If a speaker has an SPL of 100dB with 1 watt at 1 meter, what would the SPL be with the same speaker at 1/10th of a watt at 1 meter?
More specifically, if amp A has a built in attenuator that reads as down to -35dB reduction on its dial, and amp B has a built in attenuator that reads as reduced watts down to 1/10th of a watt on its dial, which amp will have the most volume reduction at full attenuation if all else is equal, as in the first sentence above?
Thanks.
SPL technical Question
05/03/2020 1:50pm
2x the power = 3dB acoustic power increase. So...do the maths ;-)
Thanks Narco for your comment. To the best of my ability, I come up with -18dB. That being said, I'll re-state my question. All I'm trying to do is buy a new amp that fits my specific needs. I'm an older retired guy. Don't want to drop a large amount of $$$ on the wrong amp. Would very much appreciate any comments that are constructive and helpful.
So here is the question... if amp A has a built in attenuator that reads as down to -35dB reduction on its dial, and amp B has a built in attenuator that reads as reduced watts down to 1/10th of a watt on its dial, which amp will have the most volume reduction at full attenuation if all else is equal?
Thanks all.
Going from say 100W to 10W is 1/10th the power. There's a 3dB acoustic level loss when reducing the power by 1/2. 100/2 = 50/2 = 25/2 = 12.5-2.5 = 10. 3 (x/2) at -3dB each = -9dB. That last 20% power reduction is another -1dB. 1/10th power = -10dB. -10dB is generally considered 1/2 the acoustic level, but some say -6dB is 1/2.