One-Third Octave - Lower Bands Standard Frequencies 2

[271828]

Sorry for the silly question, but here goes!

I need the lower, center, and upper frequencies for the one-third octave bands below 4 Hz. The references that are low-hanging fruit (like

https://onlinelibrary.wiley.com/doi/pdf/10.1002/9781119038122.app3)

start at higher frequencies.

I had this info at one time but am struggling mightily to put my finger on it again.

If someone would send a reference or list for these, I would much appreciate it.

 

[GregLocock]

The frequecies are always a ratio of .5 below the equivalent one octave above. Or if you prefer 2^(-n/6) will step you down, alternating the limit and the centre frequency of each band. In the spirit of pi=3 ASA may have decreed otherwise, but that's the physics of the thing.

Cheers

Greg Locock


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[271828]

Thanks Greg. I don't have a background in acoustics, so I'm not familiar in the calculations you're describing. Do you have a reference that I could use to get up to speed?

 

[GregLocock]

Table C.4 in your ref

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[GregLocock]

I'll quote my solicitor when it comes to that document - never say the same thing twice in different words. In that case they give a mathematical formula, AND they give a table of numbers which are more or less the result of that formula, rounded off. But if the 2nd decimal place was important, which one should be taken?


Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[Strong]

This should keep you busy:
Standard Octave Bands - Noise & Vibration Blog (prosig.com)

https://blog.prosig.com/2006/02/17/...s are 9.84313…Hz and 0.97656…Hz respectively.

Microsoft Word - QRTV-09-05.doc (unece.org)

https://unece.org/fileadmin/DAM/trans/main/wp29/wp29wgs/wp29grsp/QRTV-09-05.pdf

Walt

 

[GregLocock]

Wow. Colin nails it (I knew him a long time ago).

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[271828]

Thanks Strong and Greg. Very helpful.