Some guidance on speaker power and distortion...

[tentaguasu]

Thanks to all of you for some excellent comments and help in my ongoing quest to build a home theater on the cheap!

I'm still not completely clear on one issue - when I turn up my stereo too loudly and it starts to sound really bad, what is failing, my speakers or my receiver or both?

I always assumed that it was excessive power coming out of the receiver that the speakers couldn't handle and that bigger speakers would solve the problem.

This is why I was concerned when I was tentatively considering going with 2 bookshelf DIY speakers (maybe the madisound recession buster) paired with a subwoofer for my 15x18 ft theater room. I thought they would be too small to fill the room but several people have assured me that with the properly powered receiver that should not be a problem.

As a audiophyte, I've always assumed that speaker size roughly equates to speaker power, but now I'm questioning that assumption. I'm sure it does to some extent, but in my scenario is the receiver the "weaker link" in the system, such that I need to properly account for by carefully figuring out how many watts per channel I need to power the recession busters to the sufficient loudness?

 

[TLS Guy]

Thanks to all of you for some excellent comments and help in my ongoing quest to build a home theater on the cheap!

I'm still not completely clear on one issue - when I turn up my stereo too loudly and it starts to sound really bad, what is failing, my speakers or my receiver or both?

I always assumed that it was excessive power coming out of the receiver that the speakers couldn't handle and that bigger speakers would solve the problem.

This is why I was concerned when I was tentatively considering going with 2 bookshelf DIY speakers (maybe the madisound recession buster) paired with a subwoofer for my 15x18 ft theater room. I thought they would be too small to fill the room but several people have assured me that with the properly powered receiver that should not be a problem.

As a audiophyte, I've always assumed that speaker size roughly equates to speaker power, but now I'm questioning that assumption. I'm sure it does to some extent, but in my scenario is the receiver the "weaker link" in the system, such that I need to properly account for by carefully figuring out how many watts per channel I need to power the recession busters to the sufficient loudness?

It is impossible to say whether it is the speakers, the receiver or both running out of gas. Domestic equipment has to be played at sane levels. Generally smaller speakers are less sensitive than larger ones and require more power for the same spl. At the same time the smaller drive units of small speakers are generally less able to handle greater power without distortion, thermal compression and damage.

There are some exceptions, with small speakers from Dynaudio, SEAS and Morel, for instance, that have very large motor systems on small drivers. The drivers in the recession busters are not in that company, so they will have to be played at a sane level.

Any speaker that is going to provide fidelity, low distortion and high spl. is going to be an expensive item. However a high price tag does not guarantee that.

Unfortunately there are still far more bad speakers than good ones at all price ranges.

 

[j_garcia]

The sensitivity of the speaker has everything to do with how much SPL you can get out of it with a given amount of power. A speaker in the low 80s will require much more power than a speaker in the low 90s to fill a given room. In a smaller room, that becomes less of an issue because you don't need as much SPL to fill it.

Generally when you crank it up and actually hear distortion (fuzzy or crackly sound) that is the amp/receiver creating the distortion. The speaker itself not being able to handle the power is less likely, but also possible. If it only happens when you push the recever too hard, then the receiver/amp is underpowered for the SPL you are trying to achieve.