Clipping? Is this it?

[Rolyasm]

Hello all,
I was just over at my friends house and he has an amp that specs at 300wx5. We were running some speakers, some old Polks, and the lights on his amp came on when we approached high volumes (-10 on his Denon). He told me that the system was clipping. I always thought clipping was when the amp wasn't up the task at hand, but 300w into Polks seems like ample power. What is up? Is the amp really causing the problem, or is it something else. Thanks.
Roly

[Glen B]

Volume control position bears no relevance to output level and clipping. The type of listening material, room size, efficiency/sensitivity of the speakers and how conservatively the amp is rated all determine how soon its limits are reached. Exactly what amp is this ?

[Rolyasm]

It is an earthquake amp. So my question is, when the lights are coming on, on the amp, is it clipping, or something else. And does this mean the amp is running out of juice for the speakers, or vice versa?

[Glen B]

It is an earthquake amp. So my question is, when the lights are coming on, on the amp, is it clipping, or something else. And does this mean the amp is running out of juice for the speakers, or vice versa?

I am not familiar with the specific features of the Earthquake amps but regarding amplifiers in general, the purpose of clipping lights is usually to indicate the ONSET of clipping. If clipping lights on the Earthquake amp are coming on then they're saying that the amp is clipping or about to clip, depending on the point at which the manufacturer has designed them to light up. Every amp has its limits. Even a 300W x 5 amp will eventually run out of power when pushed hard enough. It can take a lot more power than you might think to reproduce some musical material at realistic levels, especially if the speakers in use are not very sensitive.

[peterS]

www.bcae1.com explains clipping quite well

go to #84 (cant link dirrectly)

[Clive]

You'll have to read the specs properly just to be sure that all channels are driven. The 300 x 5 may be 300 watts divided by 5.

Checks the true specs. Check the ohm load on those speakers too!

[peterS]

You'll have to read the specs properly just to be sure that all channels are driven. The 300 x 5 may be 300 watts divided by 5.

Checks the true specs. Check the ohm load on those speakers too!

impedence doesnt affect clipping... but then again i wouldnt be relying on some led lights

[Rolyasm]

The amp is rated very well. I think it is 320 watts, and I know it is all channels driven. Rated down to 2 ohms at 750 watts, all channels. So Peter, you said you wouldn't rely on some led lights. There is no sound difference when the lights come on. I checked the link above and I didn't see the subject of Clipping covered. Anyway, what does clipping sound like? Doesn't the speaker just start to cut out? At that point has damage necessarily been done already, or if you turn it down quick, is it safe. It would be nice to push the speakers close to their limits, but not over. Is there such a magical place? If there were no LED lights, we would have thought nothing of going louder. So how can I procede, but still be safe? Here is a web site review if you want to read the specs.

http://www.hometheatermag.com/poweramplifiers/905earthquake/index2.html

Roly

[peterS]

The amp is rated very well. I think it is 320 watts, and I know it is all channels driven. Rated down to 2 ohms at 750 watts, all channels. So Peter, you said you wouldn't rely on some led lights. There is no sound difference when the lights come on. I checked the link above and I didn't see the subject of Clipping covered. Anyway, what does clipping sound like? Doesn't the speaker just start to cut out? At that point has damage necessarily been done already, or if you turn it down quick, is it safe. It would be nice to push the speakers close to their limits, but not over. Is there such a magical place? If there were no LED lights, we would have thought nothing of going louder. So how can I procede, but still be safe? Here is a web site review if you want to read the specs.

http://www.hometheatermag.com/poweramplifiers/905earthquake/index2.html

Roly

the only way to know for sure is with an oscelloscope
click on the link and scrole down to #84
it is titled active vs passive
clipping is clearly discribed within

they say you can clip by over 9db before you hear it (in sub frequencies at least), making the ear a bad measuring device for it

on passive x/o networks the tweeters will take the brunt of it (as explained in the link)

with a sub woofer you will be sending up to twice the power while the driver doesnt move along its full motion, resulting in less cooling

under the right conditions you can blow a speaker in seconds by clipping, not to mention the amp, since it is being over driven also