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While the author is technically right, I must argue that in the area of sound work, decibels make sense. Zero is base level, -3db is half loudness, +3dB is double. There may be a better way to describe loudness, but decibel is good enough.
Sure, perfect sense.
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Eg you could clean up the naming of the variants of the unit, and make it no less useful for RF work, and strictly better in general.
Whining about it makes me really doubt that the OP has any practical experience about the things they're talking about.
Earlier quoted context omitted.
So on my amplifier, 0db is the loudest and -50db, where I usually listen is what? -47db is definitely not twice as loud as -50db, of course.
I'm not confident in what I'm saying here, so please correct me if I'm wrong as I'd like to learn: Human hearing isn't linear in terms of loudness. So a 3db increase in loudness sounds like "an increase", but the pressure is actually double. Hence, it makes sense to use db to describe loudness even in the context of perceived loudness to human-hearing. This is similar to brightness. In photography, "stops" are used t…
Edit: typo
One upside of dB not touched in the article is that it changes multiplication into addition. So you can do math of gains and attenuations in your head a bit more conveniently. Why this would be useful in the age of computers is confusing, but on some radio projects both gains and losses are actually enormous exponents when expressed linearly, so I sort of see why you would switch to logs (aka decibels). Kinda like how you switch to adding logs instead of multiplying a lot of small floats for numerical computing.
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Obviously there are better ways. The author mentioned several. Eg you could clean up the naming of the variants of the unit, and make it no less useful for RF work, and strictly better in general.
Absolutely no one cares about the mathematical purity of a unit like the decibel. It's a hammer that turns log stuff into easy to work with linear stuff. It's x10 because that turns into reasonably easy to use numbers with enough precision to use casually. Otherwise it's just a log ratio. Any suffix is a log ratio to a reference value for the entire system (dBv / dBm etc).
Say in a 50 ohm system I have an level 7 mixer then I need 7dBm into the port. My oscillator kicks out 0dBm (1mW). Then I need a 7dB gain block. I go to the datasheet for the MMIC and pick out a bias network that gives me around 7dB. I grab a eval board for the MMIC, solder the resistors on it, shove this on my VNA and throw 0dBm in one end and see if 7dBm comes out of the other end at the frequency I need.
It's like Laplace. Do you really want to spend hours doing calculus?
Source: actual electrical engineer, not some clueless hobby blogger. I really wish people would stop writing authoritative sounding articles on stuff they clearly have little experience with.
> this is in the same tradition that prompted us to name the “wat” in honor of James Watt. The unit is Watt, not Wat.
Or mine does.
The author seems confused. Decibels aren’t units. They’re a way to express a ratio between a reference value and some other value. They’re used where they are useful.