This seems exceedingly ignorant of the work decibels do in telecommunications, RF and fibre engineering. The voltage vs power relationship is something that exists and is a core memory of beginner blunders in the field, but it boils down to a simple 10 vs 20 division operation. Besides that, the decibel simplifies a lot of multiplying very small and very big numbers to summing of two-digit numbers that you can do in your head, and still preserve a big degree of accuracy.
Whining about it makes me really doubt that the OP has any practical experience about the things they're talking about.
svara · 1h ago
> 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 physical units.
That's not normal, something as basic as units is usually very cleanly defined in physics.
Someone in this comment section said it's not a problem because there's usually going to be a suffix that is unambiguous. If that were actually the case, you wouldn't see these types of complaints.
TheOtherHobbes · 16m ago
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 useful in their own way, none of which are directly comparable, all of which are understandable in context.
dB is the same. It's a ratio split into convenient steps - more convenient than Bels would be - that compares two quantities. The quantities can be measured in different units. The units are implied by the context.
The only mild confusion is the relationship between voltage and power ratios. But that's a minor wrinkle, not a showstopping intellectual challenge.
rusk · 1h ago
dB for sound in particular aligns with human experience. The (10 -) 1-10 on a volume knob typically aligns with a logarithmic scale because we hear differences in loudness at an order of magnitude.
A linear volume knob would be frustratingly useless as you would have to crank it many many many times the higher up you want to go. Presumably hundreds of times. A traditional pot couldn’t do that of course but maybe you could satisfy your curiosity with a rotary encoder?
IsTom · 1h ago
You could have log Watts or something, it doesn't have to be dB to be logarithmic.
KeplerBoy · 44m ago
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.
rusk · 1h ago
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
No comments yet
taneq · 1h ago
Ever have a cheap set of external speakers that got super loud in the first quarter turn of the volume knob but were pretty much the same loudness after that? Yeah, linear pot for the volume knob.
No need for an encoder and software, though, logarithmic pots are readily available for precisely this reason. :)
rusk · 1h ago
No I’ve never had one of those LOL
Pots do log and lin scales but they only have a limited angular range.
mattmanser · 49m ago
I've actually noticed this two days ago with some bluetooth headphones and my phone.
The volume control on my android phone was acting just like this when my headphones were connected. When changing the volume with the phone only a small section of the bottom quarter of the volume control actually made a difference, but the volume controls on the headphone themselves were acting "normally".
Usually the phone volume is fine, it only screws up on bluetooth devices (my speakers + my headphones). I have to use the volume control on the device itself to have any good control.
This explains the weird behaviour, the phone volume changes are being sent linearly, but the headphone/speaker settings are correct and being set logarithmically.
i.e. somewhere a developer working on the bluetooth integration didn't understand the difference, screwed up and never tested it. That it's happening to both my Edifier speakers and my cheapo headphones probably means it's on the stock Android end (it's a pixel phone).
holowoodman · 1h ago
Decibels are completely ridiculous. They are only useful if you are a cable monkey just adding and subtracting amplification/dampening factors. As soon as you need to do any kind of non-trivial conversion or computation, dB* is more of a hindrance to understanding and simplicity, because you will always need to look up in some strange table of dB weirdness. Integrate over a spectral power density in dB/Hz? You better convert that to real metric first... Need to solder in a capacitor/resistor/coil as a filter? Better convert to real metric first, because only some pre-made filters are specified in dB (and there are quite a few weird conventions, so you better convert to real metric and check first...).
lifthrasiir · 1h ago
I do see needs for something like decibels. It is a useful way to communicate an inherently logarithmic quantity. The real and IMHO only mistake is that it was described as a typical unit, while it should have been a unit constructor and specially treated in the SI unlike others. (Not in the SI, but the [milli]meter in mmHg etc. and `p` in pH---really p[H+] [1]---are other popular examples of unit constructor.)
[1] To be clear, I'm aware that pH and p[H+] are technically different. But that's orthogonal here.
rocqua · 1h ago
Decibels in gain, those are fine. Though they use a silly base. dBm makes a decent amount of sense, given the RF background.
The fact that decibels work differently for voltage and power is very weird, but understandable in isolation.
But audio decibels are horribly underspecified. And any other use of a decibel as a dimensionful unit is horrible.
I think the RF people know, and that's why they use dBm. Any system that uses decibels as dimensional units needs to make their baseline clear.
I recently saw a fan advertising a low decibel noise "at 3 meters". And it's nice that they advertise (part of) the baseline, but it sweeps a ~10db difference in pressure under the rug, comparee to the standard 1m reference.
mikewarot · 1h ago
Decibels aren't units... they are ratios. The ratio could be gain, or loss, or compared to the noise floor, or the signal of interest, or a standard unit, such as Watts, milliWatts, or microVolts into 50 ohms.
>The fact that decibels work differently for voltage and power is very weird, but understandable in isolation.
If you have a given load, increasing the voltage by a ratio of 10:1 (20 dB) is exactly the same as increasing the power by a ratio of 100:1 (20 dB) (because increasing the voltage ALSO increases the current, and the power is the product of the two)
IsTom · 1h ago
> Decibels aren't units... they are ratios.
Until they are a ratio to a specific arcane reference level as mentioned in the article.
baxuz · 1h ago
You haven't addressed any of the points the author made. You only show habituation and status quo bias.
rusk · 1h ago
Worst metanalysis ever
neuroticnews25 · 1h ago
I think the "whining" is just a stylistic choice and an excuse to talk about the things he finds worth noting. I didn't perceive the tone of the article as negative.
jeroenhd · 1h ago
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 reason.
For a unit of immense scale, I rarely see it used outside of the -100 to 100 range, though. That puts its daily use square in the middle of SIs giga/nano range. I'm sure the formulae are a bit easier by not having to include exponents, but I don't see a practical reason why dB's normal use can't have been covered by normal prefixes.
What sets the dB* aside from other American units is that this one is very close to following standard units. If it weren't for the deci- prefix and the usage of standard units like Watts and Volts ("Bell-horsepowers"), the inconsistencies in practical use would probably have been expected, making learning about the weird intricacies of each field a lot less infuriating.
em3rgent0rdr · 38m ago
> 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 two times in a row and then go back to smaller. With dB you usually just see a number from 0 to around +/- 100 or so. You can plot dB nicely as an axis of a chart and then see the slope of a curve in so many dB per decade.
iLoveOncall · 23m ago
Doesn't OP addres that multiple times in the article? He constantly reminds that the unit means vastly different things based on the domain, and focuses on acoustics after that, which is what every laymen would think about given the mention of decibels.
atoav · 2h ago
As someone who teaches this concept to.. art students I have to say that this complaint sounds a lot like the typical misconceptions and confusions a beginner would have.
Yes, dB is a weird and unintuitive concept and it takes a moment to understand it, but it is also extremely useful once you get it. The fact that people don't write out the reference values does not help either, people will bounce out that audio mix at -20dB when in fact they mean -20dBFS which is referenced to the digital maximum (Full Scale) value. Above 0dBFS you clip the waveform.
People leaving out the reference part is the mean reason for the confusion IMO.
ajuc · 1h ago
You can use logarithmic scale without making it a pseudo-unit that changes the factors depending on the application.
Additionally - attacking people you don't know for ignorance because they have different opinions is very narrowminded.
metalman · 13m ago
sound IS funny, db does work, and for people building the things that produce or record sound. Useing db is just another unit used in engineering.
Now if someone wants to get into the (very facinating), psychoacoustic side of sound, where another unit has been tried, "phons", prounounced
fonz ;) , then it becomes clear that determining sound pressure levels is a tricky thing, as at the low end of perceptable sound the real world power
of the actual sound is miniscule when converted into heat or mechanical power, and at the othete end a amp/speaker set up that was 100% efficient would only need 5 or 10 watts of electricity to power a stadium concert.
we work with what we have, in a past lifeI got a degree in sound engineering, but barely practiced it, found myself way more into enjoying the products that have been built to be used, but am always greatfull to the people who make it possible, who on occasion are entertained by the sometimes exotic ways that I abuse the equipment, as the good ones take pride in having thought of and planed for such things, but do like confermation from the field.
STC ratings anyone?
neepi · 2h ago
I concur. See my other heavily downvoted post. It's a hobby blogger speaking authoritatively about something they have little experience with. This is a curse on any field. It probably looks legitimate to people who have no experience in the field who feel like they are learning something.
fouronnes3 · 1h ago
However you must concede that the perspective of an outsider can be refreshingly eye opening sometimes, even to experts. Especially when it reveals the arcane practices that make a field difficult to learn - for example here the point about the base being too implicit is very valid. The article is perhaps ignorant of a few things, but its criticism shouldn't be dismissed outright IMO. Accepting constructive criticism from someone less experienced at something is a good exercise in humility, and can often help you improve. It's far from a "curse in any field".
neepi · 1h ago
That would assume that the entire world hasn't already tried this a thousand times over.
Measurements are standardised communication tools. If you start changing the definitions, things fall out of the sky and on your head.
yxhuvud · 34m ago
No, changing definitions was exactly how we ended up with SI units. That was a very good (and necessary) thing and definitely not the sky falling down.
baxuz · 1h ago
This mindset is why the US is still using barley seeds as a standardized unit of measure.
dns_snek · 49m ago
You haven't addressed any points the author has made, we don't need to have "experience" in a field to know that ambiguous units are ridiculous and bad.
When I'm buying a piece of string for my garden, I don't need to find an agricultural textbook to know whether "10 meters" in agriculture is the same as "10 meters" in engineering, and whether the definition of "meters" depends on whether the string is made out of cotton or polyester. The same is not true for "decibels". People seem to assume that we're too stupid to understand logarithms, we're not.
Ekaros · 40m ago
Well 10 millimetres of rain is different that 10 millimetres thickness for say branch...
kqr · 27m ago
At first I was going to contradict you but then I realised 10 mm of rain is actually a measure of volume or mass, corresponding to 10 kg, right?
And of course, people use it mainly as a rate, i.e. 10 kg per hour, or per four hours, or six hours, or 24 hours.
And it gets worse when we start talking about snow, the density of which can vary a lot!
Ekaros · 13m ago
Well depending on area you are counting it on. So yes per square meter it would be 10 kg. Your rain gauge might for example not have 10mm spaced markings...
lifthrasiir · 2h ago
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 is simply distinct, only connected by the fact that it represents some ratio in the logarithmic fashion. Treat any new dB unit you haven't seen as an alien.
hashhar · 1h ago
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.
severusdd · 1h ago
While I thoroughly enjoyed reading this piece of internet-rant, I've to argue that dB is still probably the best we have on this!
In RF engineering, expressing signal levels in dBm or gains in dB means you can add values instead of multiplying, which definitely appeared like a huge convenience for my college assignments! A filter with -3 dB loss and an amplifier with +20 dB gain? Just add. You can also use this short notation to represent a variety of things, such as power, gain, attenuation, SPL, etc.
I guess, engineers don’t use dB because they’re masochists (though many of them surely are). They use it because in the messy world of signals, it works. And because nobody knows anything that might work better!
A pet peeve I share! An expanded version of this article should become the article on decibels on Wikipedia.
I've read that article many times over my life and for the first couple times came back thinking I was too dim to understand.
Transparently leading it with "Here's something ridiculously overcomplicated that makes no sense whatsoever..." wouldn't fit Wikipedia's serious voice but actually be pedagogically very helpful.
esperent · 2h ago
There's often a Criticism of... section in Wikipedia pages.
Maybe this blog post could work as a source, although it would be better to find something more established.
fouronnes3 · 2h ago
When I worked on a radar project, my fellow radar engineers (I'm software) used dB a lot. A lot of them would actually agree with the article, but historical sometimes wins even when you're aware of its shortcomings. Aren't we the same in software anyway? The email protocol, terminal escape sequences, the UX of git command line, etc... Each of those could have an "X is ridiculous" blog post (and I would enjoy every single one).
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.
ggm · 2h ago
Do a deep dive into audio vu Meters and how they got calibrated. Without being 100% sure, it's basically a totally subjective model, where back in the 1920s the BBC and some US company decided to assert "like us" and two models persist which have been retconned into some BIPM acceptable ground truth but it basically was "test it against the one we made which works"
The hysteresis in the coil-magnet meter response turned out to be a feature, not a bug.
kazinator · 1h ago
The confusing thing about decibels is not the Watts versus Volts thing.
It is the following.
If you mix two identical signals (same shape and amplitude) which are in phase, you double the voltage, and so quadruple the power, which is +6 dB.
But if you mix two unrelated signals which are about the same in amplitude, their power levels merely add, doubling the power: +3 dB.
cycomanic · 1h ago
That has nothing to do with decibels at all, that's the fundamental physics (or mathematics if you want) of adding waves, i.e. interference.
smat · 3h ago
Great post, the fusion of scale with unit is a mess.
When using it as a factor, for example when describing attenuation or amplification it is fine and can be used similar to percent. Though the author is right - it would be even more elegant to use scientific notation like 1e-4 in this case.
For using it as a unit it would really help to have a common notation for the reference quantity (e.g. 1mW).
But I guess there is no way to change it now that they are established since decades in the way the author describes.
rocqua · 1h ago
Scientific notation would be worse, because you can't add them to get the combined gain. That's where dB's really shine.
calmbonsai · 1h ago
If you're specifying decibels in written form you always include the basis or you're simply being incomplete with your units. I don't understand the complaint there.
In casual conversation, the context implies the basis.
Dealing with decibels is also another shorthand to know the domain has a wide enough value gamut such that logarithmic values (where addition is multiplication) makes sense. See also, the Richter scale.
kazinator · 1h ago
> This means that if you’re talking about watts, +1 bel is an increase of 10×; but if you’re talking about volts, it’s an increase of √10×. This is nuts: it’s akin to saying that the milli- prefix should have different meanings depending on whether we’re talking about meters or liters.
Well no, because even if you are focusing on a signal measured in volts, the bel continues to be related to power and not voltage. As soon as you mention bels or decibels, you're talking about the power aspect of the signal.
If volume were measured in meters, which were understood to be the length of one edge of a cube whose volume is being given, then one millimeter (1/1000th of distance) would have to be interpreted as one billionth (1/1,000,000,000) of the volume.
When you use voltage to convey the amplitude of a signal, it's like giving an area in meters, where it is understood that 100x more meters is 10,000x the area.
There could exist a logarithmic scale in which +3 units represents a doubling of voltage. We just wouldn't be able to call those units decibels.
dj3l4l · 29m ago
The Bel is a unitless quantity. Yes, by convention, in certain fields, it applies to the logarithm of the ratio of powers. But in other fields (for example, quantifying a change in the degree of evidence for a hypothesis, as in Bayesian probability theory) it is applied to a ratio of different quantities (in the Bayesian case, a ratio of probabilities). There is no reason why dB can't be used for any unit, and its meaning is incomplete until the denominator of the ratio within the logarithm is known.
This is the gripe that is being conveyed in this article. Mathematically, the Bel is unitless. It is only by additional context that one can understand the value of the denominator in the logarithm.
jeremyscanvic · 2h ago
Another surprising place decibels pop up, pretty far from loudness related things, is in image comparison metrics. Peak signal-to-noise ratio is mean squared error normalized by a certain peak intensity and it is generally expressed in dB, i.e. as 10 log10(normalized mse). https://en.m.wikipedia.org/wiki/Peak_signal-to-noise_ratio
Edit: typo
rocqua · 1h ago
Decibels make a lot of sense for ratios in any kind of signal processing.
They are not that suited to sound, but sound is generally hard to quantify.
leoedin · 1h ago
I worked in RF (radar) for a while and the dB/dBm is an incredibly useful tool there. It makes reasoning about amplifier chains and insertion loss so much more straightforward. It also means you can talk about transmitters and receivers in a comparable unit - in reality the signals are many many orders of magnitude apart.
nabla9 · 44m ago
Decibel is ridiculously overloaded concept.
It can be used to express and calculate relative change in power, amplitude ratios, and absolute change. All of these are different units and should always use different notation, but sometimes it's skipped.
rebolek · 3h ago
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.
svara · 2h ago
For practical day to day use in very narrow context, yes.
But, what you're saying is only approximately correct (the factor is a bit less than 2) and there are many related fields, even in areas that would be relevant to the physics of sound reproduction, in which the same notation "dB" means something different.
rocqua · 1h ago
That's great, but only if 'Base level' is clear to everyone involved.
Besides the base level, you also need to define what exactly you are measuring. Including the frequency weighting.
This makes a spec sheet that says "this machine produces X dB of sound" effectively useless.
Sharlin · 2h ago
> -3db is half loudness
Sure, perfect sense.
ajuc · 2h ago
> -3db is half loudness, +3dB is double
It isn't tho. It's close but not exactly. And there's nothing about -3 behing half that makes sense except for familiarity (and it's not even wide-spread familiarity - most people wouldn't know how much louder +3dB is).
It's just an unnecesarilly confusing definition that stuck for historic reasons.
kazinator · 2h ago
But, no! -3dB is half power, not half loudness. -3dB down is just slightly less loud.
globular-toast · 1h ago
Exactly. There's no way +3dB is perceptibly twice as loud. That's easy to test for yourself. +10dB is roughly twice as loud.
readthenotes1 · 3h ago
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.
hgo · 2h ago
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 to measure brightness. One stop brighter is technically twice the light, but to the human eye, it just looks "somewhat brighter", as human brightness appreciation is logarithmic, just like "stops" and "db".
No comments yet
rebolek · 2h ago
Again, technically, it is. But ear isn't scientific device, neither is your amplifier. What I was describing is more than an agreement than some precise measurement. 3dB is more or less double the volume but different frequencies have different responses so I really wouldn't want to have some "perfect" way of measuring loudness as it would be so needlessly complicated that it would be useless.
masklinn · 2h ago
3dB is “twice as loud” in that it’s twice (or half) as much power.
Part of the reason why the bel is used is that human perception is closer to logarithmic than linear (weber-fechner law), so a logarithmic scale is a better approximation of “loudness” than a linear one.
coldtea · 1h ago
-47db is double the power. Perceived double loudness would be ~ -40db
timewizard · 2h ago
Human hearing perception response is logarithmic. This is part of the reason we use the unit. Our senses naturally work in that domain.
coldtea · 1h ago
> Human hearing perception response is logarithmic.
It is, but -50db to -47db (+3db) is not double perceived loudness. It's double power. About +6 or even +10db would be double perceived loudness.
hashhar · 57m ago
Going from -50dB to -44dB is a much louder change than going from -6dB to 0dB.
Human hearing is logarithmic. The dB is measuring ratio of sound pressure level and it's accurate that +/-3dB is almost doubling/halving of the SPL.
bloppe · 2h ago
I mean, it should be, unless your amplifier is taking its own liberties with the definition of dB.
em3rgent0rdr · 1h ago
> For some reason, the bel — again, what started as a sensible 10× increment — was soon deemed too big to use. I don’t quite know why: in other aspects of life, decimal notation suits us just fine.
Decimal notation can be a tad cumbersome to write and speak. Meanwhile, decibel usage commonly results in nice simple numbers that range between 0 and 100, with the fractional digits often being too insignificant to say out loud. For instance, the dynamic range of 16-bit audio (which is generally all the range that our ears care about) is 96 dB, while volume increments smaller than 1 dB aren't really noticeable, so decibel makes it easy to communicate volume levels without saying "point" or writing a "." or breaking out exponential notation. Even in fields other than audio the common ranges also conveniently will be around 1 dB for being on the verge of significance to around 100 dB or 200 dB for the upper range. (Also the whole power vs root-power caveat is simply something users of dB have to be cognizant of because we need to stick with one or the other to make consistent comparisons, and at the end of the day physical things hapen with power.) So while decibels may seem ridiculous, they actually are quite convenient for dealing with logarithmically-varying numbers in convient range from 1 dB to around 100 dB or so in many engineering fields.
em3rgent0rdr · 24m ago
Its like why we use percent from 0% to 100% instead of speaking of ratios from 0 point something to 1.
nyanpasu64 · 45m ago
I have a vague report that "root-power" or voltage-like quantities (20 dB per order of magnitude) are signed or vector-like, while power-like quantities are unsigned scalars?
amai · 20m ago
Fahrenheit on the other hand makes sense...
bob1029 · 1h ago
I think dB is a good way to represent certain user interfaces. I've always preferred to operate my audio equipment using a logarithmic scale. Changing the volume is much more intuitive to me this way than with some linear 0-100 mapping.
cousin_it · 1h ago
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.
jpc0 · 10m ago
How else would you describe what occurs other than 6dB/octave?
ziofill · 2h ago
The nice thing about dBs is that they are logarithms: successive applications of gain/attenuation are easily computed by just adding up the dBs. (but yes, I agree that there should be more consistency in their definition)
badlibrarian · 1h ago
Horsepower is a unit of measurement. There's hp and bhp and hpE and...
"Other names for the metric horsepower are the Italian cavallo vapore (cv), Dutch paardenkracht (pk), the French cheval-vapeur (ch), the Spanish caballo de vapor and Portuguese cavalo-vapor (cv), the Russian лошадиная сила (л. с.), the Swedish hästkraft (hk), the Finnish hevosvoima (hv), the Estonian hobujõud (hj), the Norwegian and Danish hestekraft (hk), the Hungarian lóerő (LE), the Czech koňská síla and Slovak konská sila (k or ks), the Serbo-Croatian konjska snaga (KS), the Bulgarian конска сила, the Macedonian коњска сила (KC), the Polish koń mechaniczny (KM) (lit. 'mechanical horse'), Slovenian konjska moč (KM), the Ukrainian кінська сила (к. с.), the Romanian cal-putere (CP), and the German Pferdestärke (PS)." [1]
Decibel is not a unit of measurement. Decibels are a relative measurement. It tells you how much louder or powerful something is relative to something else. And frankly far less ridiculous than horsepower, which has a hilarious Wiki article if you read it with a critical mindset.
Deriving some of the constants without Googling is a fun exercise to verify that you're not as smart as you think you are. "Hydraulic horsepower = pressure (pounds per square inch) * flow rate (gallons per minute) / 1714"
> "Other names for the metric horsepower are [...]"
I'm not clear on what point you think you're making. Is it interesting that the same thing might have different names in different languages?
That subsection of the article, by the way, is obviously lying:
> The various units used to indicate this definition (PS, KM, cv, hk, pk, k, ks and ch) all translate to horse power in English.
cv and ch translate to steam horse, which isn't hard to see even if you only speak English. What does "vapor" mean to you?
The opening of the article does suggest some problems, though not problems that wouldn't apply to the word "ounce". But you seem to have pulled an extended quote describing a completely expected state of affairs, while ignoring this:
> There are many different standards and types of horsepower. Two common definitions used today are the imperial horsepower as in "hp" or "bhp" which is about 745.7 watts, and the metric horsepower as in "cv" or "PS" which is approximately 735.5 watts. The electric horsepower "hpE" is exactly 746 watts, while the boiler horsepower is 9809.5 or 9811 watts, depending on the exact year.
I don't get it.
badlibrarian · 1h ago
That a unit of power has a dozen metric abbreviations and converts to watts at different values depending on what it is measuring (and when) is precisely the point.
Decibels aren't ridicluous or a unit of measure. Horsepower, however...
yuvadam · 2h ago
Decibels aren't actually that ridiculous if you just accept them as plain logarithmic ratios, between your signal and the noise floor or some other signal. (Or between anything else, really.)
3dB is roughly double, 10dB is 10x, but only sounds about twice as loud because our ears are weird.
undebuggable · 1h ago
If decibels in acoustics confuse you, try learning decibels in optical communication. That's a witchcraft.
thrdbndndn · 2h ago
> this is in the same tradition that prompted us to name the “wat” in honor of James Watt.
As for the reason, if I have to guess, is because "decibel" looks better than "decibell".
(Keep in mind decibel was actually renamed from the previous unit called "Transmission Unit" and was meant to be used as the main unit even at the beginning. "bel" was simply derived/implied from it, not the other way around).
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.
coolcase · 2h ago
They are units too. When you have regulations relating to sound they will say how many dB the limit is.
neepi · 2h ago
No. dB is not a unit. If it's quoted as a unit, then the person using it doesn't know what they are doing. dBx where x is some reference value is a unit and that means dB relative to the reference unit. So dBm/dBv etc are units. dB is not.
Mathematically, dB is the ratio between two unit values and for example if you divide metres by metres you cancel the units.
qmmmur · 28m ago
Exactly. If someone says that "this plane is about 130dB" what they mean is in reference to 0dB given 0dB is the threshold of human hearing. It seems most people are confused by dB because they don't understand it provides a logarithmically scaled unit compared to a reference which happens to be quite useful for something like audio where our perceptual models are stacked with these types of curves.
formerly_proven · 2h ago
I've never seen dB being used like that in anything remotely official.
That's hilarious, though they do seem to get it right on the other, more in-depth pages.
throwaway290 · 1h ago
Yep, the NIOSH meter app they recommend uses dB(A).
rocqua · 1h ago
dBs are so often used as units. That's 80% of the complaint in the article.
The fact that dBs aren't units, but are used like units, is the point being made.
atoav · 2h ago
But dB is not a unit, it is a multiplier. dB on its own is unitless and if we say "X is reduced by 6 dB" you know that the value of X is half of what it was before (×0.5) if something is amplified by 6 dB it is double of what it was before (×2.0)¹
Note that the unit only starts to play a role when you reference your dB value to some absolute maximum, e.g.:
dBV which is referenced to 1V RMS
dBu which is referenced to 0.775V RMS (1mW into a typical audio system impedance of 600 Ohms)
dBFS which is referenced to a digital audio maximum level (0dBFS) beyond which your numeric range would clip (meaning all practical values will be negative)
dBSPL which is refrenced to the Sound Pressure Level that is at the lower edge of hearing (0 dBSPL), this is what people mean when they say the engine of a starting airplane is 120dB loud
Now dB is extremely useful in all fields where your values span extremely big ranges, like in audio engineering, where the ratio between high and low values can easily have a ratio of 1:10 Millions. So unless you want people to count zeroes behind the comma, dB is the way to go.
When we think about the connection between analog and digital audio dB is useful because despite you having volts on the one side and bits on the other side a 6dB change on one side translates to a 6dB change on the other, the reference has just changed. If we had no dB we would have to do conversions constantly.
Going from multiplier x to dB: 20×log₁₀(x)
Going from dB to multiplier x: 10^(x/20)
If you use dB to describe the power of a signal that is slightly different (you use 10 instead of 20 as multiplier/divisor)
But you can see, dB is just a way to describe a unreferenced size change in a uniform way or to describe a referenced ratio. And then it would be good to know what that reference is. So if someone says a thing has 40dB you they forgot to tell you the unit.
¹ this is true for the amplitude of a signal and differs when we talk about the power of a signal, where 3dB is a doubling/halving.
roelschroeven · 1h ago
> If you use dB to describe the power of a signal that is slightly different (you use 10 instead of 20 as multiplier/divisor)
This is the part I don't get. This is the part where "dB is just a multiplier" falls short. It's there to "so that the related power and root-power levels change by the same value in linear systems" (that's how Wikipedia formulates it). Why is that even something you would want? Isn't it much more logical, intuitive, consistent and useful to reflect the fact of power being proportional to the square of the signal in it having double the dB value?
rocqua · 1h ago
> But dB is not a unit, it is a multiplier. dB on its own is unitless.
The point of the article is exactly that this should be the case. But it ends up not being the case.
Mostly because people use dB with reference to some assumed baseline. But also because a 20db change could be a 10x change conpared to baseline, or a 100x change compared to baseline, depending on what unit you are measuring in.
mikewarot · 1h ago
20 dB is always the same, actually. If you multiply voltage (and thus current as well) by 10:1 (20 db) the power is multiplied by 100:1 (also 20 dB)
atoav · 1h ago
Yes but my conclusion would not be that Decibels are ridiculous, but that "People don't understand Decibels".
Decibels are okay. They are useful. They work. The problem is that people use referenced decibel values without adding anything that would allow us to understand which reference was used.
Maybe one could have come up with a better numeric way of doing the same thing (I am missing a proposal for this in the blog post), but then you'd have the XKCD-yet-another-standard problem. Everything uses dB for ages now, so dB it is or you need to convert between one and another all the time.
As an audio engineer I have no issue with dB as a unit. It is much better than using raw amplitude numbers.
formerly_proven · 2h ago
Decibels make sense and it’s usually only laymen who use only „dB“. I’d be surprised if you’d find „-45 dB“ as the specification for a microphone. Here’s two random examples:
Sensitivity at 1 kHz into 1 kohm: 23 mV/Pa ≙ –32.5 dBV ± 1 dB
Sensitivity: -56 dBV/Pa (1.85 mV)
taneq · 1h ago
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.
varjag · 1h ago
Decibels are not anywhere near as ridiculous as Marketing Kilobytes introduced in the 1990s. Pot, meet kettle.
timewizard · 2h ago
> That said, I don’t know how to pronounce “3e5”
"Three to the exponent of five." Or "Three Exponent Five." Or "Three Exp Five."
> Seeing this, some madman decided that 1 bel should always describe a 10× increase in power, even if it’s applied to another base unit. This means that if you’re talking about watts, +1 bel is an increase of 10×; but if you’re talking about volts, it’s an increase of √10×
This is power vs. amplitude. This is the specific reason the dB is so useful in these systems.
> the value is meaningless unless we know the base unit and the reference point
No you just need to know if you have a power or a root-power quantity. Which should generally be obvious.
> > That said, I don’t know how to pronounce “3e5”
> "Three to the exponent of five." Or "Three Exponent Five." Or "Three Exp Five."
Somehow, you need to distinguish between 3^5 (=243), 3 x e^5 (=~445.24), and 3 x 10^5 (=300,000).
I'd pronounce "3e5" and "three times ten to the 5" in most cases.
timewizard · 1h ago
> 3^5 (=243)
Three to the power of five.
> 3 x e^5
Three times the fifth power of e. Or Three times e's fifth power.
> 3 x 10^5 (=300,000).
Three to the exponent of five.
A calculator user once suggested "decapower." I think exponent and "EXP" are comfortable and easy to say and are ingrained to most old school calculator users. Which is also why I think "e's fifth power" can be a more natural sequence.
ggm · 2h ago
> No you just need to know if you have a power or a root-power quantity. Which should generally be obvious.
There has to be a Yogi Berra witticism about obvious things. Suffice to say fools like me work unadvisedly in spaces where this kind of axiom isn't obvious, because we're simpletons.
Whining about it 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 physical units.
That's not normal, something as basic as units is usually very cleanly defined in physics.
Someone in this comment section said it's not a problem because there's usually going to be a suffix that is unambiguous. If that were actually the case, you wouldn't see these types of complaints.
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 useful in their own way, none of which are directly comparable, all of which are understandable in context.
dB is the same. It's a ratio split into convenient steps - more convenient than Bels would be - that compares two quantities. The quantities can be measured in different units. The units are implied by the context.
The only mild confusion is the relationship between voltage and power ratios. But that's a minor wrinkle, not a showstopping intellectual challenge.
A linear volume knob would be frustratingly useless as you would have to crank it many many many times the higher up you want to go. Presumably hundreds of times. A traditional pot couldn’t do that of course but maybe you could satisfy your curiosity with a rotary encoder?
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.
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
No comments yet
No need for an encoder and software, though, logarithmic pots are readily available for precisely this reason. :)
Pots do log and lin scales but they only have a limited angular range.
The volume control on my android phone was acting just like this when my headphones were connected. When changing the volume with the phone only a small section of the bottom quarter of the volume control actually made a difference, but the volume controls on the headphone themselves were acting "normally".
Usually the phone volume is fine, it only screws up on bluetooth devices (my speakers + my headphones). I have to use the volume control on the device itself to have any good control.
This explains the weird behaviour, the phone volume changes are being sent linearly, but the headphone/speaker settings are correct and being set logarithmically.
i.e. somewhere a developer working on the bluetooth integration didn't understand the difference, screwed up and never tested it. That it's happening to both my Edifier speakers and my cheapo headphones probably means it's on the stock Android end (it's a pixel phone).
[1] To be clear, I'm aware that pH and p[H+] are technically different. But that's orthogonal here.
But audio decibels are horribly underspecified. And any other use of a decibel as a dimensionful unit is horrible. I think the RF people know, and that's why they use dBm. Any system that uses decibels as dimensional units needs to make their baseline clear.
I recently saw a fan advertising a low decibel noise "at 3 meters". And it's nice that they advertise (part of) the baseline, but it sweeps a ~10db difference in pressure under the rug, comparee to the standard 1m reference.
>The fact that decibels work differently for voltage and power is very weird, but understandable in isolation.
If you have a given load, increasing the voltage by a ratio of 10:1 (20 dB) is exactly the same as increasing the power by a ratio of 100:1 (20 dB) (because increasing the voltage ALSO increases the current, and the power is the product of the two)
Until they are a ratio to a specific arcane reference level as mentioned in the article.
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 reason.
For a unit of immense scale, I rarely see it used outside of the -100 to 100 range, though. That puts its daily use square in the middle of SIs giga/nano range. I'm sure the formulae are a bit easier by not having to include exponents, but I don't see a practical reason why dB's normal use can't have been covered by normal prefixes.
What sets the dB* aside from other American units is that this one is very close to following standard units. If it weren't for the deci- prefix and the usage of standard units like Watts and Volts ("Bell-horsepowers"), the inconsistencies in practical use would probably have been expected, making learning about the weird intricacies of each field a lot less infuriating.
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 two times in a row and then go back to smaller. With dB you usually just see a number from 0 to around +/- 100 or so. You can plot dB nicely as an axis of a chart and then see the slope of a curve in so many dB per decade.
Yes, dB is a weird and unintuitive concept and it takes a moment to understand it, but it is also extremely useful once you get it. The fact that people don't write out the reference values does not help either, people will bounce out that audio mix at -20dB when in fact they mean -20dBFS which is referenced to the digital maximum (Full Scale) value. Above 0dBFS you clip the waveform.
People leaving out the reference part is the mean reason for the confusion IMO.
Additionally - attacking people you don't know for ignorance because they have different opinions is very narrowminded.
Measurements are standardised communication tools. If you start changing the definitions, things fall out of the sky and on your head.
When I'm buying a piece of string for my garden, I don't need to find an agricultural textbook to know whether "10 meters" in agriculture is the same as "10 meters" in engineering, and whether the definition of "meters" depends on whether the string is made out of cotton or polyester. The same is not true for "decibels". People seem to assume that we're too stupid to understand logarithms, we're not.
And of course, people use it mainly as a rate, i.e. 10 kg per hour, or per four hours, or six hours, or 24 hours.
And it gets worse when we start talking about snow, the density of which can vary a lot!
In RF engineering, expressing signal levels in dBm or gains in dB means you can add values instead of multiplying, which definitely appeared like a huge convenience for my college assignments! A filter with -3 dB loss and an amplifier with +20 dB gain? Just add. You can also use this short notation to represent a variety of things, such as power, gain, attenuation, SPL, etc.
I guess, engineers don’t use dB because they’re masochists (though many of them surely are). They use it because in the messy world of signals, it works. And because nobody knows anything that might work better!
I've read that article many times over my life and for the first couple times came back thinking I was too dim to understand.
Transparently leading it with "Here's something ridiculously overcomplicated that makes no sense whatsoever..." wouldn't fit Wikipedia's serious voice but actually be pedagogically very helpful.
Maybe this blog post could work as a source, although it would be better to find something more established.
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.
The hysteresis in the coil-magnet meter response turned out to be a feature, not a bug.
It is the following.
If you mix two identical signals (same shape and amplitude) which are in phase, you double the voltage, and so quadruple the power, which is +6 dB.
But if you mix two unrelated signals which are about the same in amplitude, their power levels merely add, doubling the power: +3 dB.
When using it as a factor, for example when describing attenuation or amplification it is fine and can be used similar to percent. Though the author is right - it would be even more elegant to use scientific notation like 1e-4 in this case.
For using it as a unit it would really help to have a common notation for the reference quantity (e.g. 1mW).
But I guess there is no way to change it now that they are established since decades in the way the author describes.
In casual conversation, the context implies the basis.
Dealing with decibels is also another shorthand to know the domain has a wide enough value gamut such that logarithmic values (where addition is multiplication) makes sense. See also, the Richter scale.
Well no, because even if you are focusing on a signal measured in volts, the bel continues to be related to power and not voltage. As soon as you mention bels or decibels, you're talking about the power aspect of the signal.
If volume were measured in meters, which were understood to be the length of one edge of a cube whose volume is being given, then one millimeter (1/1000th of distance) would have to be interpreted as one billionth (1/1,000,000,000) of the volume.
When you use voltage to convey the amplitude of a signal, it's like giving an area in meters, where it is understood that 100x more meters is 10,000x the area.
There could exist a logarithmic scale in which +3 units represents a doubling of voltage. We just wouldn't be able to call those units decibels.
This is the gripe that is being conveyed in this article. Mathematically, the Bel is unitless. It is only by additional context that one can understand the value of the denominator in the logarithm.
Edit: typo
They are not that suited to sound, but sound is generally hard to quantify.
It can be used to express and calculate relative change in power, amplitude ratios, and absolute change. All of these are different units and should always use different notation, but sometimes it's skipped.
But, what you're saying is only approximately correct (the factor is a bit less than 2) and there are many related fields, even in areas that would be relevant to the physics of sound reproduction, in which the same notation "dB" means something different.
This makes a spec sheet that says "this machine produces X dB of sound" effectively useless.
Sure, perfect sense.
It isn't tho. It's close but not exactly. And there's nothing about -3 behing half that makes sense except for familiarity (and it's not even wide-spread familiarity - most people wouldn't know how much louder +3dB is).
It's just an unnecesarilly confusing definition that stuck for historic reasons.
-47db is definitely not twice as loud as -50db, of course.
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 to measure brightness. One stop brighter is technically twice the light, but to the human eye, it just looks "somewhat brighter", as human brightness appreciation is logarithmic, just like "stops" and "db".
No comments yet
Part of the reason why the bel is used is that human perception is closer to logarithmic than linear (weber-fechner law), so a logarithmic scale is a better approximation of “loudness” than a linear one.
It is, but -50db to -47db (+3db) is not double perceived loudness. It's double power. About +6 or even +10db would be double perceived loudness.
Human hearing is logarithmic. The dB is measuring ratio of sound pressure level and it's accurate that +/-3dB is almost doubling/halving of the SPL.
Decimal notation can be a tad cumbersome to write and speak. Meanwhile, decibel usage commonly results in nice simple numbers that range between 0 and 100, with the fractional digits often being too insignificant to say out loud. For instance, the dynamic range of 16-bit audio (which is generally all the range that our ears care about) is 96 dB, while volume increments smaller than 1 dB aren't really noticeable, so decibel makes it easy to communicate volume levels without saying "point" or writing a "." or breaking out exponential notation. Even in fields other than audio the common ranges also conveniently will be around 1 dB for being on the verge of significance to around 100 dB or 200 dB for the upper range. (Also the whole power vs root-power caveat is simply something users of dB have to be cognizant of because we need to stick with one or the other to make consistent comparisons, and at the end of the day physical things hapen with power.) So while decibels may seem ridiculous, they actually are quite convenient for dealing with logarithmically-varying numbers in convient range from 1 dB to around 100 dB or so in many engineering fields.
"Other names for the metric horsepower are the Italian cavallo vapore (cv), Dutch paardenkracht (pk), the French cheval-vapeur (ch), the Spanish caballo de vapor and Portuguese cavalo-vapor (cv), the Russian лошадиная сила (л. с.), the Swedish hästkraft (hk), the Finnish hevosvoima (hv), the Estonian hobujõud (hj), the Norwegian and Danish hestekraft (hk), the Hungarian lóerő (LE), the Czech koňská síla and Slovak konská sila (k or ks), the Serbo-Croatian konjska snaga (KS), the Bulgarian конска сила, the Macedonian коњска сила (KC), the Polish koń mechaniczny (KM) (lit. 'mechanical horse'), Slovenian konjska moč (KM), the Ukrainian кінська сила (к. с.), the Romanian cal-putere (CP), and the German Pferdestärke (PS)." [1]
Decibel is not a unit of measurement. Decibels are a relative measurement. It tells you how much louder or powerful something is relative to something else. And frankly far less ridiculous than horsepower, which has a hilarious Wiki article if you read it with a critical mindset.
Deriving some of the constants without Googling is a fun exercise to verify that you're not as smart as you think you are. "Hydraulic horsepower = pressure (pounds per square inch) * flow rate (gallons per minute) / 1714"
[1] https://en.wikipedia.org/wiki/Horsepower
I'm not clear on what point you think you're making. Is it interesting that the same thing might have different names in different languages?
That subsection of the article, by the way, is obviously lying:
> The various units used to indicate this definition (PS, KM, cv, hk, pk, k, ks and ch) all translate to horse power in English.
cv and ch translate to steam horse, which isn't hard to see even if you only speak English. What does "vapor" mean to you?
The opening of the article does suggest some problems, though not problems that wouldn't apply to the word "ounce". But you seem to have pulled an extended quote describing a completely expected state of affairs, while ignoring this:
> There are many different standards and types of horsepower. Two common definitions used today are the imperial horsepower as in "hp" or "bhp" which is about 745.7 watts, and the metric horsepower as in "cv" or "PS" which is approximately 735.5 watts. The electric horsepower "hpE" is exactly 746 watts, while the boiler horsepower is 9809.5 or 9811 watts, depending on the exact year.
I don't get it.
Decibels aren't ridicluous or a unit of measure. Horsepower, however...
3dB is roughly double, 10dB is 10x, but only sounds about twice as loud because our ears are weird.
The unit is Watt, not Wat.
Or mine does.
For reference: https://www.destroyallsoftware.com/talks/wat
As for the reason, if I have to guess, is because "decibel" looks better than "decibell".
(Keep in mind decibel was actually renamed from the previous unit called "Transmission Unit" and was meant to be used as the main unit even at the beginning. "bel" was simply derived/implied from it, not the other way around).
“The phon is a logarithmic unit of loudness level for tones and complex sounds.”
https://en.wikipedia.org/wiki/Phon
They’re used where they are useful.
Mathematically, dB is the ratio between two unit values and for example if you divide metres by metres you cancel the units.
Maybe the reference is implied though?
The fact that dBs aren't units, but are used like units, is the point being made.
Note that the unit only starts to play a role when you reference your dB value to some absolute maximum, e.g.:
Now dB is extremely useful in all fields where your values span extremely big ranges, like in audio engineering, where the ratio between high and low values can easily have a ratio of 1:10 Millions. So unless you want people to count zeroes behind the comma, dB is the way to go.When we think about the connection between analog and digital audio dB is useful because despite you having volts on the one side and bits on the other side a 6dB change on one side translates to a 6dB change on the other, the reference has just changed. If we had no dB we would have to do conversions constantly.
Going from multiplier x to dB: 20×log₁₀(x)
Going from dB to multiplier x: 10^(x/20)
If you use dB to describe the power of a signal that is slightly different (you use 10 instead of 20 as multiplier/divisor)
But you can see, dB is just a way to describe a unreferenced size change in a uniform way or to describe a referenced ratio. And then it would be good to know what that reference is. So if someone says a thing has 40dB you they forgot to tell you the unit.
¹ this is true for the amplitude of a signal and differs when we talk about the power of a signal, where 3dB is a doubling/halving.
This is the part I don't get. This is the part where "dB is just a multiplier" falls short. It's there to "so that the related power and root-power levels change by the same value in linear systems" (that's how Wikipedia formulates it). Why is that even something you would want? Isn't it much more logical, intuitive, consistent and useful to reflect the fact of power being proportional to the square of the signal in it having double the dB value?
The point of the article is exactly that this should be the case. But it ends up not being the case. Mostly because people use dB with reference to some assumed baseline. But also because a 20db change could be a 10x change conpared to baseline, or a 100x change compared to baseline, depending on what unit you are measuring in.
Decibels are okay. They are useful. They work. The problem is that people use referenced decibel values without adding anything that would allow us to understand which reference was used.
Maybe one could have come up with a better numeric way of doing the same thing (I am missing a proposal for this in the blog post), but then you'd have the XKCD-yet-another-standard problem. Everything uses dB for ages now, so dB it is or you need to convert between one and another all the time.
As an audio engineer I have no issue with dB as a unit. It is much better than using raw amplitude numbers.
Sensitivity at 1 kHz into 1 kohm: 23 mV/Pa ≙ –32.5 dBV ± 1 dB
Sensitivity: -56 dBV/Pa (1.85 mV)
"Three to the exponent of five." Or "Three Exponent Five." Or "Three Exp Five."
> Seeing this, some madman decided that 1 bel should always describe a 10× increase in power, even if it’s applied to another base unit. This means that if you’re talking about watts, +1 bel is an increase of 10×; but if you’re talking about volts, it’s an increase of √10×
This is power vs. amplitude. This is the specific reason the dB is so useful in these systems.
> the value is meaningless unless we know the base unit and the reference point
No you just need to know if you have a power or a root-power quantity. Which should generally be obvious.
https://en.wikipedia.org/wiki/Power,_root-power,_and_field_q...
> "Three to the exponent of five." Or "Three Exponent Five." Or "Three Exp Five."
Somehow, you need to distinguish between 3^5 (=243), 3 x e^5 (=~445.24), and 3 x 10^5 (=300,000).
I'd pronounce "3e5" and "three times ten to the 5" in most cases.
Three to the power of five.
> 3 x e^5
Three times the fifth power of e. Or Three times e's fifth power.
> 3 x 10^5 (=300,000).
Three to the exponent of five.
A calculator user once suggested "decapower." I think exponent and "EXP" are comfortable and easy to say and are ingrained to most old school calculator users. Which is also why I think "e's fifth power" can be a more natural sequence.
There has to be a Yogi Berra witticism about obvious things. Suffice to say fools like me work unadvisedly in spaces where this kind of axiom isn't obvious, because we're simpletons.