Symphony etiquette
Okay, I wanted to give a few pointers for enjoying live classical music, in case you've never been to a performance. (Although I know YOU wouldn't do anything really embarrassing, I have seen some pretty flagrant lapses in etiquette, so this might prevent any problems that might arise, and hopefully maximize your enjoyment of the performance)
First, it might be a good idea to familiarize yourself with some of the more popular composers and their big works (Beethoven's 9th Symphony, Handel's Messiah, Mozart's Requiem, etc.) Knowing the general structure of different types of compositions and the styles that different composers use in their work can give you an idea of what to expect when you see it performed live. This will be important later on, as I'll explain further in a bit.
Next, get the tickets. Although opinion differs, I tend to like sitting right in the middle of the auditorium, about twenty to thirty rows from the front. Sure, if you're a little myopic, you might not be able to see the mole (excuse me, I mean "beauty mark") on the cheek of the second bassoonist, but REALLY... Although it doesn't matter as much in Benaroya Hall, where the acoustics are good enough that you can hear everything clearly even up in the nosebleed seats, this position maximizes the effect. If you're too close to the stage and off to one side, you might hear one section of the orchestra or choir better than the other, and the balance of sounds might be off a bit. Further back, this effect mostly disappears.
Next, attire. It's customary to at least wear something semi-formal (I'm required to wear a tux, but you obviously don't have to). No one will kick you out for wearing jeans, flip-flops and a wife-beater tee shirt, but it's kind of tacky. So men, wear slacks and a nice collared button-up shirt at a minimum, and ladies, either the same or a tasteful dress (rule of thumb: if you're unable to sit down without exposing genitalia, wear something else.. yes, unfortunately, tragically, I've seen it myself, sitting front row center)
Try to show up early, if only to get decent parking, but also so you don't delay or interrupt the performance. Sometimes they won't even let you into the auditorium if you arrive after the the conductor is onstage. For longer pieces, like Messiah, they pause after the first movement or two to let stragglers get to their seats, but this isn't universal. Oh, by the way, please silence the electronica. The stage manager will remind you of it just before the conductor walks out on stage, but be polite and have cell phones, signal watches and pagers silenced or turned to vibrate mode when you first sit down, so you don't have to worry about it later.
Okay, so the performance is about to begin. Be sure to read through your program so you know what pieces they'll be playing (I'm sure you already know, since you chose to see this performance, and I assume it wasn't just a random choice). This is where a familiarity with classical music will help you, because you need to know when to applaud and sit quietly. It is customary to applaud only after the completion of the entire piece, or at the intermission if the piece comes in two long parts (Messiah, for instance, or a number of symphonies by Mahler, which have movements as long as other composers' whole symphonies) Concertos typically have three movements (and customarily are arranged fast-slow-finale), while symphonies range from three to five movements, depending. If a single movement has a notable soloist, it is sometimes acceptable to applaud that individual, or if it's a REALLY popular movement performed REALLY well (the Hallelujah chorus of Handel's Messiah almost always gets applauded, because people just like it) When in doubt, just follow the lead of the rest of the audience; even during what might be considered inappropriate times, performers rarely discourage applause, so you're pretty safe regardless. Oh, and it's usually customary for the conductor and any soloists to take a bow, leave the stage and come back for a second round of applause. If the performance was really good, the audience might continue clapping and they could come out for a third bow, but this doesn't always happen.
Sleeping is discouraged, of course, but since I've also been guilty of falling asleep during long performances (not when I'm onstage, mind you, just as an audience member), I can't really fault anyone, but snoring is definitely out.
That's all I can think of at the moment; if you've got questions, feel free to ask me.

Updated: Nov. 9, 2006
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