

I have only experienced one other woofer go bad AFTER mailing the 1801s to somewhere/someone. It was the tour 1801s. I really thought somebody cooked the voice coil via clipping or overpowering the unit. Maybe not. I sent this driver to SEAS for examination, but they never responded negatively. Hence, the cause wasn't abuse.

Your problem would support a .5 % future failure for the W18 driver. This bothers me. It'll require some thinking.

Anyhow, please to the dual phenomenology check by putting the good woofer in the bad cabinet. If this proves your situation, send me the bad woofer. I'll replace it.

Thanks again, and I am sorry you had to go through this.

hunky · « **Reply #9 on:** 9 Dec 2004, 01:47 am »

Yes, I had already swapped the woofers - the original speaker cabinet sounds fine with the good swapped woofer. I didn't want to run my amp with an unequal load (being on safe side) so I did that right away.

The weird thing is that it sounded fine the first week or two. I didn't notice the problem until I came home with a new tuner and hooked that up. Noticed the bad speaker then, and figuring it might be the tuner, I tried a cd of christmas music my mate had on (she hates any volume at all so I know she didn't have it cranked). I tried it with some of my fiddle music cds and rarely heard the problem - it seems worse on the higer registers of vocal and piano, but not screechy fiddle.

I am the sound guy for the community folk fest so I know somewhat how to handle electronic equipment - and I'm not one of those guys who likes it loud. My mate also knows sound equipment and I instructed her on how to turn on/off stuff. She always has the volume off when doing so.

I do have the speakers hooked up on the 8 ohm posts. I looked for info on that but didn't find any and assumed it wouldn't be 4 ohm.

So I don't know - maybe as you suggest it was a factory defect. I'll get it in the mail. -hunky

David Ellis · « **Reply #10 on:** 9 Dec 2004, 01:09 pm »

Good enough then.

I am slightly perplexed about why the woofer would go bad under normal use, but I suppose this is possible. I'll most likely send it to SEAS for examination. SEAS is very interested in this sort of issue. The last time I had a woofer go bad, John Stone, President SEAS USA, was tenacious about getting that bad woofer for testing.

Dave