Low frequencies

Hi there,

Just a quick question, does low frequencies travel further and do they tend to travel through the roof or wall better?

Any advice will be greatly appreciated

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:cop: Three threads merged DEC 21
 
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Galu

Member
2018-04-17 6:50 pm
As a sound waves travel through air, they lose energy and consequently can only travel a limited distance.

Low frequency waves can travel further than high frequency waves because there is less energy transferred to the air.

Hence the use of low frequencies for fog horns.
 

Galu

Member
2018-04-17 6:50 pm
Likewise, LF sound waves pass more easily through a wall than HF as they lose less energy on the way through the wall.

Another factor to consider is diffraction. Because of their longer wavelengths, LF sound waves bend more easily round corners and through openings than HF sound waves. That's a major reason why you can hear the bass frequencies more clearly than the treble frequencies when in an adjoining room or outside the house.
 
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Galu

Member
2018-04-17 6:50 pm
Seriously, you need a gigantic horn!

Here's a photo of my favourite foghorn at the Mull of Galloway, Scotland's most southerly point.

The 'amplifier' is an engine driven compressed air system.
 

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o_O While that is the best amplifier, I have ever seen and wished my wanted one. I just recently posted to another self made form about trying to captive the low frequency with an Microphone – Sound Sensor but needed recommendations. I can't ask on here tho - double posting and such.
 

Galu

Member
2018-04-17 6:50 pm
Thanks Dave!

Oh well I tried! I should have asked Audiobuff88 his budget.

Perhaps the best that can be said is that the mic's performance is reasonable given its low (£30) price.

I guess we need to move into the £500 to £1,000 price range to really hit the lows.

There are some better specified candidates in this Thomann measurement microphone list - any favourites within?

Measurement Microphones – Thomann UK
 

Galu

Member
2018-04-17 6:50 pm
Help me SJ - I am interested in what you mean by "Can you measure very low frequencies in a room accurately?".

Do you simply mean that, because of the undulations in the modal region and the falling sound level below the lowest mode, there is little point in the microphone having a smooth and extended bass response, or am I missing something deeper and more technical?