overpower and underpowering components speakers
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overpower and underpowering components speakers Car audio NooB questions...
Can I blow a set of component speakers that draw 120W rms at 4 ohm with an amp that puts out 150W rms at 4 ohm?
What effect would an amp that puts out 75W at 4 ohm have on the same 120W rms 4 ohm speakers?
I'm having a tough time finding a brand matching amp to power the components I want.
Can I blow a set of component speakers that draw 120W rms at 4 ohm with an amp that puts out 150W rms at 4 ohm?
What effect would an amp that puts out 75W at 4 ohm have on the same 120W rms 4 ohm speakers?
I'm having a tough time finding a brand matching amp to power the components I want.
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Well you'll get 100 different answers on this one, but here goes. The only thing that will smoke a speaker faster is distorion. rms ratings are there so you have reference point to go from and its what the companies give to you becuase thats usually the highest power they have tested them at without blowing them + playing all kinds of tones thrue them. So withall that in mind as long as you have a great headunit and great amp you shouldnt have any problems, but you should never go above factory rms ratings.
Originally Posted by silvrbreez02
Car audio NooB questions...
Can I blow a set of component speakers that draw 120W rms at 4 ohm with an amp that puts out 150W rms at 4 ohm?
What effect would an amp that puts out 75W at 4 ohm have on the same 120W rms 4 ohm speakers?
I'm having a tough time finding a brand matching amp to power the components I want.
Can I blow a set of component speakers that draw 120W rms at 4 ohm with an amp that puts out 150W rms at 4 ohm?
What effect would an amp that puts out 75W at 4 ohm have on the same 120W rms 4 ohm speakers?
I'm having a tough time finding a brand matching amp to power the components I want.
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Rep Power: 0 I'm in a good mood, so I'll give you a good answer. First you need to know the basics of what is going on.
Speakers use power to produce sound. The more power you feed them, the louder they will get. No power = no sound. The rms rating is for continuous power, or how much power you CAN feed them all day long w/o damaging them. The max rating is how much power the speakers can take in short bursts.
Amps put out power. The rms rating is for continuous power, or how much power the amp CAN put out all day long w/o overheating. The max rating is how much power the amp can output in small bursts.
With that said these numbers are just approximations. They allow you to have an idea of what a speaker or amp is capable of. In theory for every double in power output the speakers can get 3db louder. So ideally the only difference from a 75 watt amp to a 150 watt amp is about 5db total volume potential (150 watts vs 240 watts).
If the speakers are 120 rms .... any amp in the 40-150 rms range should work. The more power, the more potential volume you can have.
Also, don't buy into this underpowering crap. If speakers died from underpowering they would all blow the minute you turned the volume down from anything but max. What blows speakers is distortion and clipping. This happens when people are too dumb to turn down the volume when a speaker and amp are giving out. .... I don't want to generalize, but the people who are blowing speakers from using amps with less than the recommended power generally don't have the amps gain set correctly, insist on using the bass boost and loud features, and don't know enough to turn it down as its crapping out.
Speakers use power to produce sound. The more power you feed them, the louder they will get. No power = no sound. The rms rating is for continuous power, or how much power you CAN feed them all day long w/o damaging them. The max rating is how much power the speakers can take in short bursts.
Amps put out power. The rms rating is for continuous power, or how much power the amp CAN put out all day long w/o overheating. The max rating is how much power the amp can output in small bursts.
With that said these numbers are just approximations. They allow you to have an idea of what a speaker or amp is capable of. In theory for every double in power output the speakers can get 3db louder. So ideally the only difference from a 75 watt amp to a 150 watt amp is about 5db total volume potential (150 watts vs 240 watts).
If the speakers are 120 rms .... any amp in the 40-150 rms range should work. The more power, the more potential volume you can have.
Also, don't buy into this underpowering crap. If speakers died from underpowering they would all blow the minute you turned the volume down from anything but max. What blows speakers is distortion and clipping. This happens when people are too dumb to turn down the volume when a speaker and amp are giving out. .... I don't want to generalize, but the people who are blowing speakers from using amps with less than the recommended power generally don't have the amps gain set correctly, insist on using the bass boost and loud features, and don't know enough to turn it down as its crapping out.
basically, for best performance and to get what the speakers are meant for, just match the rms watts and ohm impedance from the amp, to the rms watts and ohms impedance from the speakers. keeps it simple and sounding the way the manufacturer intended for it to sound.
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^^^ Valiant advice but nearly impossible.
You really aren't going to look up specs and see an amp listed as
4x150@4ohms rms, peak 200@4ohm, then see a pair of components that say, 150w rms, peak 200w, 4ohm. Life just aint that perfect. When you read the specs of an amp it's going to list all different possible combos of power and impedence. I'd say the most important thing to know is how to use your volume and gains. Like mentioned above, you can feed 150w components with only 70w amp. You might have to turn the gains up a little to provide adequate power and your sound may not be all that clear and crisp. Conversely, you could take a 250watt rms amp and power a set of 150w speakers beautifully. You just can't crank the gains and volumes. This is the better situation, albeit more dangerous - but only if you aren't smart about it. It's better to get an amp more powerful than your speakers for several reasons. 1. in the future, you may decide you want better speakers. You won't have to upgrade the amp, the power is right there waiting for you. 2. Like Ed said, more power allows you to keep the gains low. You are way more likely to blow your speakers with distortion by underpowering your speakers and then cranking up the gains and volume to make up for the lack o clean power.
You really aren't going to look up specs and see an amp listed as
4x150@4ohms rms, peak 200@4ohm, then see a pair of components that say, 150w rms, peak 200w, 4ohm. Life just aint that perfect. When you read the specs of an amp it's going to list all different possible combos of power and impedence. I'd say the most important thing to know is how to use your volume and gains. Like mentioned above, you can feed 150w components with only 70w amp. You might have to turn the gains up a little to provide adequate power and your sound may not be all that clear and crisp. Conversely, you could take a 250watt rms amp and power a set of 150w speakers beautifully. You just can't crank the gains and volumes. This is the better situation, albeit more dangerous - but only if you aren't smart about it. It's better to get an amp more powerful than your speakers for several reasons. 1. in the future, you may decide you want better speakers. You won't have to upgrade the amp, the power is right there waiting for you. 2. Like Ed said, more power allows you to keep the gains low. You are way more likely to blow your speakers with distortion by underpowering your speakers and then cranking up the gains and volume to make up for the lack o clean power.
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Originally Posted by Regularjoe
With that said these numbers are just approximations. They allow you to have an idea of what a speaker or amp is capable of. In theory for every double in power output the speakers can get 3db louder. So ideally the only difference from a 75 watt amp to a 150 watt amp is about 5db total volume potential (150 watts vs 240 watts).
If the speakers are 120 rms .... any amp in the 40-150 rms range should work. The more power, the more potential volume you can have.
If the speakers are 120 rms .... any amp in the 40-150 rms range should work. The more power, the more potential volume you can have.
I've done some minor installs myself in the past (single amp & two subs kind of stuff), but I've never gotten into the running everything in the car + subs off of multiple amps.
Anyway, thanks for the help.
P.S.-I'm looking into going with Alphasonik all around....any comments?
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Originally Posted by J187
^^^ Valiant advice but nearly impossible.
You really aren't going to look up specs and see an amp listed as
4x150@4ohms rms, peak 200@4ohm, then see a pair of components that say, 150w rms, peak 200w, 4ohm. Life just aint that perfect. When you read the specs of an amp it's going to list all different possible combos of power and impedence. I'd say the most important thing to know is how to use your volume and gains. Like mentioned above, you can feed 150w components with only 70w amp. You might have to turn the gains up a little to provide adequate power and your sound may not be all that clear and crisp. Conversely, you could take a 250watt rms amp and power a set of 150w speakers beautifully. You just can't crank the gains and volumes. This is the better situation, albeit more dangerous - but only if you aren't smart about it. It's better to get an amp more powerful than your speakers for several reasons. 1. in the future, you may decide you want better speakers. You won't have to upgrade the amp, the power is right there waiting for you. 2. Like Ed said, more power allows you to keep the gains low. You are way more likely to blow your speakers with distortion by underpowering your speakers and then cranking up the gains and volume to make up for the lack o clean power.
You really aren't going to look up specs and see an amp listed as
4x150@4ohms rms, peak 200@4ohm, then see a pair of components that say, 150w rms, peak 200w, 4ohm. Life just aint that perfect. When you read the specs of an amp it's going to list all different possible combos of power and impedence. I'd say the most important thing to know is how to use your volume and gains. Like mentioned above, you can feed 150w components with only 70w amp. You might have to turn the gains up a little to provide adequate power and your sound may not be all that clear and crisp. Conversely, you could take a 250watt rms amp and power a set of 150w speakers beautifully. You just can't crank the gains and volumes. This is the better situation, albeit more dangerous - but only if you aren't smart about it. It's better to get an amp more powerful than your speakers for several reasons. 1. in the future, you may decide you want better speakers. You won't have to upgrade the amp, the power is right there waiting for you. 2. Like Ed said, more power allows you to keep the gains low. You are way more likely to blow your speakers with distortion by underpowering your speakers and then cranking up the gains and volume to make up for the lack o clean power.
Originally Posted by Regularjoe
Also, don't buy into this underpowering crap. If speakers died from underpowering they would all blow the minute you turned the volume down from anything but max. What blows speakers is distortion and clipping. This happens when people are too dumb to turn down the volume when a speaker and amp are giving out. .... I don't want to generalize, but the people who are blowing speakers from using amps with less than the recommended power generally don't have the amps gain set correctly, insist on using the bass boost and loud features, and don't know enough to turn it down as its crapping out.
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