Determining exact power being sent to your speaker


How does one go about determining the exact amount of power being delivered by the amplifier to the speakers? Let's say the amp delivers 160w/channel at 4ohms (or so the reading materials state anyway) but yet the speaker specs show 120w maximum. My current integrated amp shows the volume
attenuation (dB units) in .5db steps ranging from -100 (min) up to 0.0 (max).

All that said, the concern is when should I be concerned about pushing too much power to the speakers and how I can determine the "Don't turn it up past this number on the display or you will damage the speakers..."
vineman55

Showing 3 responses by mlsstl

@stuartk -- seems you've also provided a good example of "prickly defensiveness"....  😉

The first thing I'd suggest you do is buy a sound level meter. Ones for home use are relatively inexpensive ($20 to $30) or you can download an app for your smartphone for even less, or free. This will give you a ballpark idea of just how loud you listen. (One's person's "loud" may be someone else's "medium", etc.) For example, my "loud" these days is around 85 dB average. 

Then, look up the sensitivity of your speakers. A lot of modern speakers have ratings in the upper 80s -- for example my Ohms are 88 dB -- it takes one watt of power to produce that sound level. Small bookshelf speakers tend to be a bit less sensitive, while many larger speakers, like horn systems, tend to be much more sensitive -- they will play much louder on that one watt of power. 

Even if one watt of power gives more volume than your average listening level, you still need more power than that from your amp. Music is dynamic with loud, short duration peaks above the average playback level-- such as a drum strike or orchestra crescendo. 

Unless you are a head-banger that likes your music at an average volume of 100 dB or more, there usually isn't much concern about having too much power, though some do get carried away on this issue. I happen to be in the camp that is more concerned about the sound quality of an amp rather than whether it has a zillion watts. 

@stuartk -- I have nothing against lots of power and have owned and heard lots of amps over the years, ranging from not much power to lots of watts.  So, you're putting words in my mouth with the "mutually exclusive" comment.  It's just in my case, my favorite amp is currently a 20 watt/channel class A Aegir, which replaced a VTV Hypex with many times the power. I prefer the Aegir's sound and never had a hint of running out of steam at my preferred listening levels. 

That's the nice thing about this hobby -- people can pursue what works for them. As they, YMMV for others.