Need To Borrow A Decibel Meter

[simon43]

I'm looking to build another guesthouse near to the airport, and I've found a plot of land with potential for this business. However, it lies closer to the runway than my existing hotel and so the plane noise is higher.

I can construct a guesthouse with soundproofing, but it would be useful to measure the typical sound levels at that location when a plane takes off (and lands).

Does anyone have a sound level/decibel meter that I can borrow for a few hours??

Thanks

Simon

[katasyd]

Only seen one here in Phuket and it was at the DLT in Phuket town.

Maybe they will rent it to you.

[welbymd]

DB meters are fairly inexpensive. $200 will buy you a decent meter. If you can afford a plot of land and build a hotel, whats a few dollars for a meter. Then you can use it to measure sound levels if the guests make too much noise.

[Phil Conners]

If you already have an Android phone you can download a DB meter as a free app for it - http://www.appbrain.com/app/decibel/bz.bsb.decibel

[katasyd]

If you already have an Android phone you can download a DB meter as a free app for it - http://www.appbrain..../bz.bsb.decibel

Great idea.

Just checked the itunes store and they have numerous decibel meters for the iphone too.

[simon43]

Katasyd and Philconnors - what a great idea, thanks! I have an iphone, so will check out the App Store.

As to being able to splash out $200 on a sound meter, that's not an immediate assumption. I have no lump sum of money to buy land or build a guesthouse. But, based on my track-record of 3 profitable hotels/hostels (airport hotel for 6 years, Ao Nang guesthouse for 9 months, another airport guesthouse for 2 months), the Thai bank is supporting our project and so I'm hopeful of getting their OK on all this.

Simon

[Jimi007]

I would say that those mobile app meters are not really working. It is likely possible to spot the difference between now and then (when the walls are there), but to get reliable readings - I don't think so.

Microphones on mobile phones is pretty small (and cheap as it could possible be to provide decent sound quality). Mobiles also have all kind of hardware/software filters to reduce the background voices.

He's not using it for a legal case. It will give a good approximation. I have one on my iPod touch and it's in the ballpark. iPhones aren't cheap and have okay microphones as they are used for "HD" video recording, at least the 4's. I have been a live sound engineer for over 30 years, so I can pretty much guess what the level is without a meter. I also have an analog old db meter, but it's in California. I'll have to compare the two when I'm there. But there are two or more weighting scales on most "real" meters: A and C normally. A is what is used for legal sound limits usually. See: http://en.wikipedia.org/wiki/A-weighting

It explains the whole thing.

[Jimi007]

He's not using it for a legal case. It will give a good approximation. I have one on my iPod touch and it's in the ballpark. iPhones aren't cheap and have okay microphones as they are used for "HD" video recording, at least the 4's. I have been a live sound engineer for over 30 years, so I can pretty much guess what the level is without a meter. I also have an analog old db meter, but it's in California. I'll have to compare the two when I'm there. But there are two or more weighting scales on most "real" meters: A and C normally. A is what is used for legal sound limits usually. See: http://en.wikipedia....iki/A-weighting

It explains the whole thing.

That Wikipedia article was too far from my knowledge to comprehend it well . My background is in mobile industry. If an mobile manufacturer is going to buy an patch of 1-50 million microphones, they are likely to buy the one which is 1 cent cheaper, even if can not collect all the frequencies, specially the ones which would anyway be cut out when using narrow band voice encoding. Some of the phones do support wide band (for calls), but not all. i4 could do that, but not necessarily.

Add to this the limitations of the phone operating system and the limitations of the application developer. I would not plan expensive sound proofing based on that data.

Microphone should be easy to test by recording high frequency sound like crickets with the mobile phone and then play it back.

When calling to someone, the sound should not get trough, except using Skype on the laptop (which is using wide band codecs).

Then again. As you know, human perception of the noises vary depending of what kind of noise we are dealing with. This was mentioned on the wiki article as well. If the noise consist of different frequencies and amplitudes (volumes?), ear gets irritated. Best example of this is when making the 'screek' sound with dry nails on blackboard. I'm in impression that the noise from the jet engines are slightly similar (although lower frequencies) as the nails on blackboard.

Anyway. I think the best option for the OP would be that someone who really understands the matter, like you, would get to the site and do the sound analysis. Then give some advice how to plan the sound proof with trees, walls etc. in to comfortable level.

It would be great to hear the output of the comparison between real db meter and the iphone application. I wouldn't mind being wrong on this.

-Pekka

I found the specifications for the iPhone 4. It doesn't say what the microphone's frequency response is. A db spl meter microphone isn't used for recording, so I doubt they are that wide of a bandwidth. We use calibrated microphones to do a computer analysis of a room to EQ and set delay times. They aren't the same at all as the type we use for recording and amplification of sound. I started doing sound before we had laptop computers and analysis programs and I can tune a room by ear, well within computer program specs. The iPhone has pretty high video quality, 720p/30 fps and audio playback is 20Hz to 20K Hz, so I would think the microphone would be okay. See all specs here: http://www.apple.com/iphone/specs.html Anyway, it's better than nothing...

[Jimi007]

This program seems to be rather professional and you can buy an interface to use a real calibrated microphone on your iPhone or iPod Touch. I might have to look into this a bit more. See link: http://studiosixdigital.com/

[simon43]

As has been said, this is not required for a legal case. I just want to 'get a feel' for the noise level in dB as the planes take off. I downloaded an iPhone sound meter app and that seems to be indicating the correct dB levels for eg, normal conversation, quiet room etc.

In any case, if the bank agrees to this project, then I should construct the building with sound-proofing in mind - to enable guests to get a good night's sleep!

Simon

[Semper]

Katasyd and Philconnors - what a great idea, thanks! I have an iphone, so will check out the App Store.

As to being able to splash out $200 on a sound meter, that's not an immediate assumption. I have no lump sum of money to buy land or build a guesthouse. But, based on my track-record of 3 profitable hotels/hostels (airport hotel for 6 years, Ao Nang guesthouse for 9 months, another airport guesthouse for 2 months), the Thai bank is supporting our project and so I'm hopeful of getting their OK on all this.

Simon

How much was the iphone?

[simon43]

How much was the iphone?

It came free with my last software contract

Simon