Hello,
I tried out the RTA app indoor. Here is what it says the QSC HPR 122i's frequency response is in my living room.
One is full range mode; the other is high pass mode. Interesting. For what it's worth, it more or less agrees with my ears' perception of this speaker: smooth but not overly bright.
This is the free version, I don't have the option to choose "internal mic" so what it reads may also be influenced by the iPod Touch's mic resonse. They said the iPod Touch mic has bass rolloff.
I am pretty impressed with what this app can do on iPod Touch. I think if I buy something, I'll get the FFT. Much more useful than the 1/3 octave RTA. The useful part of the RTA is during a live situation if my only adjustment tool is a 31-band PA, which may not solve some real problems anyways.