Q: My buddy told me that if I go to a 50-watt guitar amp from a 100-watt amp, the volume will be half as loud. But someone else said they would be about the same. Who’s right?
A: All other things being equal (they rarely are), a 100-watt amp will be 3dB louder than a 50-watt amp. 3dB is a noticeable difference, but nowhere near half as loud.