After working with the Encoder Checker some more, I still think it’s pretty great, (although I agree with others that it should definitely have an automatic input gain control, not only a level and peak limiter recommendation, which might work fine in some cases but isn’t optimal if you’re splitting hairs on level. Also peak limiting is controversial and not normally recommended for MFiT in any of the documentation I’ve seen. Normally, simply lowering the input gain to the encoder is recommended.)
But I do question the lack of the Apple AAC codec, and the Fraunhofer AAC codec being called “iTunes +” in the AAC preset. The Fraunhofer is really dissimilar to the Apple in at least one important way: the encoder clip level and inter-sample peak total numbers. The Fraunhofer encoded AACs have about 1/3 to 1/2 the number of clip and ISP levels when analysed in afclip than Apple MFiT AACs for the same program. Those numbers are one of the most important things as far as Apple is concerned in preparing Mastered for iTunes files. And while third party tools like the Encoder Checker are not currently approved for MFiT, they might be in the future, so if you’re simply preparing for standard iTunes or preparing for MFiT, the Apple codec would be a more accurate representation of what will be sold in the iTunes store.
So I’d like to ask if the Apple AAC codec could be added to the Encoder Checker, as that could rightfully be called “iTunes +”. I believe the Sonnox uses the Apple codec in their encoder checker, on Mac and Windows, and that it’s already there in Quicktime on both platforms. The Apple codec on Windows is extremely close to the Mac as far as clip and ISP numbers go, so it would be perfectly usable on Windows to my mind. It’s close enough for Apple to call it the same thing (“iTunes +”) on both Mac and Windows.
Also I believe the Encoder Checker could really use an indication of the total numbers (clip and ISP) after a render, preferably a pop up in a text file, similar to the readout in the Mac terminal “afclip” command, and conforming to the numbers and sensitivity of their readings.