#1
Hey everyone thanks for taking the time to read this im sorry if some of my questions seem stupid but im kind a newbie to this whole PA amp speaker power watt thing. This is how i understand things to work if this is wrong please tell me ok so this is my set up at the minute i have two 500 watt speakers and a Behringer power mixer that can put 400 watts into each speaker ive been told this is a very dangerous thing to do as if the power amp is way lower than the speaker wattage clipping can occur and this can bust speakers which may explain the driver going in one of my speakers but that?s a different story, ok so anyways ive been told go get a new power amp that has a way bigger wattage than the speakers to avoid distortion and clipping is this right and if so can i use the Behringer mixer on bridge mode and combine both the 400 watts into one 800 watt signal and just run the speakers off each other it means id lose stereo control but that?s just life but the speakers would be safe is this true or have a been fed a load of ****e please help me thanks.
#3
ive been told thats a pile of crap and that its better to have a more pwerful mixer to stop clippin and distortion is this lies i got it from a pretty reliable source
#4
Yea, you want to have speakers with a higher rating than you can put into them.


Quote by Captain Face
ive been told thats a pile of crap and that its better to have a more pwerful mixer to stop clippin and distortion is this lies i got it from a pretty reliable source



Look you are wrong, whoever told you is wrong. Don't ask for advice and then say it is a pile of crap and your source is better. If your source is better then, ok then go keep blowing speakers. Think of it this way... if you have a track runner run a mile and a 400 lb man run a mile which do you think will do better? Sure the 400 pound man might be able to do it, but if he does it too many times he will probably die. You don't want to put more watts into a speaker than it is rated to handle. For ****s sake think about how stupid that sounds.
Last edited by myvaliantleap at Jun 1, 2006,
#5
my speakrs are at the minute but ive been told i blew a speaker becuas ei drove the power amo too hard and the power amps only capable of deliverin 400 watts and the speaker can take 500 so hows have a more powerful speaker stop this im not gettin at you or anything i just wanna understand all ths crap before i blow annother speaker
#6
You cant blow your speakers if your amp has lower wattage. The amp wont even make 450watts and the speakers can still handle 500Watts, so you know, no problem here... But another story is impedance, that can be a problem. But you wouldnt fry your speakers even if you used a 1000Watt amp with 500W speakers if you didnt turn the volume u too much. But that is very unsafe, sont do that. I had a 20W amp and a 15watt speaker and I was using it for a few months and it wasnt until I cranked the amp to full volume that the speaker blew (also did the amp :P)
#8
Quote by Captain Face
ive been told thats a pile of crap and that its better to have a more pwerful mixer to stop clippin and distortion is this lies i got it from a pretty reliable source


This is just untrue.
And next time use some periods
I'm not very active here on UG currently.
I'm a retired Supermod off to the greener pastures of the real world.
#9
It's simple, really.

The speakers are 500 Watt speakers.

They can handle up to 500 Watts.

If you put 800 Watts into them, they will blow up.

If you put 400 Watts into them, they will not be working at their most powerful, however, they will not blow up.

Clipping is mainly to do with solid state amps trying to work at or near their maximum voltage.
Posers are like punks, except they do it for fashion

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#10
Ok, your ohm setting has to be the same or else you will mess it up. You don't want to put more watts into the speaker than it can handle. You want it to be a little low. You can look it up on google if you need to know specifics but if you follow those two guidlines you will be ok.
#11
i donno i bew a speaker with a rating of 500 watts peak with a power amp that puts out 400 watts and the behringer site recomened speakers that are 200 watts with a 400 watt peak im still confused about this whole thing really
#13
nope theyre stage lines the ohm rating is fine i checked it the pa is sendin out a signal which can be between 4 and 8 ohms and the speakers are 8 ohms im usin stage line speakers with a peak of 500 watts what i dont underatnd is if behringer say use it with speakers with a peak of 4 hundred and i used speakers with a rating of 500 how the **** did they blow
#14
Ask the folks who sold you the speakers.

But your main concern was about clipping. Clipping has very little to do with the speaker, and much more to do with the preamp.
Posers are like punks, except they do it for fashion

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#15
hey i just seem somethin on a website that says contrary to popular belief your more likley to damage speakers by underpowering then than overpowering and that a speaker rated at 300 watts should have between 300 and 600 watt power amp so i blew my speaker becuase the power amp was a lower wattage than the speaker
#17
Quote by Captain Face
hey i just seem somethin on a website that says contrary to popular belief your more likley to damage speakers by underpowering then than overpowering and that a speaker rated at 300 watts should have between 300 and 600 watt power amp so i blew my speaker becuase the power amp was a lower wattage than the speaker


Link?

If you want to believe that, then go ahead, but don't ask for advice.
Posers are like punks, except they do it for fashion

notUG PUNK FORUM PRESIDENT!
#19
How much power do you need?
See the Power Amplifiers section of this buying guide. Fortunately, you can determine this without having to do (much) math. JBL recommends that, in general sound reinforcement situations, you use an amp that delivers equal to or up to double the IEC power rating of the loudspeaker, i.e., a speaker rated at 300 watts capacity needs a 300- to 600-watt amp. Contrary to popular belief, you're more likely to damage your speakers with an underpowered amp than with one that has too much power, so don't scrimp here!


However, they are trying to sell speakers.

Another website (http://www.clubknowledge.com/Car_Audio_FAQ/archives/1081.html) said this, although it mainly applies to car speakers:

First off, let's define CLIPPING distortion...

This is when an amplifier has reached its maximum output capacity yet tries to keep up with the input signal gain ratio between the signal source "HU" and Amp. The amp hits an imaginary wall whereby the output signal is no longer a symetrical replication of the input signal. The wave form in, does not match the wave form out in shape or amplitude. (you can see this easily if you had a A/B channel oscilloscope; channel A connected to the amp input, channel B to amp output) The only difference you should see between channel A & B are signal amplitude values. If the signal shape varies considerably in channel B, you have a problem with clipping.

So.. what's wrong with this picture? The amp tries to put out the appropriate power, but runs out of voltage from the supply rails and we get a flat spot at the upper and lower peaks of the wave form. In an extreme case, "severe clipping", there is so much additional energy buildup (heat) into the voice coil(s), but the cone does not move (motivate) enough to cool the voice coil and former adequately. Hense, the voice coil over heats and either seizes in the gap or burns the voice coil windings. RESULT: OPEN CIRCUIT and a blown speaker!

OK, what happens to the speakers when they are underpowered? Under normal listening conditions... NOTHING! There is adequate signal voltage from the amplifier to motivate the speaker. This moves the speaker cone and draws/expells air to cool the voice coil adequately. No problems here... just modest output from the speaker. This happens all the time when we ride with the tunes playing low enough to hear our buddy in the co-pilot seat chattering on his/her cell phone.

SO WE CAN USE LOW POWER SAFELY ON SPEAKERS?

Yes... When we use a small amp to drive a high powered speaker, the speaker can take all the "clean power" the amp can deliver and more. But it's when we push the amplifer into high distortion ("clipping") mode, the speaker cannot move (motivate) in and out adequately to cool the voice coil. Eventually, this will even fry a very expensive speaker in this manner.

WELL THEN WISE GUY... WHAT CAUSES THIS "CLIPPING" THING?

Glad you asked! The amp will try to meet the power demand placed upon it, but it cannot exceed its design capabilities. This in turn, produces the deadly "square wave" output to the speaker. The speaker sees this severely clipped signal as something similar to DC current. Speakers cannot deal well with DC inputs. The cone goes in or out and stays there. No motivation to cool the voilce coil and sooner or later, the speaker will fail.

YEAH... YEAH... SO WHAT CAN I DO TO PREVENT THIS?

Alright, we know what clipping is, how it affects amps and speakers. What do we do to keep this problem from destroying our expensive drivers? Easy deal:

1. Use amps that closely match or modestly exceed the power rating of the speaker. A 100 watt speaker will love getting 125 watts of "clean power" vs a 100 watt speaker getting 25 watts of badly clipped (distorted) power.

2. Know what distortion sounds like and prevent it by proper amp setup procedures. (HU/amp gain matching, limited bass boost usage)

3. If you are not sure your system is clipping, best thing to do is get out
of the vehicle, open the doors and step to the rear of the vehicle about 10 feet and listen...

a. Are the highs and mids clear and natural sounding or harsh, shrill and very poor SQ? You are clipping the amp if you hear the latter!

b. Does the bass sound full, tight, have a definite thump and smooth transitions from one note to another? If not, good chance the sub amp is clipping or your enclosure design is not optimal for the subs.

OK, that's about all I can do for now on this topic... Class dismissed and PLEASE... NO CLIPPING ALLOWED !!! 15 yard penalty and you will pay the piper eventually.

Swez HAPPY


I think it boils down to...

If your speakers are SEVERELY underpowered, they will overheat, because the voice coils won't be moving to cool themselves.
If your speakers are overpowered, it's obvious what happens.

And your best bet is to match up the voltages of your speaker as much as you can to your power amp.


If you'd rather follow what you've been told by your music teacher, then do that, and don't ask for advice here.
Posers are like punks, except they do it for fashion

notUG PUNK FORUM PRESIDENT!
#20
The thing about clipping and distortion is easy: If you have a lower wattage amp, and you push it, it'll clip/distort at a lower volume than a higher wattage amp would.
That's completely true.

However, if you're pushing a higher wattage through the same set of speakers, they'll blow.
If you have 2-400w speakers, then you'll be able to drive 800w.

I'm just sorry, I don't quite understand what you're saying, though, I don't know if what you're saying means anything.
Last edited by greenbox at Jun 2, 2006,
#21
^Well, a well designed PA system won't clip...they'll build in maximum level checkpoints.
greenbox is 100% correct too, I just wanted to add that in.
I'm not very active here on UG currently.
I'm a retired Supermod off to the greener pastures of the real world.
#22
i have a quick question on this topic. If i have a 4ohm line out from a combo amp(75w)with max watt of 100w written next to the line out, and i have a cab rated at 120w, will this be a reasonaly suited match. is it likely to fry anything?
#23
^Should be fine.
I'm not very active here on UG currently.
I'm a retired Supermod off to the greener pastures of the real world.
#24
thanks. THink i have most of the info i need now. time stop talkin and get started>