Distortion

[u_dakka]

Our speakers at school have started to distort quite badly - to those that actually listen in assembly anyway! It started about a week ago and has steadly got worse on one speaker. What are the Main reasons why distortion could occur in the system and what remedies could u suggest?
cheers
andy

[Roger]

One of 2 things cause this...
1. sending to much power through the speakers makes the driver over extend itself and crackle or make other funny noises its not supposed to. This can damge the speaker rather quickly. If this only happens sporadicaly (during periods of high volume) just turn your amplifiers down or adjust the settings on your comp/limiter (if youve got one)

2. If it does it all or most of the time one of the drivers is more than likely blown. If you are one of the lucky ones that have a frequency generator use it to determine if youve blown a tweeter or woofer. If you dont have one you can play a cd through the speakers and use the eq on the board to isolate certain frequencies.
-Roger

[RelativeMischief]

Originally Posted by Roger

2. If it does it all or most of the time one of the drivers is more than likely blown. If you are one of the lucky ones that have a frequency generator use it to determine if youve blown a tweeter or woofer. If you dont have one you can play a cd through the speakers and use the eq on the board to isolate certain frequencies.
-Roger

I'd just shove my ear right next to the driver I want to listen to. But I work with portable gear, not flown install so your's is probably the better suggestion

If your driver is blown check the warranty info, you might be able to write it off as wear and tear and get a new driver and the fix done for free. I know there's one company (of course I completely forget which one right now) who have a lifetime "we don't care how or what happened, we'll fix it for free" warranty policy. All I remember is that their stuff wasn't that great so the fixed alot of it :P Something to be said for public relations though.

Another thing you can check is your connections. A dirty enough connection (especially RCA I've found) will really start to sound like bad distortion. This goes as well with loose connections, same kinda sound (both times signal is being interrupted so they both sound like the same problem).

[freshmantech]

distortion could be caused by several other things than listed above.

do you have a mixer (sound board) and if so have you checked the gain - if gain's too high you can peak a signal and cause massive distortion...similar to many punk recording sounds.

as mentioned in the other replies - the driver could be blown and you could use a freq. generator to figure that out with more precision. you can download a free copy of adobe audition (30 day trial)...it's one of the "greats" for audio mastering and has a tab to insert a frequency...basically a freq. generator. It's about a 150 meg DL though from the Adobe site (adobe.com) but from a school's "fast" internet that shouldn't be a problem...also a nice software for post editing if you don't use ProTools / digidesign

You could have a peaking amp - as suggested above - just turn it down.

and finally - you could just have a crappy mic and crappy person speaking in the assembly...this is probably the case (as with most speakers...the people not the device...so do what most of us do...ignore them and use the "good" stuff for a nice rock concert, musical, etc.

Good Luck!

[cutlunch]

Originally Posted by u_dakka

Our speakers at school have started to distort quite badly - to those that actually listen in assembly anyway! It started about a week ago and has steadly got worse on one speaker. What are the Main reasons why distortion could occur in the system and what remedies could u suggest?
cheers
andy

Hi. Every thing that is said has been good advice. There is one thing I would like to know, are your speakers wired in a mono or stereo configuration?

If they are in a stereo configuration that makes testing easier. If stereo just swap the leads from out the back of the amplifier and if the good speaker now distorts then it is in the signal path for that channel back from the amplifier to the mixer. If there is no change then as the other people have said it is most likely the driver.

If you think it is the driver and you are allowed to, take the speaker down and if you can, open it up and check that the leads haven't come off somewhere. Also visually inspect the crossover to see a capacitor hasn't died or a track lifted etc.

In a mono wired system it is more likely to be the driver if one speaker is good and the other is bad. Check again for loose leads etc.

[Andy_Leviss]

Also, somebody here posted that amps can damage speakers by giving them too much power. While this is true, I feel obligated to point out that far more damage is done by using underpowered amps than overpowered. I'll leave you to do a bit of research elsewhere online for a good explanation, because at 11:30p with a 7a call for a load-in, I'm not exactly up to trying to explain it lucidly right now ;o)

[VipermanGTX]

all the Info provided above, i agree with. you should realy try everything we think mite be wrong. Trouble shooting can be the greatest way to learn and the hardest..... its also fun.... once you get to a point in your audio life.....you think its fun......you just wait an see.