How can I easily and reliably measure sound (db)

mattyfez · 24 Sep 2013 at 13:41

I read smart phone mics are limited to about 90db,presumably my £2.99 pc mic will be the same? Up to 100db should cover it, any ideas?

Thanks

DJMK4 · 24 Sep 2013 at 13:42

Smart phone mic's / apps would be hugely inaccurate

visibleman · 24 Sep 2013 at 15:44

Sound level meter is your best bet.
A cheapy HK special from an auction site or the electronics 'M' retailer, around £40/50, will give you a (very) rough result. If you're wanting to measure something with any accuracy or to a standard then you're better off hiring a meter (CEL, Norsonic, B&K etc) from the likes of Gracey's or Campbell Associates - prices vary depending on model but you're looking at £10/20 per day.

Unicorn · 24 Sep 2013 at 15:48

Smart phone is crazy inaccurate.. Mine recorded 92.6db from a gas turbine. No chance

V4NT0M · 24 Sep 2013 at 15:52

Yea, if you need it to be accurate get a meter from DX or something.

twist3d0n3 · 24 Sep 2013 at 15:56

SPL meter

anderp · 24 Sep 2013 at 17:08

Only a proper piece of equipment will do the job. You can probably hire one?

ZXSpectrum · 24 Sep 2013 at 17:28

If its for a noisy neighbour complaint there are people/organizations like Neighbours from hell website/forum that you can hire a high spec one that the results are admissible in court

Gooner Leroy · 24 Sep 2013 at 17:39

It'd probably be useful to know what you want monitoring.

Lowe · 24 Sep 2013 at 18:01

The Decibel iPhone app is actually surprisingly accurate. We have a Cirrus Research meter that cost a couple of grand, and after calibrating the iPhone with it, Decibel gives results within a single dB of the CR, certainly up to 100dB. I've not tried anything beyond that.

Westyfield2 · 24 Sep 2013 at 18:42

I've got a couple of cheap sound meters. They're alright, but not as accurate as a friends one that cost a few grand.

SexyGreyFox · 24 Sep 2013 at 18:47

I bought one from Maplins about 2 decades ago for about £25 and I compared it to the £3000 one we had at work and it was highly accurate.
I use mine to set each band members volume and if I can get them all playing at 110db each + another 5 on top for the bass then I know we will have a good mix.

mattyfez · 24 Sep 2013 at 19:01

It's for quite a random reason, I play the guitar (acoustic) and there's a forum where there's some talk of older guitars getting louder, certain types of construction and bracing and wood type being different volumes, one guy used an iPhone app and got 92db from a guitar that's kinda known for being a bit of a cannon, would be interesting to see some comparisons.

Although I too am highly dubious about the a db meter app, especially as Ive read most 'cheap' mics can't hear anything above so many decibels, and it varies from device to device,galaxy s3 aapparently can't register anything above 82db, where as the s2 can apparently go up to 95db. Then you've got to hope the app is actually accurate.

Be nice to have an easy way for a bunch of people to test without having to fork out for any specialist equipment, as it's only a bit of fun.

mattyfez · 24 Sep 2013 at 19:06

GrimsbyLAD said:
Smart phone is crazy inaccurate.. Mine recorded 92.6db from a gas turbine. No chance

It might be accurate but from what ive read, a lot of non specialist mics such as those on phones simply can't register over a certain amount, so you probably just maxed it out.

dirtychinchilla · 24 Sep 2013 at 19:10

Why don't you try the app out?

mattyfez · 24 Sep 2013 at 19:15

dirtychinchilla said:
Why don't you try the app out?

Well this is the thing, the most pro looking app on Android has a disclaimer saying s3 which I have can only go up to like 82db or whatever, other phones such as the s2 can register a bit higher so for a remote forum comparison it's kinda flawed from the get go.

I'll try the app, but i imagine that kind of limit won't cut it. 90db is a shed load louder than 80.

http://www.google.co.uk/search?site....9.3220.YrR8Uppwc7o#biv=i|2;d|8uIYmrkMD4ld_M:

SexyGreyFox · 24 Sep 2013 at 19:42

mattyfez said:
It's for quite a random reason, I play the guitar (acoustic) and there's a forum where there's some talk of older guitars getting louder, certain types of construction and bracing and wood type being different volumes, one guy used an iPhone app and got 92db from a guitar that's kinda known for being a bit of a cannon, would be interesting to see some comparisons.

Although I too am highly dubious about the a db meter app, especially as Ive read most 'cheap' mics can't hear anything above so many decibels, and it varies from device to device,galaxy s3 aapparently can't register anything above 82db, where as the s2 can apparently go up to 95db. Then you've got to hope the app is actually accurate.

Be nice to have an easy way for a bunch of people to test without having to fork out for any specialist equipment, as it's only a bit of fun.

It may not be accurate but my smartphone app helps me to adjust all my guitar and amp volume settings which it is capable of doing.
So for instance I use a James Tyler JTV-59 which emulates many famous guitars but the four I use on stage have different volumes which are noticeable.
I put my amp on clean and then using my guitars Workbench software I'm able to adjust each sound to exactly the same db and then save those four guitars into my presets.
On stage I noticed that my main 4 amp sounds weren't quite accurate (clean, distortion, lead solo and heavy distortion) so using the smartphone app I made 3 of them exactly the same db and the lead channel is 6db louder which is perfect on stage.
Last weekend all my guitar & amp sounds were bob on

mattyfez · 24 Sep 2013 at 20:43

Dimple said:
It may not be accurate but my smartphone app helps me to adjust all my guitar and amp volume settings which it is capable of doing.
So for instance I use a James Tyler JTV-59 which emulates many famous guitars but the four I use on stage have different volumes which are noticeable.
I put my amp on clean and then using my guitars Workbench software I'm able to adjust each sound to exactly the same db and then save those four guitars into my presets.
On stage I noticed that my main 4 amp sounds weren't quite accurate (clean, distortion, lead solo and heavy distortion) so using the smartphone app I made 3 of them exactly the same db and the lead channel is 6db louder which is perfect on stage.
Last weekend all my guitar & amp sounds were bob on

Interesting stuff, I've downloaded 'sound meter' which seems accurate and very responsive at low volume, which is great for setting a base line volume for instruments, and then just turning them up relative to each other.. I can't get it to breach 84db though which suggests a hardware limitation on the microphone on the phone. The app devs have suggested the s3 mic can't cope with anything more than about that.. So sounds about right.

Useful but a big un amplified acoustic can probably hit the 90's at close range.

Hmm, maybe I'll have to choose my next phone based on mic quality lol!

SexyGreyFox · 24 Sep 2013 at 21:46

mattyfez said:
Useful but a big un amplified acoustic can probably hit the 90's at close range.

So place the phone further back.
I put mine about 10 foot away and all the volumes are around 70db but my amp is on a lowish volume.

mattyfez · 24 Sep 2013 at 22:11

Dimple said:
So place the phone further back.
I put mine about 10 foot away and all the volumes are around 70db but my amp is on a lowish volume.

In the words of homer Simpson 'doh'!

That should work perfectly! Dunno why that didn't occur to me!

So some ground rules for testing could be the phone (mic) should be placed exactly (5) feet parallel to the sound hole. And the software used for measuring should be the same.