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The Divide
22-04-2004, 01:37 PM
Exactly how many cyclic revolutions takes place in 1Hz

I undertstand that 1khz is equil to 1000hz

So whats 1hz, is it just one revolution or is it representing something like 100 revolutions?

I know this is way beyond the frequency repesonse of music systems, just curious.

The Divide
22-04-2004, 01:42 PM
Ohh I got it...

hertz ( P ) Pronunciation Key (hûrts)
n. pl. hertz Abbr. Hz
A unit of frequency equal to one cycle per second. See table at measurement.

My appologies :oops:

Chris Hare
22-04-2004, 02:22 PM
just got your new composure mr fernando... lovely piece mate.. MORE PLEASE :clap: :shock:

The Divide
22-04-2004, 02:23 PM
Back again. :lol:

Question...

If 1 millisecond is equal to .0001 seconds Ie a thousandth of a second then why is it called a millisecond???

Should it be called a thousecond :lol: Have I got this wrong or am I getting confused over nothing?

Trying to work this out....

Yamaha SPX90 FX processor...

It has a freeze function which records 2000.0 milliseconds

Which is basically, if I am right 2 seconds?

How many samples are captured and how much memory is used up when recording at 31.25 kHz @ 16bits

I am guessing its 31.25 X 2 = Samples captured

Because 31.25 kHz is the amount of samples captured per second and we got 2 seconds there.

How I work out how much memory that amount takes up is beyond me

Is it something like 31.25khz X 16 = totall amount of memory used?

Can anyone help me?? It looks complicated but I think its probably simple when you know.

Anyone....

:lol:
Pretty please :lol:

The Divide
22-04-2004, 02:25 PM
just got your new composure mr fernando... lovely piece mate.. MORE PLEASE :clap: :shock:

Ohhh hahaha ta man, but ime not bothered about that right now !!! :lol:

This questions doing my head in
:neutral:


:lol:

Chris Hare
22-04-2004, 02:35 PM
unfortunatley i cant help you there... thats beyond my knowledge... :roll:

keep at it mate .. try to slip into the gap between thoughts and maybe it will come to you... ;)

gumpy green
22-04-2004, 02:38 PM
Back again. :lol:

Question...

If 1 millisecond is equal to .0001 seconds Ie a thousandth of a second then why is it called a millisecond???

Should it be called a thousecond :lol: Have I got this wrong or am I getting confused over nothing?

Trying to work this out....

Yamaha SPX90 FX processor...

It has a freeze function which records 2000.0 milliseconds

Which is basically, if I am right 2 seconds?

How many samples are captured and how much memory is used up when recording at 31.25 kHz @ 16bits

I am guessing its 31.25 X 2 = Samples captured

Because 31.25 kHz is the amount of samples captured per second and we got 2 seconds there.

How I work out how much memory that amount takes up is beyond me

Is it something like 31.25khz X 16 = totall amount of memory used?

Can anyone help me?? It looks complicated but I think its probably simple when you know.

Anyone....

:lol:
Pretty please :lol:


a milli second is 1000th of a second

check this for all your prefixes

http://www.simetric.co.uk/siprefix.htm

"Note: A very common mistake is that the prefix milli- stands for a millionth.
WRONG!!
As can be seen from the table above, milli stands for a thousandth. It comes from the French, mille for 1000 - they could not use it for the 1000 prefix as that was bagged by the Greek word, kilo"

The Divide
22-04-2004, 02:42 PM
http://www.simetric.co.uk/siprefix.htm

"Note: A very common mistake is that the prefix milli- stands for a millionth.
WRONG!!
As can be seen from the table above, milli stands for a thousandth. It comes from the French, mille for 1000 - they could not use it for the 1000 prefix as that was bagged by the Greek word, kilo"

Perfect :) Thanks!!! That links going to come in handy

So I just need to take 2 x 31.25 = 62.5 samples and somehow work out how much memory that takes up

62.5 X 16 = 1000kb I think

1 megabyte

Foook it that will do

detfella
22-04-2004, 02:55 PM
1 hz is 1 cycle per second and 1000 hz is a thousand cycles per second.

1 millisecond is like saying a thousandth of a second. "milli" is the prefix added to "second" and abbreviated as ms. The milli bit says that its a thousandth. So you were right, just those damn confusing SI terms.

So for 31.25 kHz u can record about

frequency is cycles per second, so if u divide by the time period, u get number of samples:

312500/2 = 156250 samples

The bitrate refers to the how many bits (those damn 1's and 0's) are used each second. To work that out, you've gotta multiply the sampling rate, with the resolution (16 bits) and the number of channels (stereo = 2, mono = 1). The bit rate can be used to work out how the memory usage.

check this loveely web resource

http://www.softsynth.com/musiclinks.html

(THIS IS NOT GOSPEL) :nono:

The Divide
22-04-2004, 03:00 PM
:lol: :nono: :lol:

R X FS divide by 8 (bytes)

R = 16
FS=sampling rate

16x31.25= 500 (per second)

500 X 2 (seconds) = 1000

1000 divide by 8 = 125 bytes (mono) :lol:

Done, thanks man!!

DJZeMig_L
22-04-2004, 06:06 PM
PS ... 1 milis. = 0,001 not 0,0001! :doh: :rambo:

Z

Jimfish
22-04-2004, 09:17 PM
what the f*cks goin on here??

my brain hurts!

dirty_bass
22-04-2004, 11:56 PM
numbers!!!!!! :shock:

dirty_bass
22-04-2004, 11:58 PM
tHey onLY lET mE uSe cRayOns if I pRomiSE nOT TO BITe

The Divide
23-04-2004, 12:09 AM
tHey onLY lET mE uSe cRayOns if I pRomiSE nOT TO BITe


:lol: :lol: Hahaha

Antinoise
23-04-2004, 01:07 AM
Does any of this relate to me shakin my ass?

The Divide
23-04-2004, 01:24 AM
Not unless your planning on recording it onto a sampler and your running out of memory :lol:

Ritzi Lee
23-04-2004, 08:04 AM
It's just a simple formula.

If
T = cycling time in seconds,
f = frequency in Hz, then

f = 1 / T



And a wave function can be characterised as a superposition of standard sinus wave functions of the form:

x(t) = A sin (2 Pi f t)

where A is the amplitude,
Pi = 3.1415926535897932384626433832795.....
f = frequency
t = time (dynamical variable)

Sometimes it's convenient to write the sinus in the form

A sin (2 Pi t / T) or A cos (Pi - 2 Pi f t)....



:twisted:

Barely Human
23-04-2004, 10:22 AM
:shock: My head hurts!

Can we talk about Moores Law now :lol:

yorkie
25-04-2004, 11:57 AM
Students...! :roll:


I remember doing these questions for Paul Conway as well!! :clap: :clap: :clap:

The Divide
25-04-2004, 04:13 PM
Students...! :roll:


I remember doing these questions for Paul Conway as well!! :clap: :clap: :clap:



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thorin
26-04-2004, 12:48 AM
ph ar, 1Kb = 1024Bytes NOT 1000 Bytes :)

its 2^10 or somthing, always 2 to the power of somethin..

yorkie
26-04-2004, 11:12 AM
:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:


WOT A LEGEND!!!


:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:

The Divide
13-05-2004, 10:15 PM
I got another one, its been blaggin my head...

Say i have an arc on a surface and I need to find its distance from one end to another. My arc distance will be called X

I also have a radius which is 12.5

X= 2 PI x R = ??? / 8 (45deg)
X= 6.28 x 12.5= 78.53/8 = 9.81

Now I know thats the correct measurement for X..

But there’s a problem with this method, what if the angle has to be different to 45 degrees. Is going to screw the formula up because I won’t be able to divide it by 8

So the correct formula is....

angle x 2PI Radius = Answer in radians? which is divided by 360

X = 45 x 2 x PI x 12.5 = 3534.29 / 360 = 9.8174

But this formula is used because? i cant word it. Is it something to do with radians and degree's. The 2nd formula works because its not working it out using radians and just degree's? :neutral: :neutral: My head hurts

The Overfiend
13-05-2004, 11:15 PM
Remember in scanners when the guys head exploded?

That's me when I read through half of your question Fern.

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