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Macca
01-02-2014, 13:12
I believe there should be some codification as to what units of measurement we use, just to establish a standard. The following is an attempt to do that relying on commonly used and best practice within the hobby:

Turntables: All measurements should be in grams (tracking weight, anti skate etc) and millimetres. Except for arm lengths and record widths which shall be in inches

Speakers: volume in litres, weight in kilos but dimensions of cabs and width of drivers in inches. Note driver parameters (cone excursion etc are always to be given in metric)

Tape: Tape speed should always be quoted in inches per second. For all other parameters use metric

Rooms: Dimensions should be given in feet and inches but it is permissible to additionally quote in metres and centimetres.

Temperature: if low quote in Centigrade, if high use Farenheit.

Distances: Feet and yards or if longer English Miles. You may quote kilometers additionally if you so wish

In the case of larger measurements:

Height: to be expressed in double decker buses, or for very high, use Eifel towers.

Area: In Football Pitches

Length: in double decker buses laid end to end

Long distances: in fractions or multiples of the distance from here to the Moon

Volume (of a liquid) Olympic Swimming Pools

Volume (of a gas) Albert Halls

Money: to be quoted in fractions or multiples of the amount stolen in The Great Train Robbery.

Hopefully this will allay any confusion moving forward.

John
01-02-2014, 13:15
lol

The Grand Wazoo
01-02-2014, 13:28
All very good and as it should be. However, you appear to have missed the unit of measurement for large areas: Wales

Macca
01-02-2014, 13:33
All very good and as it should be. However, you appear to have missed the unit of measurement for large areas: Wales

Well pointed out. Without the Wales unit we would be stuck when it came to large areas. However for our transatlantic cousins the 'Texas' is also acceptable in this regard.

MartinT
01-02-2014, 14:29
As in... my room is a 1/4 Wales. have I used that correctly?

Macca
01-02-2014, 14:36
No - that's like expressing tracking weight in African elephants or family cars.

MartinT
01-02-2014, 14:44
Ah ok, I'll stick to 4 x 10¹² square angstroms as I always quote it.

walpurgis
01-02-2014, 16:52
Is a 'gnats whisker' a 'touch' smaller than a 'smidgen' and how does a 'tad' relate to these? :D

synsei
01-02-2014, 17:07
If absolute accuracy is required the 'there or there abouts (ToTA)' is essential :D

Effem
01-02-2014, 20:43
Look fellas, 9 inches is still 9 inches, none of this foreign Willymetre stuff on this forum thank you :eyebrows:

walpurgis
01-02-2014, 21:11
Look fellas, 9 inches is still 9 inches, none of this foreign Willymetre stuff on this forum thank you :eyebrows:

Well, I suppose if a mere 9 inches is what you're lumbered with..............

Andrei
01-02-2014, 21:33
All very good and as it should be. However, you appear to have missed the unit of measurement for large areas: Wales
When I was in South Africa they liked to point out that the Kruger Game Park was the same area as Wales. Not sure if that meant to indicates largeness or smallness though.

Macca
01-02-2014, 21:38
Lots of things are the size of Wales. That is why it is such a good unit to use. Examples include the area of rainforest destroyed every year and the area covered by the floods in Australia last year. Quite remarkable when you think about it.

The Grand Wazoo
01-02-2014, 22:36
Of course we shouldn't forget that this is not to be confused with the similarly named but vastly smaller Icelandic unit. Whales are, as we all know, very much smaller than Wales. Smaller, in fact than football pitches.
A simple mistake to make, but disastrous if you're planning world domination in any field of endeavour!

StanleyB
01-02-2014, 22:40
Not every AoS member is living in a former or present British Empire colony or protectorate. So inches and feet won't be units of measures used for room or cabinet sizes. So stipulating them as a requirement could be an issue.

The Grand Wazoo
01-02-2014, 22:44
Well they'll just have to knuckle down and learn the standard then Stan.
I don't know, the impertinence of it! Johnny Foreigner'll be expecting us to learn all of his languages next!

We're going metric inch by inch and don't you forget it.

Macca
01-02-2014, 22:53
Yes. The exotic mixture of metric, Imperial, Albert Halls and Wales has stood the test of time and should be adopted by all nations.

There is no doubt that when mankind leaves the solar system he will continue to encounter phenomona the size of Wales or the height of 3 Eifel Towers. So best to prepare now.

walpurgis
01-02-2014, 23:00
Well they'll just have to knuckle down and learn the standard then Stan.
I don't know, the impertinence of it! Johnny Foreigner'll be expecting us to learn all of his languages next!

We're going metric inch by inch and don't you forget it.

Damn right! I think re-imperialisation is the only way forward. We could go back to buying cars in Guineas and paying 'two and twelve pence halfpenny' for a bag of gob stoppers. Petrol could then go back to being 7/6d per gallon.

Funny how we get led by the nose by the yanks, but unlike them, who have (largely) stuck resolutely to feet and inches, etc., we had to be bullied into (supposedly) accepting metric. It was a disgrace when our shopkeepers were prosecuted just for offering buyers the option to buy by the pound as well as the mandatory kilo. I bet the 'jobsworths' were filled with glee at that move.

Effem
01-02-2014, 23:05
I went into a greengrocers and asked for five pounds of spuds. The shop assistant said "Sorry it's Kilos now" so I replied "OK, I'll have five pounds of kilos instead please".

NOSENSAYUMA

MartinT
02-02-2014, 18:28
Heh, heh. I think it's high time we penalise the mentioning of imperial units by public flogging. That'll stop people giving me their weight in stones. What a very silly measurement!

synsei
02-02-2014, 18:44
Then there was that NASA Mars probe which failed due to half the craft being built to metric standards and t'other half imperial, you couldn't make it up... :lol:

Macca
02-02-2014, 19:30
Then there was that NASA Mars probe which failed due to half the craft being built to metric standards and t'other half imperial, you couldn't make it up... :lol:

I thought that story was true as well but a very sciency pal was telling me that it is an urban myth?

Andrei
02-02-2014, 20:16
It can't be, there are are no urban areas on Mars. That's right, isn't it Dave?

Barry
02-02-2014, 20:45
Ah ok, I'll stick to 4 x 10¹² square angstroms as I always quote it.

That's a square of side 0.1mm. How tall are you Martin?

Barry
02-02-2014, 20:50
Yes. The exotic mixture of metric, Imperial, Albert Halls and Wales has stood the test of time and should be adopted by all nations.

There is no doubt that when mankind leaves the solar system he will continue to encounter phenomona the size of Wales or the height of 3 Eifel Towers. So best to prepare now.

OK, so my amplifiers have a power of 16,050 BThU/fortnight per channel. And my listening room measures 2rods in length x 1.8cubit in width x 24hand in height.

MartinT
02-02-2014, 21:37
That's a square of side 0.1mm. How tall are you Martin?

Damn, and I was so careful with the calculator! :lol:

Joe
03-02-2014, 12:06
I thought that story was true as well but a very sciency pal was telling me that it is an urban myth?

Urban myth AFAIK, but NASA made some elementary statistical mistakes which led to the space shuttle disaster. The story about the model of Stonehenge in Spinal Tap, is, by contrast, perfectly true.

Joe
03-02-2014, 12:11
Not every AoS member is living in a former or present British Empire colony or protectorate.

Well they damn well should be!

Joe
03-02-2014, 12:12
Then there's the fine old British measurement of excess, the firkin, as in 'Two firkin heavy'.

StanleyB
04-02-2014, 23:20
I thought that story was true as well but a very sciency pal was telling me that it is an urban myth?
It actually happened on two occasions. One case was with one of the lenses on the Hubble telescope. The other was with the NASA Mars Orbiter. They managed to fix the Hubble's fault by fitting a correction lens. But the NASA Mars Orbiter had long crashed before they figured out why. The actual date that it happened was on the 23rd of September 1999.
So your sciency pal knows far less than you respect him for.

The Grand Wazoo
04-02-2014, 23:26
I remember reading somewhere when I was a teenager that there is at least one recorded instance of a scientific body rounding pi to 4!

StanleyB
04-02-2014, 23:46
I remember reading somewhere when I was a teenager that there is at least one recorded instance of a scientific body rounding pi to 4!

http://i254.photobucket.com/albums/hh116/balthamossa2b/1290457745312.jpg

The Grand Wazoo
04-02-2014, 23:58
Nay, nay and thrice 3.141592653589793238462643383279502884197169399375 1058209... times nay.
Stanley, you are a bad, bad man!

MartinT
05-02-2014, 07:16
One case was with one of the lenses on the Hubble telescope.

I thought it was the main mirror itself, an astonishing error?

dave2010
05-02-2014, 10:01
Damn right! I think re-imperialisation is the only way forward. We could go back to buying cars in Guineas and paying 'two and twelve pence halfpenny' for a bag of gob stoppers. Petrol could then go back to being 7/6d per gallon.
I don't think petrol ever did get to 7/6d per gallon - except perhaps under extreme circumstances and maybe a black market. The last pre-decimal price I remember was about 3/6d.

Barry
05-02-2014, 16:45
http://i254.photobucket.com/albums/hh116/balthamossa2b/1290457745312.jpg

The error in the argument occurs after step 4: with the second and subsequent corners removed, the stepped perimeter ceases to touch the circle at all points. If this process is repeated infinitely, one achieves a non-circular shape having a perimeter larger than the circle (i.e 4), but only touches the circle at the four points shown in step 3.

Barry
05-02-2014, 23:37
After due consideration (whilst in the pub and after a few pints of beer), I realise I was incorrect in my dismissal of Stan’s quoted ‘proof’ that π = 4.

I claimed that subsequent removal of the corners of the enclosing square would, if carried on infinitely, create an enclosing perimeter that would only touch the circle in 4 places. I was wrong, on two counts. First it would contact the enclosed circle at eight points and, more importantly, the ‘proof’ actually assumed subsequent corner removal could be rectangular in shape rather than square (and therefore could contact the circle at an indefinite number of points).

Even so, the fallacy of the ‘proof’ is one of confusing, or assuming, that the enclosing perimeter would, in the limit, coincide with the circumference of the enclosed circle. The fallacy is that the enclosing perimeter, being made up of many elemental triangles, confuses the hypotenuse of such triangular elements as being the same as the sum of the other two sides; and that in the limit as the size of the triangle becomes vanishing small, this error becomes negligible.

It does not; the sum of the sides of a right angle triangle is always greater than its hypotenuse, regardless of the size of a triangle. So in the limit the enclosing perimeter so formed will always be greater than the circumference of the enclosed circle.

The Grand Wazoo
05-02-2014, 23:43
Indeed. If continued to the conclusion that's suggested, each error in itself is tiny. But as there are an infinite number of them, they add up to the same error as the first one.
No matter how close each outer point is to the circumference, it will never touch it.

The whole thing is a load of loblocks.
As I said, Mr Beresford is a bad, bad man!

Reffc
06-02-2014, 10:31
How should we go about defining drift of components? For large variations (ie voicecoils that get heated up) could we refer to the drift as being "continental"?

For small areas of drift with time, should this be referred to as a "slip" and if making the components just out of tolerance, is this then an "oops"?

Naughty Nigel
26-03-2014, 15:40
I don't think petrol ever did get to 7/6d per gallon - except perhaps under extreme circumstances and maybe a black market. The last pre-decimal price I remember was about 3/6d.

When my dad got our first car, a Vauxhall Victor, petrol was £1 for four gallons, or in other words, 5/- per gallon! That is 5.5 pence per litre in modern parlance!

Where, when and why did it all go so wrong? :(

Nigel.