Thanks Ian!
Just to clarify I only boost the rear speakers by +3dB but leave the side surrounds at the same level as the front speakers.
For the untrained ear (meaning most people) I agree that auto calibration is better than nothing if someone doesn’t have an SPL meter. However, in my experience once a person hones their critical listening skills they can get pretty close to the same settings as auto calibration or an SPL meter gives for sound level (distance at some frequencies if you’re really good) by ear alone. Though I totally understand that for most people auto calibration is far more practical.
A perfect example of the ear sometimes being better than auto calibration was when in my apartment I invited over a friend who use to master demo tapes for local bands. When I demoed the opening battle in Master and Commander he immediately said that my subwoofer distance was off. He adjusted it by ear and I ended up with the best sounding crossover from the mains to the sub I have ever had.
One of the reasons I keep bringing up this topic is that I fell prey to thinking that auto-cal and auto-EQ would do all the work for me and because they are machines will be more accurate than my hearing. Only by accident did I realize that speaker/seating placement and eventually things like room treatments played a much greater role in the quality of sound I’m getting from my system than whether or not I was using EQ or the auto calibration settings. I think the best example of this is that despite all the science and experience Axiom puts into their speaker designs you still put things through double blind listening tests to make sure it works in practice.
Another time I only realized by accident what furniture did to in room sound when I added a futon (previously just had a matrass on the floor) and suddenly had all the “life” sucked out of my music. Later I found that by elevating my mains it returned much of the ambiance I had lost when I put that giant sound absorbing futon in the middle of my room. Most people will never experience this because the room they put their speakers in is likely laid out and furnished before adding the speakers.
In more general terms living abroad especially in “third world” countries I learned that human perception is far more powerful than most Westerners (steeped in the “scientific method”) realize. We’re taught to trust our instruments and distrust our senses. I’m a trained interrogator and can say without a doubt that I can detect a lie better than any polygraph machine I’ve seen. There is a reason El Al Air Lines uses trained interviewers as their primary means of detecting terrorists boarding airplanes . . . they work better than baggage and body screening machines. Pacific islanders were able to navigate between islands by being able to feel the reflected swells on their legs hanging in the water coming off islands as far as 30 miles away. The list of seemingly amazing things human perception is capable of is almost endless but most people, especially Westerners disregard them because it’s what our cultures teach us. Yet audio, especially music, is IMO very much about perception. (steps off soap box)
Those measurements of what auto EQ does would be very interesting to see.
Cheers,
Dean
