[*Scotty*]

I recently ran across a very useful app for the iPhone/iPod from Studio Six. This is a RTA app that
covers the bandwidth from 32Hz to 16kHz with octave or 1/3octave resolution.
  It has a 120 dB dynamic range from 0dB to 120dB. There is adequate resolution to reveal bass response problems. This is just the thing for adjusting speaker location and toe-in using pink noise to achieve the flattest response.
You can now retire that Rat Shack SPL meter and move into the 21st. century.

Scotty

[MaxCast]

Hi Scotty,
I have that app but wonder about the accuracy of it.  Have you read any reports on how it fairs to a calabrated mic and computer set up?

[Phil A]

I noticed the App but just got my iPhone a few weeks back and have not gotten to look into it more.  Isn't it $9.99?  I do have a real $600 one third octave RTA with a calibrated mike so was a bit curious about it.  It will probably be a bit before I get to it.  I noticed there are a whole bunch of RTA apps.  One was $179.99 I believe.  Far behind on stuff (and in process of some equipment changes) and probably won't get to it before later summer or early fall.

[JRace]

Any measurment system is only as good as the mic.
How good (acurate and consistant) can the mic in an iPhone be?

[Phil A]

Any measurment system is only as good as the mic.
How good (acurate and consistant) can the mic in an iPhone be?

That was my inital thought.  I thought it just might be a cool App to have.  I don't know anything about the iPhone mic (not to mention I've only had it three weeks) however, when it comes to phones, I know that B&O has good stuff in the guts of their home cordless phones.  Not that I'm comparing the two, just an observation.  For all I know the iPhone might not even have as good a mic as my old Radio Shack SPL meter which has limitations.  I guess I'm still curious about it that at some point I'll probably give it a try.

[MaxCast]

My hope is that the iphones limitations are consistent and can be corrected through the software.

[Russtafarian]

I use the free RTA app from Studio Six.  It doesn't replace Room EQ Wizard and a measurement mic, but it's a great portable device for sniffing out basic acoustic issues.  I used it all weekend at the The Show Newport, both to help set up the VMPS room and to sniff out feedback frequencies when I set up and ran the PA for the live performances.

The $20 suite of audio apps got a good review in TAS last month but I haven't popped for it yet.

Russ

[JRace]

My hope is that the iphones limitations are consistent and can be corrected through the software.

Exactly! We need to measure a few iPhones and see if they are consistant...if so then this could be a usefull app. Just need a couple dozen iPhones, and a calibrated mic...

[sts9fan]

As long as the response is linear it can be useful in a qaulitative way. 

[*Scotty*]

The RTA app has limitations due to the platform its running on. The  Studio Six website has a couple of FAQ pages that enumerate the  issues affecting the RTAs accuracy which are specific to the model of  iPhone the app is running on.
  See links:    http://www.studiosixdigital.com/iphone_3gs_microphone.html   http://www.studiosixdigital.com/fft_or_rta.html
   At the end of the day it is a handy BASIC tool for diagnosing frequency  response problems in a stereo system and will not replace a more  sophisticated RTA or FFT program with a calibrated mic.

Scotty

[MaxCast]

Just to be clear.  I don't expect it to be as good as a calibrated mic set up but just want to know if it's 10 dB off or just 2-3.  If the latter then yes, good enough to see where the major problems are.  I have the FFT, btw.
It's been awhile since I've been to dig6, thanks for the links, Scotty.

[Phil A]

I use the free RTA app from Studio Six.  It doesn't replace Room EQ Wizard and a measurement mic, but it's a great portable device for sniffing out basic acoustic issues.  I used it all weekend at the The Show Newport, both to help set up the VMPS room and to sniff out feedback frequencies when I set up and ran the PA for the live performances.

The $20 suite of audio apps got a good review in TAS last month but I haven't popped for it yet.

Russ

Thanks for the info - I downloaded the free App and paid the $0.99 for no ads.  I also downloaded their $0.99 SPL Meter.  For those prices it's a no brainer even if it gets used just a couple of times.  I have friend who are not audiophiles but care enough that if it can identify a bad room problem and tame it a drop it is a good use for me.