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.

Right, but in this case they only give you one of the two numbers. Imagine being told that your TV had an aspect ration of ":16", and you just have to magically know what the other number means in the context. And sometimes ":16" actually means ":4", because quadratic mumble mumble, and sometimes the number is scaled according to some other "how big it seems to humans" factor; all of which you also just have to know in context.

We kind of have that with people talking about a screen or image being "2k" and then expect you to infer what the actual resolution and aspect ratio is from context.

RE: Yes, I was able to read and understand the article. I also have 8 years of EE. Ratio is still a single number in the end. You can have an actual size of a monitor 1600 x 1200 and the ratio of sides is 1600/1200, which is just a single number. You can express it in multiple ways. You still need at least one size + understanding of what the aspect ratio is used to describe in a particular situation (units (mm, px, ...), ...) to be able to calculate the complete dimensions of a monitor screen.

Same issue with % or ppm, or whatever.

You always need a defintition to understand what the numbers are abstracting in any particular situation.

1. 10x more power than what? It changes, and you Just Have to Know.

2. It's 10x more power; so if you're measuring power, like pascals, then 10db means 10x more pascals. But if you're measuring something like voltage, then it's not 10x more voltage, it's something else.

3. And if you're talking about sound, you may be talking about objective power; or you might be talking about how much more powerful it seems to humans.

That gives me an idea - explicitly state the basis and multiply. So the current notation "3 dBm" should instead be "1 mW × 3 dB".

Furthermore, any addition in the logarithmic domain must be grouped, like: "3 dBm + 5 dB" --> "1 mW × (3 dB + 5 dB)".

https://trac.ffmpeg.org/ticket/11279

https://trac.ffmpeg.org/ticket/11284

dB SPL and dB(A) are not ratios, they're absolute. You can derive them from a ratio and a reference level, but the former can be expressed in Pascal and the latter relates to Pascals after applying a perceptual correction function.

Similarly, dBm can be expressed as an absolute potential in Volt.

And then you've got the cases where it really just is a ratio (one of two possibilities).

You'll see all of these called "decibels".

You see why people are irritated?

And yeah, the issue is when people forget to use physical units, like if they say it's 30 degrees outside amd not saying C F or K or latitude.

The historical context is a bit meaningless as well since the main application for the OG dB is 101 classes.

This is the absurd part. There do exist other ratios that masquerade as units, e.g. specific gravity, and its meaning also changes depending on what you’re using it for - liquids are compared to pure water at 4 C, gases are compared to air at 20 C. As the parent comment points out, you can get used to things with experience. That doesn’t make them any less absurd. Look at Fahrenheit, for example. I’m American, and I still think it’s absurd, but because I’m extremely used to it, it feels natural.

What do you find absurd about Fahrenheit?

If it is that its 0 point is not absolute 0 then I think you can make a good case, at least for scientific work. It's a bit harder to make the case for absolute 0 being the 0 point a scale for ordinary day to day use since all temperatures most people deal with will be 3 digit numbers (and making you degree large won't help because people will still need 3 digit number--they just won't be integers any more).

If you find it absurd compared to Celsius then I think it is hard to make a convincing case. They are both scales with a 0 point way above absolute 0, differing only on where they put their 0 point and the size of the degree. (They originally differed on direction, with Celsius putting 0 at the boiling point of water and setting the degree size so that water froze at 100, but Celsius soon came to his sense and flipped so the numbers went up as it got hotter).

Fahrenheit set 0 at the coldest temperature he could make in his lab and tried to set 100 at body temperature. Celsius (once he got the direction fixed) set 0 at water freezing and 100 at water boiling.

That gives Fahrenheit a smaller degree and puts the range of temperatures most people deal with most of the time above 0.

Celsius made it easier to memorize two temperatures that are very significant in many human activities, namely the freezing point of water and the boiling point of water (although the latter is probably less important...generally most people only deal with boiling water when they are trying to boil water and don't need to care about the temperature. It's not like freezing which can happen naturally and so people often need to monitor temperature to find out if there is danger of freezing).

But that 0 point in Celsius means that a lot of people have to regularly deal with negative temperature which is a little annoying.

The metric system chose Celsius, but I've not been able to find any compelling technical reason for that. A metric system with Fahrenheit would have fine too.

Note that unlike mass, length, area, and volume units pre-metric systems generally only had one temperature unit. There was nothing in temperature like miles, yards, inches, feet, furlongs, etc. for length and gallons, pints, cups, etc. for volume. A system that went with one single length unit (the meter) and one single volume unit (the liter) and then derived larger and smaller units from those using consistent ratios and prefixes that were the same across different types of units was a massive simplification.

I asked an LLM why metric went with Celsius and got a lot of circular reasons. For example it cited that various thermodynamic forumals would not work with F degrees because the Boltzman constant is defined in the SI system using K. But the Boltzman constant is defined that way because SI uses the metric system. In an F based metric system the Boltzman constant would be defined in R and everything would work fine.

The non-circular reasons it suggested were also not satisfactory. One was that C was more common than F in Europe at the time the metric system was created, which technically does answer the question I asked but then raises the question of why C became more common pre-metric.

It also suggested that having water freeze at 0 and boil at 100 fits in better with a decimal system which doesn't really make a lot of sense.

As for why C became more popular than F pre-metric it suggests that the 0 and 100 points were easier to reproduce. Fahrenheit's choice of body temperature for the 100 point was definitely a mistake as it is too fuzzy (it was even dumber than metric's initial choice for the meter as 1/10000000th of the distance from the distance from the North Pole to the equator along the meridian passing through Paris).

Freezing and boiling of water do take some care to use (you need to control pressure and contaminants) but are going to be more consistent that body temperature.

But there is no reason I can see that the fuzziness in Fahrenheit's 100 point couldn't have been fixed by simply changing the defining points from 0 and 100 to water freezes at 32 and boils at 212. Yes, it is not as easy to memorize as 0 and 100 but does let us have a scale where most temperatures dealt with by most people most of the time are 2 or 3 digit positive integers.

I understand the argument for Fahrenheit having better granularity with whole numbers in the human range of the scale. I don’t think that justifies everything else about it, especially considering the rest of the world somehow manages with Celsius.

But joking aside, While you do point out some of the worst offences, 5280 foot in mile is a special sort of stupid. I do wish we would have metriced around base 12 like a lot of the old measurements were instead of base 10.

Base 10 sort sucks for quantities. I mean, we are all used to it and it works well enough, and having a proper base system is far far better than the alternative coughs roman numbers. but base 10 is a quirk of chance, we very nearly ended up with base 12, and I think we would have been slightly richer for it.

And before you give me the tired ol "BuT yOu HaVe TeN FiNgErS", no, you have 8 fingers and 3 bones per finger, a very common early way of counting for them who had to actually count large numbers(sheep herders) was to use your thumb to mark the spot and count on your finger bones, 12 on one hand, and 12 on the other, this is why 144 (a gross) is so common.

Update: I take back what I said about the mile.

    /usr/games/factor 5280
    5280: 2 2 2 2 2 3 5 11

Please clarify what you mean by this. Let me call your system altmetric for clarity.

Surely, you want altmetric to use prefixes that are powers of 12 - okay, fair enough. I see the analogy with the fact that 1 foot = 12 inches, and how base-60 is used in minutes and seconds (also arcminutes and arcseconds). (But why no thirds and fourths?)

But do you want altmetric to require all numbers to be expressed in base-12? If no, then your system does not allow easy conversion. In real metric, the fact that 1.234 kg = 1234 g is a trivial conversion, and it turns a calculation problem into a mere syntactical transformation. If yes and you require base-12, then you've basically alienated everyone. It would be about as weird as telling construction workers and doctors and drivers to use hexadecimal. But at least it makes unit conversions as trivial as base-10 metric.

Let's say you have your altmetric utopia with prefixes based on powers of 12, regardless of whether you require numbers to be expressed in base-12 or not. What do you do about the rest of the world which uses base-10?

You're the head chef for a cruise ship, and the upcoming voyage has 572 people for 14 days. (Imaginary) guidelines say that to keep people happy, you need to provision an average of 800 g of food per person per day. In metric: 572×14×800 g = 6406400 g ≈ 6406 kg ≈ 6.4 Mg (tonne), a simple calculation.

In altmetric, you still get 6406400 g, but now you need to start dividing by 12 repeatedly to form larger groups. Let's just say alpha = 12^3 and beta = 12^6. So 6406400 g ≈ 3707 alphagrams ≈ 2.15 betagrams. That doesn't make life any easier.

Or let's take a somewhat different example. When buying stocks on the market, you specify how many shares you want to buy and the price you want to buy at. But you can't say "I have $X, buy as many shares as possible without exceeding $X". So say you just received a $30000 bonus (after tax) and your favorite stock has an asking price of $68.49 per share for an unlimited quantity. In decimal math, this is easy to figure out - $30000/($68.49/share) = 438.02 shares, so you round down to 438 shares and place your order.

But suppose you're in some F'd up world where you have to specify your stock order in stones, pounds, and shares ("ounces"), where 1 stone = 14 pounds, 1 pound = 16 shares. So your order of 438 shares becomes 1 stone + 13 pounds + 6 shares. You had to do an excessive amount of busywork just to fit into that non-decimal system. And along the way, you might have to think about things like the fact that it's also $15341.76/stone, $1095.84/pound.

You're not the first person I've come across who wants measurements to be grouped/divided into units by some factor other than 10, usually 12. I did a lot of thinking about this, and my conclusion is that if you make an altmetric system where prefixes are not powers of 10, then you lose a huge benefit of the metric system. (The other huge benefit is coherent derived units, like 1 joule = 1 newton × 1 metre.)

> I take back what I said about the mile.

It looks like the derivation of the English statute mile is this: 1 mile = 8 furlongs, 1 furlong = 10 chains, 1 chain = 4 rods, 1 rod = 5.5 yards, 1 yard = 3 feet. You can confirm that 8 × 10 × 4 × 5.5 × 3 = 5280.

https://en.wikipedia.org/wiki/Mile#Statute , https://en.wikipedia.org/wiki/Furlong , https://en.wikipedia.org/wiki/Chain_(unit) , https://en.wikipedia.org/wiki/Rod_(unit)

everything would still be metric, the calculations would be as simple, every one would learn their baseC times tables and how to do baseC long division.

$3000 / $(68.49/share) = 54.59B1 shares 54 shares = total cost of $2B88.B6 take your remaining 33.07 and have a nice lunch

1000 Cgrams(1728Agrams) = 1kiloCgram 1000kiloCgrams = 1 Cton

but going smaller a third of a Cgram is 0.4 Cgrams a quarter is 0.3 Cgrams

Does this actually makes any ones life better... Probably not. but it has every advantage of using baseA and the minor(very minor) advantage that thirds and quarters are easier.

But this assumes that baseC won over baseA 1500 years ago, and if there is one truly global success story it is baseA, many languages, cultures, writing systems, but everyone(statisticly) uses baseA with arabic style numbers

footnote: I am using the slightly obnoxious prose of using baseA and baseC to avoid the confusing ambiguity that saying base 10 in base twelve means there are twelve numbers in a digit(where the word digit, coming from the way we count on fingers would also mean twelve.)

if a TV seller went bonkers and only said "it's 10:16", can you guess the actual size of that TV?

The singer produces sound pressure waves into a mic. These pressure waves are measured in dB SPL, and the microphone's specifications will tell you its sensitivity, maximum sound pressure level, frequency response, on- and off-axis response, and so on. An engineer can look at all these specs to choose a mic based on the environment, how much background noise there is and where it's coming from, the quality and character of the singer's voice, etc.

The microphone will produce a voltage, which is measured in dBV or dBu. This voltage travels to a preamplifier, which boosts the signal to a nominal level by applying a gain (in dB, with no units since it's just a dimensionless ratio between input level and output level) and converts it to a digital signal -- measured in dBFS ("decibels full-scale", signal level relative to the maximum level that can fit in the bit-width of the digital signal).

Note that all the different signals going into the preamps have wildly different voltage levels -- a kick drum produces much more sound energy than a singer. And the ratio between SPL and voltage is not fixed; different mics have different sensitivities, and an active guitar amp will generate a signal many orders of magnitude stronger than a passive microphone. For some instruments like synthesizers, "SPL" isn't even a concept that makes sense because the sound is produced entirely electronically, rather than by capturing a mechanical wave. So, the preamps are configured to normalize all the incoming signals to one nominal level for processing.

After the preamp, the signal goes through a digital signal processing chain. Most of these processing steps will affect the level of the signal, and the amount is measured in dB (without units, since this is a dimensionless ratio between input level and output level. Remember, we're dealing with a fully digital waveform, so there is not even a physical measure of "loudness" or "signal strength" that can apply to the signal at this point.)

The signals from all the different sound sources are mixed together, and the mixer's per-channel volume faders are marked in decibels -- usually from +10 to -infinity, with 0 corresponding to "unity gain" (which means the output signal should have the same intensity as the input signal). Again, no units because we aren't measuring a physical quantity, just how much the mixer should change the intensity of the signal.

Finally, the signal is converted back to an analog voltage (measured in dBu) and sent to a power amplifier. The power amplifier applies an adjustable gain, and outputs a signal measured in watts (dBm) for sending to the PA system. You might then walk around the room with an SPL meter to ensure the sound is at a safe level; the value you measure will depend on the frequency and directional response of the speakers, as well as how far away from the speaker you're measuring.

Throughout this process we had signals in the form of sound pressure, voltage, digital samples, and wattage, at power levels ranging from microwatts to kilowatts. Even a simple physical quantity like sound pressure for a single signal is not straightforward -- how far are you measuring it from, and are you talking about SPL before the microphone or after the speaker?

The fact that a single unit is used for all of these different purposes is a feature, not a bug. If my preamp is close to clipping and I turn it down by 3 dB, how much do I need to turn up the gain at my compressor to compensate? Easy -- 3 dB. If we used more "appropriate" physical units at each step of the signal chain, it would be impossible to determine this number quickly or in your head; and would involve taking into account even more factors I haven't mentioned (like input impedances). The fact that decibels are scaled differently depending on whether you're working with voltage or power means that 1 dB corresponds to the same change in loudness everywhere without having to remember whether it's 1 dB of voltage or power.

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?

If decibels were used only to measure sound relative to "experienced loudness" there would be no complaint.

The complaint is that it is used in many other ways, often without distinguishing what the base unit is.

No need for an encoder and software, though, logarithmic pots are readily available for precisely this reason. :)

Ears can register sounds from maybe 20-30 dB upwards of 120ish which isn't a factor of 4-6 in terms of power but rather a factor of 120-30=90 decibels or 9 bels or 10^9 or one billion.

Because your ears have absolutely enormous range you need the potentiometer (pot) to have a logarithmic taper to it. The amplifier has an essentially fixed amount of amplification so that's a fixed sound dB output. Your ears can hear a vast range. A linear pot essentially locks the entire output into the same 10 decibels as the amplifier maximum output through its linearity. Once you've turned it to 10% of the range it has precisely 10 decibels worth of range left. If you want to turn the volume down by 40 decibels you have to do that within the 0-10% part of the pot's range.

A logarithmic pot will give you maybe 40-60 decibels worth of adjustment by dividing things up differently. Every 20% of the range increases the output not by 20% but by a factor of 10 let's say. That gives you a pot with a range of 50 decibels which is enough that it roughly matches the absolutely miraculous range of the ear.

You need a knob that increases power exponentially to hear a linear increase in loudness.

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).

Try going into Android "Developer options" and enable the option "Disable Absolute Volume". Some devices cannot handle the way Android maps the "master" volume of the system to Bluetooth. With the option enabled you will have a separate slider to adjust the Bluetooth volume, and the volume buttons will instead only control the "Media" volume.

An alternate thing to do is under the same Developer Options is instead of disabling Absolute control is to change the Bluetooth AVRCP version to at least v1.5. v1.5 AVRCP introduces the Absolute Volume control functionality.

But, it could also be what you may have are Bluetooth devices that do not support Absolute Volume, or lack AVRCP v1.5 compatibility. If none of this works, I suggest purchasing the "Precise Volume 2.0 + Equalizer" app. I use this as it gives you more fine-grained control over the number of steps in the volume slider (for example, I now have 100 steps). It also allows you to calibrate the number of steps to a specific device, so you can literally change how many steps from quiet to loud. It's worth all of the $10 it costs, and has other nice quality of life features as well.

To me it seems like one of two things: external pressure between hot and cold is mismatched so a small change to one side overwhelms the weaker flow.

Alternatively it might just be a broken or poor quality mixer that isn’t providing the appropriate ‘nuance’ of control, and that may indeed be expressed as some sort of non-linear relationship.

I know you mean legionnaires' disease, but the idea of a bunch of soldiers getting to your house because you turned your boiler too low made me chuckle. Good thing the US have the third amendment to protect against this.

... hot water baths ..."

It also a simple thing to check and would be the first step in my troubleshooting routine for this complaint.

Here is a link describing the dangers.

https://www.heatgeek.com/hot-water-temperature-scalding-and-...

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.

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.

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

OP isn't criticizing logarithmic scale in general but dB in particular.

If dB in particular aligned well with human experience - volume knobs would be labeled with dB values instead of 1-11.

People in the field get this wrong all the time — for instance, the volume control on ChromeOS appears to be a linear multiplier, yielding a control with huge perceived steps in the output between 0 and 3, and negligible perceived change in the output between 7 and 10.

I suspect that the confusing design of the dB contributes towards how often such mistakes get made.

This also doesn’t even begin to touch on frequency response curves.