Looking for good stereo advice... [Archive] - Audio & Video Forums


View Full Version : Looking for good stereo advice...

11-29-2005, 04:44 PM
Hello all, new to the forums here...
So here's my story, my roommate has a pair of B&W CM2 loudspeakers. Recently, both of these speakers stopped working. First, one just stopped after ~3-4 years of fine performance. It did not blow, but just stopped outputting noise. Pretty odd... So I brought some other speakers from home and hooked them up and a few weeks later the other one does the same thing; it stops working. The B&W speakers have a power handling of 50-120 W and the other speakers that I brought have says 200 W on the cover. The B&W speaker was set up with one wire coming from the amp and another going into one of the 200 W speakers. Both have the same 8 ohm resistance as well as the amp having 8 ohms. The B&Ws are set up with an input and output channel, so they are made for this type of stuff. My first question is could the power of the 200 W speaker cause the B&W to short out? Or is something else really odd going on here? I'm skeptical because the first one went out on its own.
Now comes the next thing. He took the B&Ws to his stereo dealer and they said that the warranty didn't cover them because they "have been abused." Now this kid isn't too smart with electronics so I'm sure whatever explanation they gave him is not what he told me because quite frankly I don't trust his ability to relay a somewhat advanced bit of information or to fully understand what he was told. Regardless, the speakers cost $400 to repair them both. My question is do you guys think I could get better speakers for that price? He says the B&Ws were ~1000$ when he got them, but I'm skeptical that we can't get something better for the price that would be paid to fix them. I've read some reviews for B&W bookshelf speakers and they seem to be overpriced, and I must say that the pair he has don't produce the best sound at high volumes for their price.
We live in the type of house that likes loud music by the way, so booming sound and bass is what we are after in purchasing a new set of speakers. Any advice would be great! Thanks.

11-30-2005, 02:43 AM
It IS possible to blow speakers with an amp that is rated for less than they are advertised to handle.


By overdriving that poor, abused, overdriven amplifier into severe clipping, which is SERIOUS distortion which CAN destroy speakers, which are rated in CLEAN watts. It's like putting dirty gasoline in your car. It may run for a while but eventually it'll die.

Methinks you both should learn what distortion sounds like and then learn to turn it down when you hear it.

If loud is your main concern, consider Cerwin Vega! speakers. They MIGHT be a little more forgiving but physics is physics.

11-30-2005, 09:02 AM
So it is possible for the amp itself to cause the speakers to completely die not by pushing too much wattage or power into the speaker, but by other amp-related issues?

And how much distortion should I expect from this? Are we talking serious sound issues that would make listening totally unenjoyable or just a little bit of distortion and crackeling, albeit a noticeable bit ... the type of thing that a smart, attentive music listener would notice, but not necessarily a drunken idiot...

That's good to hear because while I myself have an ear for when the speakers are too loud for their own good, my roommates tended to not be able to this semester and I would frequently get worried when they would blast the amp at enormous levels when they were intoxicated...

I was also kind of thinking that they somehow just shorted out, perhaps our cheapo surge protecter or the outlet was causing some other issue.

11-30-2005, 09:09 AM
Hi, welcome to AR.

I believe you have nailed it. A normal listener should be able to hear that the music doesn't "sound right." A drunken idiot may just twist the knob all the way to the right. Louder is better right? Wrong!

When an amp begins to clip it can cause damage to a speaker even when the speaker could easily take more (clean) power.

You have to find a way to keep the drunks away from the volume knob.

11-30-2005, 12:08 PM
What amp are you using? It sounds like your roomies cooked the B&W's, speakers not known for being party speakers. What you need are high efficiency speakers that you can beat the life out of until you get your own place and can relegate them to the garage (the speakers, not the roomies ;)). Mark's suggestion of Cerwin Vega! fits the bill. You might also try Klipsch or JBL. Whatever you buy, tell your roomies that if they break it, they bought it.

11-30-2005, 01:56 PM
So it is possible for the amp itself to cause the speakers to completely die not by pushing too much wattage or power into the speaker, but by other amp-related issues?When you say "amp related issues", there is nothing "wrong" with the amp,. It's just unhappy at being forced to try to produce more power than it can deliver. It expresses it's dissatiafaction by sending heavily distorted signals to the speakers, which are NOT what they were designed to handle. These cause the voice coils to heat up to a much higher tempeature than they were designed for. ...and eventually the end result is silence in one or more drivers.

As far as what to listen for, well, that takes a little common sense. You know what the music SHOULD sound like, right? Well, at some point it will start sounding grainy, garbled or in other ways simply "not right". At that point something is complaining. It's either the amp or the speakers but it doesen't really matter which one. Somebody ain't happy and somebody could get hurt if the situation isn't remedied.

Now, at this point one should have the sense to know that something ain't Kosher and turn it down immediately.

Congratulations! You've just learned audio rule # i, albiet by first hand experience. "If it starts to sound bad, turn it down NOW!"

FWIW, audio rule #2 is "always power down all attached components when kerfutzing with interconnects or speaker wires.

By following these two rules you can save yourself a lot of $$ and heartache in this hobby.