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The grid on a spectrum analyzer
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| Secret Water |
I have always wondered what the grid for on a spectrum analyzer is for....it corresponds to the frequencies which seem to increase exponentially. Why do the frequencies seems to grow at a 2:1 rate or ratio?? Anyone know?? thanks
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| Acton |
| That's because it's a logarithmic scale, it's a common mathematical technique used when a large number of values need to be represented. |
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| evo8 |
| quote: | Originally posted by Secret Water
I have always wondered what the grid for on a spectrum analyzer is for....it corresponds to the frequencies which seem to increase exponentially. Why do the frequencies seems to grow at a 2:1 rate or ratio?? Anyone know?? thanks
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its because the graph is logarithmic on the X axis |
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| Secret Water |
| so basically to save space because it wouldn't fit horizontally on the screen?? makes sense... |
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| evo8 |
| quote: | Originally posted by Secret Water
so basically to save space because it wouldn't fit horizontally on the screen?? makes sense... |
yeah kinda - i think its because the amplitudes at higher frequencies dont carry the same weighting as frequencies say below 1k
someone else will come along and explain this properly :o |
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| Secret Water |
| ya but this exponential curve happens 3 times on the spectrum....so I doubt it "highs"..... |
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| Looney4Clooney |
pitches are ratios. When the science came about, it only made sense to represent ratios instead of linear relationships.
A____A+__ A++_ Richie _____________/// index
440 880 1760 3520_________/ using multiples
A____A+__RANN___A++
440 880 1320 1760 linear
there is an actual biological reason these ratios are how they are but not really important
same goes for mixer feedback. Notice how the the first 12dBfs take up most of the room. |
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| Secret Water |
| Duh....i totally didn't realize its the mhz in-between the labelled ones that are not written like.............20 (Written), 30, 40, 50, 60, 70, 80, 90 100 (written) and it just goes all the way across... |
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| DJ RANN |
| quote: | Originally posted by Looney4Clooney
pitches are ratios. When the science came about, it only made sense to represent ratios instead of linear relationships.
A____A+__ A++_ Richie _____________/// index
440 880 1760 3520_________/ using multiples
A____A+__RANN___A++
440 880 1320 1760 linear
there is an actual biological reason these ratios are how they are but not really important
same goes for mixer feedback. Notice how the the first 12dBfs take up most of the room. |
I just wanted to say thank you for correctly denoting me as linear.
the history of biological tuning and 440 is really interesting, and it was only actually in 1939 when it was universally adopted and recognized as the standard for equal temperament. It was as low as the mid 300s in the 17th century. |
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| Looney4Clooney |
| actually i assumed you A ++which is a frequeny known for being just not wanted . I am A+++ . Sort of fused knowledge and insult in one package with ty formatting. I need to work on my delivery. |
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