131–140 of 511 posts
You use a unit that maps well between the thing you want to measure and the thing you want to know about it. If you do this enough with the same until you give it a name. I don’t get the author’s complaint.
Loudness is not measured in dB, but in phon ( https://en.wikipedia.org/wiki/Phon ) or sone ( https://en.wikipedia.org/wiki/Sone ).
The only thing you should know is that any use of bel and thus decibel should ideally have the reference level suffixed (usually in parentheses or subscript), not implied. The absolute sound pressure level is dB(SPL). The human-perceived loudness level is dB(A) and similar. The RMS voltage expressed in power is dB(u) (formerly dB(v), not same as capital dB(V)). And so on. And then each different instance of dB unit i…
This is exactly it. The people who get confused by decibels are treating it a unit in it's own right when it's really just a ratio of some unit.
Yeah. And don't get me started on the folks who think "6dB/octave" is a reasonable thing to say. Which is, apparently, everyone who works with audio filters except me.
How else would you describe what occurs other than 6dB/octave?
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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.
There are better ways, if you optimize for ease of understanding and not ease of use. dB-based units make working between parts of a circuit, different devices etc. a breeze because adding 6dB in one part and removing it in another will result in no change in level. This is something the totally uninitated use every day in audio applications (typically that would be dBFS). What other system do you propose? One where…
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> makes me really doubt that the OP has any practical experience about the things they're talking about. Maybe not, but you can get used to many odd things given enough experience. I totally share the authors view. I don't usually have trouble grasping the definition of a unit, but dBs are just hilariously overloaded. The same symbol can literally mean one of two dimensionless numbers, or one of who knows how many ph…
This like arguing that aspect ratios are stupid and wrong because sometimes they apply to a screen which is really big and sometimes it's really small and sometimes they apply to a physical print or a photo or a billboard or a vintage TV and sometimes it's a jpg or a PNG. Aspect ratio is a ratio. It can be a ratio between pixel counts, or between print dimensions, or physical display dimensions. All of which are usef…
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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.
Sorry but no. 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…
Just read the article.
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Sorry but no. 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…
This is the correct take. These logarithmic scales, in all their various forms, reduce the math involved to something tractable. The reduction is so great that there is no substitute. Griping about the numerous arbitrary reference values and their obscure and ambiguous notations is fine, I suppose, and perhaps fixing this has some value. But ultimately, logarithmic scales are a tool that will be utilized regardless o…
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The same can be said of any unit. "If you just learn to work with it regardless of its weirdness, it's completely normal" doesn't mean the standard isn't ridiculous. I don't think anyone has stated that a logarithmic scale is bad. The type of logarithmic scale changing depending on the field it's being used in, and the non-standard notation (dBm being used instead of dBmW for instance), is just inconsistent for no re…
> I don't see a practical reason why dB's normal use can't have been covered by normal prefixes Because instead of numbers going like 1, 10, 100, 1k, 10k, 100k, 1M, 10M, 100M, 1G, and so on when using prefixes, we get a much more smoother numbers of 0 dB, 10 dB, 20 dB, 30 dB, 40 dB, 50 dB, 60 dB, 70 dB, 80 dB, 90 dB. You can see the the number for the dB get bigger, while when using prefixes the numbers get bigger tw…
Interesting, I don't have any issues with that, and I see the numbers getting bigger and bigger no problemo. Perhaps it's an issue of metric/imperial, as I grew up in a metric country: I have a mental visual model of decades, while dB feels linear. The opposite is likely true e.g. in the US.
> You can plot dB nicely as an axis of a chart
Nothing prevents you from putting the decimal scale on a chart. As a matter of fact, many engineering fields do precisely that. One example that comes to mind are components datasheets: a lot is in log scales, but explicitly so, by putting the 1-10-100 numbers with naught-k-M-G. It's explicitly logarithmic.
Yeah. And don't get me started on the folks who think "6dB/octave" is a reasonable thing to say. Which is, apparently, everyone who works with audio filters except me.
How else would you describe what occurs other than 6dB/octave?