BAASnotes.com – Bay Area Audiophile Society

Null Testing and Listening Testing of “Mastered for iTunes”

In this video, Ian Shepard of Production Advice in the UK compares a CD track to both its “raw” AAC coded form and a “Mastered for iTunes” rendition. I think that most of you will jump to the punchline early on, but the journey is interesting (for audio geeks).

On a related note, I wish that the audiophile industry would do more null testing to answer simple questions like: “does this cable sound different from that one?” It’s really not that difficult.

Bob

Audio Primer: Training Your Ears

Continuing on our recent technical theme, here’s a great site for training your ears to detect and describe sonic anomalies. It’s harder than you think. If you like what you hear, please support the author by buying one of the products on Quiztones. (The Golden Ears material is the sine quo non of the field – it’s great.)

One more bit of knowledge that you need to make pronouncements like “the lower mids are muddy” is a working definition of “bass/midrange/treble.” I personally use the mental hook of dividing the audio range into three ranges, separated by two easy-to-remember “corner frequencies”: 150hz and 1500hz. Piece of cake. You can find a more elaborate definition in the graphic.

Finally, it’s fair to ask about how these map to the musical concepts that we know or learned in school. The keyboard graphic below helps with this aspect.

Bob

Audio Primer: How the Pros Use EQ and Compression

Audiophiles are taught that equalization (EQ) and compression are BAD. However, used judiciously, they are useful or even GOOD.

Joe Gilder’s “Home Studio Corner” web site is one of the best resources on the web for learning how good-sounding recordings are put together. No, Joe’s home studio is neither Skywalker nor Abbey Roads in sophistication. But it’s quite nice, and Joe is a natural and giving teacher.

The material on EQ is a good building-block for the room correction work that we’ll do. The compression video is also quite interesting, showing that the technique has uses beyond the “loudness wars.”

Enjoy.

Bob