How much power do your speakers need? | Crutchfield

You'll see all kinds of specs when you shop for speakers, but there's an easy way to determine just how much power they'll need from an amplifier to play at the right volume for your listening position.

The key to the calculation is the speaker's sensitivity rating, expressed by its measured decibel rating under one watt of power at a distance of one meter. Our expert walks you through how to calculate the power needs of your particular speaker at the distance from which you plan to listen to it.

[michealspangler]

this is the most helpful video regarding decibels to watts i've seen so far.

[davidgoodman]

I've been researching speakers and AVR's for my first surround sound set up. This video was the best at describing decibels to watts. But then again, anything Crutchfield is gonna be spot on. Thanks!

[jakobsloth]

This was the best explanation of this subject I've ever seen

[Zdk]

The formula is simply N+1. This assumes that N is the amount of Watts you currently have...

[drecartier]

This was so helpful. This whole time Im thinking my speakers are under powered because of how much my amp puts out versus how much rms my speakers can handle. I dont even need need a bigger receiver or add an amp.

[gk]

bravo guys, this helps a lot. You are the only one who could explain this simple thing so well. And this explains why the class D amplifier consume so little electric power!!!

[hifijunkie]

It’s all about headroom and the amps design. If you buy some 100 watt consumer market receiver, it probably has four 25 watt transistors and this is not capable of even using at it’s rated power. Not that you would need to listen to it at 100 watts but if you did it would sound like crap and be full of distortion and clipping. If you buy some high end amplifier it might have 36 output transistors and rates their amp at the same wattage you would be listening to it at the bottom end of its range which no clipping and no distortion.

So how many watts do you need for a full range floor standing speaker? At minimum you want to be at the manufacturers recommended wattage. But you would probably be better at double that.

[Romans_]

Very good explanation. The visual really helped. Thank you!

[B.B.Digital_Forest]

Thanks for this video. It confirms that I don't have to worry about how weak my choice of possible avrs could be. I prefer to listen below 80dB for the loudest sounds, i.e. explosions and rock music. So I'm sure my speakers will perform well enough at 2 meters distance.

[siriosstar]

excellent being a very visual person, that was the first time i have started to understand that topic . very well presented . lucid and concise .👍👍👍

[elephant]

this is the first time that I clearly understood driver sensitivity

[Arshar]

You explained about spl and wattage.. what about 1) spectrum and power distribution and 2) loudness

[MichaelCoffin]

Excellent explanation and examples. Very helpful. Thanks!

[rdfanrp]

This is an excellent explanation. Thank you!
However, there seems to be a mistake in the last example: It should have been 90db (not 87db) sensitivity for the first scenario (example at the bottom). That's the same example you had given in the previous segment while explaining the relationship between db output and power (90db sensitivity, 8 watts, 4 meters which translates to 87db output). Then it would match with the 2nd scenario (example at the top): 93db + 4 watts + 4 meters which is also 87db output.

[petermuwanula]

Brilliant explanation! 4 yrs later still best video. Everything is so confusing

[keepingupwiththejones]

Thanks for this explanation. I appreciate it.

[davidsicking]

Left out was important that the room be anechoic, lined with sound dampening material. The normal listening room csn vary widely, from draoes and carpet to hardwood floors. Classical music is very dynamic and in concert peak at 95-105 dB but have long passages doen at 40 dB quiet library. Duration is part of the damage to hearing. FYI.

[JoshWinter-ibsp]

Also a good idea to allow for dynamic range as well of at least 10dB. So yeah 8 watts gets the target, but ideally you want to time's that by 10 for burst power for dynamics so more like 80 watts really.

[scguy]

so it still begs the answer with your 87 sensative speakers what watt per channel in an AV rec do you need. ? I can figure the addition of the watts acccrding to distance and listening level but say you answer was 8 watts more needed ..to what baseline are we looking inthe AV - all AVrec will come at least a 30-50 watt perchannel

[muhammad_eid_ahmed]

One of the best information on internet 🔥