Saturday, September 25, 2010

Pros & Cons of the Music Business (Part I)

Lacking Credit Information

  One of my favorite pass-times has been visiting record stores to see what new discovery might be waiting for me there. I would pour over the jacket credits of unfamiliar contenders looking for familiar, creditable contributors. I might recognize the producer, engineer, studio musicians, etc. If my curiosity matched my confidence and available cash, I'd buy it, take it home, listen to it and learn what and who I did or did not like about it. This would inevitably lead me back to the record store with an expanded appetite for more. A snowball effect.

  Gone are those days. Our search for music now is via the internet. Sure, we can check out short, low-res samples if we find something, but how do we find something in the first place? Who produced it? Who recorded it? Who even plays on it?  Those artists deserve credit and if I saw it, I'd be more inclined to buy it (or not). This lack of credit information has cut my risk-taking down to almost zero.

   The online shopping experience is lacking and overwhelming. And posting reviews by end-users with opinions that are all over the place is a waste. How do you go about finding something new? These days I tend to rely on my friends who I can gauge, and who can gauge me. I'll check out Pandora Radio, etc. to try to find new artists that match my tastes, and this technique has certainly opened a few doors, but it is very inefficient compared to rifling through record bins checking credits.

   I find it incredible that in this age of instant electronic information, the whining record companies are missing out on such a huge sales opportunity. Why are we forced to play a white elephant game? Intrigue me by telling me what is in the package. Give me some background. Get me involved in the music and the artist. Tell me about the recording venue, the approach, the equipment, the instruments, etc. Teach me so that I may become a connoisseur and share it with my friends. Include anecdotal information like; "this song incorporates the new...", or "Steve Gadd was called in to record the incredible drum part for the title track "Aja" and laid it down in one take, without a rehearsal". Create some "buzz". Information is going to be the first step towards enticing me to purchase new music and currently the record industry is lacking this key component.

Wednesday, September 1, 2010

Symmetrical vs. Non-symmetrical Layouts

“Symmetrical vs. Non-symmetrical Layouts

Audio has been a serious part of my life for more than 40 years. Having said that, never in my experience has the notion of non-symmetry in audio layout been regarded as a good thing. However, I see it being done frequently these days. Open most any magazine about home theater and you'll see pictures of layouts without a seat centered between the speakers. Where is "the money seat"?  Sadly, there can only be one designated location where all the speakers can converge at the same space, at the same time, and at the same amplitude. To have two seats flank the spot where all the magic lives means a large investment is not paying off to its full potential. Sure, you can adjust levels and delays electronically to any location, but it will still be severely skewed acoustically between left and right if it is not centered in the room. The design hierarchy must be: set-up, calibration, acoustics, and equipment. Even a stereo boom box can't be perceived as stereo unless your head is oriented correctly in front of it.

I have also been seeing dedicated listening rooms where the both the speaker and listener positions are deliberately positioned off-center of the side walls. This is very odd! Why would someone design such a layout? It turns out that the idea is to avoid the width axial room modes. Sounds like a great idea until you realize that even with a relatively small theater width of 16 feet, the f1 axial mode cancellation is 35.3Hz., which means:
a) This frequency is the fifth note up from the bottom of a piano, so except for keyboards, it is not likely that a soundtrack will play 35.3Hz. long enough to cause much of a standing wave issue. 

b) This wave is 32 feet long.  You may ask how far off-center you'll have to move to be out of the cancelled wave? You'll have to shift about 3' to gain only about 5dB. And what about f2, which is a crest at 70Hz. and f3, which is another trough at 105Hz.? And what about the length and height axial modes? Well, room modes are most everywhere, and as you move out of one, you likely move into another. In addition, they become more plentiful as you move towards a boundary.

c) If we also move the speakers, aren't we likely to exasperate the room modes? Yes. 

d) If we move ourselves and the speakers closer to one side, aren't we likely to perceive a difference in low frequency pressure between right and left? Yes, and also hear differences in timbre, spatial ques, imaging, etc. all due to boundary effects. If we were to measure the same signal being fed from both L and R speakers at the skewed listening position, they would be very different. And no, a digital signal processor ain't gonna fix it.

It is true that we want to avoid placing ourselves and the speakers in areas that will exacerbate room modes. It is also true that in an enclosed space, we must make many compromises. The best choice for speaker/listener positions are to avoid the fundamental height and length modes and sacrifice the width. This has to do with human perception and the fact that by design, we are much more sensitive to the horizontal plane than we are to the median or lateral planes. I'll sacrifice a few rare low frequency irregularities for constant linear mid and high frequency tonal balance, and accurate soundstage and imaging any day.

Lastly, a rectangular room is more predictable and easier to treat acoustically because of symmetry. Irregularly shaped rooms are difficult to computer model, and difficult to control acoustically. Symmetry in audio is always a good thing.