frequency as to notes

  • Thread starter Thread starter Setherial
  • Start date Start date
I created a chart for all equal tempered western scale notes in the audible range. It supports changing the frequency of the base note, for example if you should need the Hz if A=443. I wasn't able to attach ti due to file format limitations but drop me a line and I'll e-mail it to you.

/Ola
 
yeah I know....DK...but...

If a difference in frequency makes for a different sound (ie A 440 not = to A443) then in theory as you said it is possible. BTW I was being a BIT facetious with my post. I've studied music some 30 years.

Just trying to expand the mind by applying mathematical principals...

Yes - I know I'm full of SHITE..... ;)

peace, zip >>
 
Yes, Zip, there are an infinite number of freqs between any two notes. Which is why I shy away from digital recording. Digital cannot represent an infinite number of units between any two points. It is discrete. Analog circuits, on the other hand, can. Though I suspect that when you get down to the sub atomic level, it's all discrete anyway.

Correct me if I'm wrong, but a freq is represented on magnetic tape as a change in signal amplitude as the tape moves across the head. The faster the change, the higher the freq. Because the medium is continuious in both directions (amplitude and length), you should be able to represent any freq.

Digital, however, represents a freq as a series of bits, and there will be a point where there cannot exist a freq between two. For instance, there is nothing between freq 11111110 and 11111111 (8 bit system).

As DK said, we wouldn't be able to tell the difference, so unless your a strange sort like myself, it doesn't matter.

Any takers?

Ziller
 
Bits aren't frequencies. Digital is able to represent any frequency below half the sampling rate. You are right that it's discrete though, and you are also correct about analog being discrete too, on a quantum level. However, with a 24/96 digital system, these discrete levels are much closer than human hearing can discern, and hence it is not an issue.

(Although I'm quite sure that if 64/192 systems arrive someday in the future, people will claim that the difference is huge and obvious too... ;) )
 
Right. I ment that freqs are *represented* as a series of bits. For instance, A 440 may be represented as 110101100010101101011110 on a 24 bit system. The D/A converter would convert that to an analog signal to send to analog circuits, such as speakers, when needed.

Conversly, an A/D conversion may end up rounding up or down to the nearest representable bit pattern, thereby not exactly representing what is being input.

Wait a minute. I think I've got it wrong. I'll leave the above up there in case others interested. So, what is represented by the bits is the *amplitude* of the input signal (or the sample), not the freq? The sampling rate being equivelent to tape moving across the heads of an analog system, and the bit pattern being the amplitude of the signal? In that case, you are limited in both directions. You certainly can't sample an infinite number of time, nor can you represent the exact amplitude of a signal, unless the amp happens to be some small, non-repeating value.

????
 
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>For instance, A 440 may be represented as 110101100010101101011110 on a 24 bit system.
>So, what is represented by the bits is the *amplitude* of the input signal (or the sample), not the freq?

Right- the frequency can't be represented by a single sample no matter how many bits you throw at the problem.

So on the face of it: digital is an annoying approximation to real sound akin to trying to construct one of those avatars with the 60 x 60 pixel limitation. Not much photo-realism there, eh? But in reality even 16/44.1 does the job. Sure- I've heard vinyl recordings (sorry if you youngn's equate those with wax cylinders :) ) that sound better than the same recording on CD but not many people have the bucks to invest in a turntable/arm/cartridge combo that can extract this sound from the disc. Plus each play ruins the medium permanently just a little bit and that sucks most of all. And who would argue that CDs sound better than 2" tape? But where are you gonna find your favorite commercial music on 2" tape? And how many people even have access to someone else with a 2" tape player?
 
Originally posted by Ziller
Wait a minute. I think I've got it wrong.

Yup. :)

I'll leave the above up there in case others interested. So, what is represented by the bits is the *amplitude* of the input signal (or the sample), not the freq? The sampling rate being equivelent to tape moving across the heads of an analog system, and the bit pattern being the amplitude of the signal?

Bingo! Now you got it right!
 
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