SPL Meter lol

Works like a charm. Don't know how the MIC on the iphone is weighted, but it should get the job done.

But I still don't think it's a channel trim issue, since it has more to do with the content.

 

"Decibel" or "SPL meter" for 0.99 are probably the best for the money, a couple of 1.99 offerings are out there too.
Or if you feel extravagant- there are full blown RTA/FFT modules from Studio Six Digital and faberacoustical that run upwards of $20+, yes- expensive for i-phone apps I'll admit, but still about half the price of the rat shack meter, and really cheap compared to "real instrumentation" that does the same basic stuff.

The internal mic is pretty far from optimal, but the guys putting these programs together have done a decent job of compensating, the higher end programs will give you A, C and other weightings for SPL numbers- not exactly calibrated, but for relative purposes more than adequate to the task at hand.

 

pete,

what do you think if the iphone as a sound meter platform. assuming an external mic is attached. a good/pro level external mic...

that studio 6 seems to be a nice set of apps. they even include settings for calibrating an external mic.

 

I don't see measurements on an i-phone holding up in court or anything like that quit yet, but I know Studio Six is working with Rational Acoustics on porting a Smaart lite or something like that into their suite, so depending on what you need to do with it, it could very well be a viable option for many types of basic sound measurement.

 

Sony

 

There is also an auto optimization setup on page 24 that you could look into if you haven't done it already. If it is anything like my Denon, it will adjust levels and delay.