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Comment by IsTom | Hacker News Reader

You could have log Watts or something, it doesn't have to be dB to be logarithmic.

We have a unit for that. It's dBm and very easy to grasp. 0 dBm is 1 mW, every 10 dBm is an order of magnitude more (10 dBm = 10 mW).

dB is only confusing if people omit which quantities they are relating. If it's clear like in the case of dBm which relate to 1 mW, it's an awesome tool.

Unfortunately, people omit the quantities all the time. Domain experts assume it when talking to each other, and non-experts repeat it without knowing that it refers to anything at all. (I still don't really know what it means for a sound to have "decibels".)

When referring to sound in the physical world, "decibel" mean dB SPL (sound pressure level). Which is defined as the ratio to the smallest perceivable sound pressure level. Unfortunately that is still a bit underspecified, it may be measured with a frequency weighting like A weighting. And then there is the integration time or other temporal aggregation, but that is separate from decibel/log.

When in analog audio, it usually means dbV, relative to a reference voltage.

And in digital audio, usually dBFS - relative to the maximum amplitude that can be represented.

You can't take the log of a quantity with units like watts. It would be log of some ratio of powers, and then it doesn't matter what unit of power you use because they cancel out. Instead, it matters what the denominator in the ratio is so we're back at needing something confusing like dB :(

That would be dishonest. You don’t adjust input power - you adjust attenuation

EDIT if you did let’s say approximate power, or measure and present the consumed power (as some systems do) you would still be in a situation about how to present this data. Do you present your users with a simple 1-10 (logarithmic) or a 10 digit display which sweeps over vast ranges of uninteresting values.

If you opted for a more compact scientific notation … well guess what that’s also logarithmic but in two parts LOL

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