I may add this Kapatid.Why amplifier power and speaker sensitivity isn't everything.Here's other factors influencing how much power you need.
The first is room size.The bigger the room,the more amplifier power you'll need.A rough guide suggest that increasing the room volume(cubic feet) by four times(4x) requires a doubling of amplifier power to achieve the same pressure level.
How acoustically reflective or absortive your listening room is will also affect how much amplifier you need.Finally, how loudly you play the music greatly affects how much amplifier power you need.Acoustic gigs require much less amplifier power than high playback levels rock music.
Here's my input.Placing the speaker in a room helps (the walls, ceiling, and floor reflect and reinforce the speaker's sound), adding about 4 dB to its output. For example, a speaker that has a measured sensitivity in an anechoic chamber of 91 dB SPL at 1 watt at 1 meter. But putting it in a room raises its sensitivity rating to 95 dB SPL at 1 watt, 1 meter. A 95-dB sound level happens to be "very loud," as most of us would subjectively describe it. And it is--from 3 feet (1 meter) in front of the speaker. But moving back twice as far, to 6 feet. Guess what happens? We instinctively know that sound gets weaker as the distance from the source is increased, but by how much? A formula called the "inverse square law" tells us that when the distance from the source is doubled, the sound pressure weakens by 6 dB.So at a 6-ft. distance, the speaker is now producing 89 dB. Doubling that distance again to 12 feet, a fairly common listening distance. The speaker now produces 83 dB, which isn't all that loud at all. And if you sat 24 feet away, a not uncommon distance in big rooms, the speaker would produce 77 dB SPL.
But what about in stereo issue? Here's another oddity of loudness and the decibel. When one speaker is producing a level of 90 dB, adding a second speaker playing at the same level only increases the overall loudness by 3 dB! (The loudness does not double!). So the two speakers in stereo produce a loudness level of 93 dB.
So adding a second loudspeaker will raise the loudness at 12 feet from 83 dB to 86 dB. And don't forget we're still using 1 watt of amplifier power output.Take your note on this.But how loud are real-life instruments, orchestras and rock bands? Now, while 86 dB SPL is "fairly loud," it's not nearly as loud as what you might hear from a good seat at an actual rock concert or from an orchestra or pianist in a concert hall. A solo grand piano can reach peak levels of 109 dB SPL, a full orchestra and chorus in a concert hall will measure 106 dB, and a rock group, 120 dB SPL. Now let's try and get our peak speaker sound levels to 96 dB, "twice as loud" as our 86-dB listening level. That isn't that difficult because right now we're only using 1 watt per channel to drive the loudspeaker to 86 dB. So we'll need ten times as much power, or 10 watts, to reach 96 dB.
But things begin to change, and rather dramatically. Pushing the loudspeaker to what we might experience from a solo grand piano, 109 dB. We're at 96 dB with 10 watts per channel. Let's go to 106 dB. So that requires 10 x 10, or 100 watts. Close, but not quite there yet. Just 3 dB more. Remember, we have to double the power for a 3-dB increase in sound level. So 100 watts becomes 200 watts.Oppps! if your power amp has only low power watts than required power maximum output,expect a more problem. And what about the rock concert? Lowering our expectations and aim for 119 dB. Going from 109 dB SPL, which needs 200 watts per channel, to 119 dB SPL (ear plugs required) is another 10-dB jump and--you do the math--that requires 10 x 200, or 2,000 watts per channel!
From all this you can see the huge power requirements inherent in reproducing real-life acoustic sound levels in average or big rooms.And if your speakers are less sensitive (and many are), then the power demands rise even more dramatically. Sizeable rooms and greater listening distances will also increase power demands tremendously.
And what many of us don't realize until we hear it, is that clean undistorted loud sound often does not sound that "loud".It's the distortion that makes it sound "loud" .To remove those distortions and increase dynamic headroom relates to even more power.You can never have too much power, and that big amplifiers rarely damage speakers. Little amplifiers driven into clipping burn out speakers.
Here's a tip.Remembering the inverse square law...every time you double your distance from a point of energy, the apparent intensity falls to 1/4. The "trick" is to position enough loudspeakers with wide dispersion to provide proper fill to the area of interest. In doing so, as you move away from one source of sound, with it's decreasing intensity, you'll be moving closer to another, with it's increasing intensity. Done right no "hot spot-cold spot", and you won't have to crank anything up to really high spls. Quality counts!Sorry mga kapatid,inde talaga ganoon kadali lang mag-setup.Goodluck parin!
Direk
