"As a point of reference, my little Blackstar mini amp is a 3 watt amp and runs on 6 AA batteries, The Batteries last a pretty long time, The speaker is a 3 inch but not sure if it is 4 ohms or what. I suspect it is probably 4 ohms.
I bought the…"
"Wayfinder, to answer your question up above...you would use the Ohms rating of the speaker that you are using. But remember this does not mean that using a 4 ohm speaker is going to double the watts compared to using an 8 ohm speaker unless you have…"
"It's not that it won't work but it may not work to everyone's expectation. Loud enough for one person might be too soft for another. I'm sure this particular amp and speaker combo work fine or Gitty would be selling them. Not…"
"I think your math is a bit off, 250 Watts at 8 ohms is about 5.5 amps. Still the point you made is valid in that the power, spl, and volume are not linear.
Here is a link to an easy to understand write up on all this sort of stuff for those who want…"
"It is fascinating and almost counter intuitive.
On one hand, an amplifier pushing 2.5 watts to an 8 ohm speaker is squirting 0.5 amps down the wire, an amplifier pushing 250 watts to an 8 ohm speaker is squirting 50 amps down the wire.
"The watt rating of the speaker has nothing to do with the sound volume out of the speaker. What you need to look for is the sensitivity rating in SPL in db. Most home speakers are in the 87 to 89 db range. Car speakers are usually a little less. Pro…"