If there is no conductor, who will check the tickets?
I was just talking about something similar with my daughter the other day. She is a sophomore studying music ed, and is more involved in concert and marching bands than orchestras, but I believe some of what she said is relevant here.
On a football field, players need to look to the conductor simply because there can be a significant sight/sound lag across the length of the field. She said if you are somewhere that you can’t see the conductor, you look to the lead snare. And if you can’t find the lead, look to any percussionist.
I imagine the sound lag would be les on a concert stage, but she commented on how difficult it can be to hear different instruments, depending on acoustics, how the band is seated, etc. So again, it is safer to trust your eyes than your ears. Far different from my experience playing bass in a rock band, where all I needed to do is get tight with the drummer.
She is 1st chair flute, and said one time she was uncharacteristically spacing out, and forgot to count the next flute entrance. Unknown to her, no one else was counting - instead, they all simply looked to my daughter and waited for her to raise her flute. When my daughter blew the entrance, the whole section did as well! 
She also said as a general rule, without a conductor slow pieces will get slower and slower, and fast pieces will speed up.
This is absolutely correct. I just did some back-of-the-envelope sums, and for the third movement of Sibelius’ second symphony (chosen because it’s a particularly fast one and because I’ve got a recording handy) I measure it at about 8-10 quavers per second.* The time lag to hear these half-a-note late is as little as 17 metres :eek: (and there was me thinking that the basses are always dragging 
) And far more importantly, the sound you are actually hearing might not be dominated by the direct line, but is bouncing around the hall before reaching you.
*I checked Isaac Stern’s conclusion of the Barber violin concerto, too, which clocks in at about 13 quavers/sec. (IIRC Hilary Hahn goes faster, but I don’t have a copy of her recording.) However, this doesn’t involve the whole orchestra playing at that rate!
This shall not go unpunished, Zebra. Someday, when you least expect it…! :dubious: 
I will preface this by saying that I know nothing about music. Zippo. Anyway, I always had an uninformed hunch that the conductor was most important in rehearsals, as a couple folks upthread said. But then, this weekend, I went to the Cincinnati Symphony Orchestra to hear a performance with a Special Guest Conductor. I thought to myself, “Well, if they just bring this guy in for a night, he must be doing something up there.” Are the guest conductors usually brought in far enough ahead of time that the orchestra gets the benefit of rehearsing with them? Or is the Special Guest Conductor just a gimmick to lure philistines like me?
Those Damn Engineers are all in the toilet anyway! 
The guest conductor rehearses the orchestra. Bringing a new conductor up cold at a performance would range somewhere along the scale from pointless to potentially disastrous. If you stood the conductor up there without rehearsal, the orchestra would just play the piece in whatever ways they were used to playing it.
The role of a conductor is to guide the orchestra in the direction of his or her idea of what the piece is supposed to sound like. About 80 percent of the conductor’s work is done before the performance. During the performance, the conductor is mostly responsible for ensuring that everyone starts and stops at the same time and to give occasional reminders and cues. There’s a lot more to what a piece sounds like than that.
Brief hijack, but this is the main problem that opera singers on big stages confront. The sound from the orchestra in the pit is really late getting to you, and you’re usually well out of synch with what you’re hearing. The sight of the conductor is your only lifeline, and you have to learn to ignore your ears and just use your eyes.
Both my dad and my sister have sung for years with a major W. Penna. chorus and orchestra which regularly uses Special Guest Conductors (out-of-town bigshot conductors, famous movie-score composers, local TV anchormen, etc.) as a ticket-sales-generating PR shtick. They rehearse so intensively before the SGC even picks up the baton, my sister said, that his stick-waving is pretty much irrelevant. One time the regular conductor, knowing of the SGC’s technique and highly disdainful of it, explicitly told them just to pay attention to the lead violinist and choral section heads, and to ignore the SGC.
Isn’t that basically what a chamber orchestra is? Granted chaber is a lot smaller, but usually they don’t perform with a conductor.
Anyway it’s not too bad without a conductor. In band out director actually will go sit down and tell a completely random person to start the piece with a big breath (or something). So long as the piece is simple (if we’re sight reading) or we’ve practiced it a lot (for more complex pieces) it goes fairly smoothly. Things like fermatas are solved by slight rules you learn in things like Drum Major conducting lessons. Since DMs often conduct like the band would play if they weren’t there (because of the logistics of being on a field and moving) you get rules like “hold a fermata as long as twice the original note value.” Other things like ritardandos and accelerandos are just taken naturally, it’s not too hard to “feel” the rate at which the pulse should slow down.
In fact every year at our outdoor end of the year concert the band shows up orchestra and choir by putting on acting with the music, and the director is always a character and every year so far we’ve had to play without the conductor for some pieces.
My first year: Harry Potter and the Prisoner of Azkaban. This one was only a few bars, conductor was dumbledore and he did, something I can’t quite remember what too long ago.
Second year: Hook. Director was peter pan and for the latter half of the piece acted and came back after the fight near the end finished. In fact this one was harder because we had to repeat the section multiple times while they were fighting so no autopilot.
Third Year: Star Wars. Director was Darth Vader. He got into a lightsaber fight with the kid playing Luke during a relevent section in the song.
Granted an Orchestra with strings, or strings and winds is slightly different but i figure it’s at least similar enough.
Also, for reference before someone says we’re just smalla dn that’s why… our band is about 180 people.
TLDR version: As long as the ensemble is good it doesn’t matter.
“A lot smaller” is exactly the difference. Four musicians can work without a conductor much more easily than 100 can.
[Ex-DCI drum corps contrabass bugle player shako on]
Feild sound lag is a HUGE ssue in large formations, in many cases if you pay attention, some sections notably percussion rarely wander outside of eeither 35 yard line for the very reasons you stated above. There is no “sight” lag and sometimes you even rehearse sections where you learn to play anticipating the beat a bit so that it sounds right up at the press box.
Timing full line brass attacks and releases in wide formations is an art form all itself.
Where formations and equipment do not permit a full section to see the drum major, a key person who can see is designated and they become the guide for tempo for the section.
So what if someone who knows nothing of conducting (or of playing music in general) picked up the baton? If I walked up there and started waving at random, would the orchestra sound like crap?
Hey! Hey!
But it’s the second violins who did almost ALL of the volunteer work for our community orchestra. All the organizing, bookkeeping, publicity, etc. Even setting up the chairs for rehearsal.
Those lazy brass just showed up and played.
That’s because second violins are more grateful.
Typically the orchestra is rehearsed by the resident conductor, then the guest conductor steps in just before the performance for a final rehearsal or two. By the time he shows up, the technical details have been worked out, and all the orch needs to learn is his interpretation differences.
If the resident is really good, he may know in advance what those interpretation quirks might be, and prepare the orchestra for them in advance.
I have been involved with very large performing groups (full orch, boys’ choir, mixed choir, solos and ensembles for the same work) and there may be 5 different conductors, each rehearsing their groups independently. They come together for a final rehearsal with the guest conductor. Some works even had choirs from 2 different sources (community, college) that never worked together until the end.
It’ll sound much the same as without a conductor, because they’ll be doing their best to ignore you.
That’s pretty interesting. I hope I’m not taking us too far afield from the OP here, but it seems like the Special Guest Conductor runs the risk of hitching his wagon to an orchestra who might not have either the desire or the preparation to play the music the way he wants. In the scenario described by Elendil’s Heir, the SGC just has to lump it if the orchestra ignores him. In your scenario, the SGC has more control but is still dealing with musicians who have done most of the prep with someone else. Surely the musicians are pros and want to make the SGC’s concert fit the SGC’s vision. But, if you’re the SGC and you care about the subtlest facets of the music, aren’t you in danger of attaching your name to a performance you didn’t really manage?
Isn’t that basically what happened back when John Williams took over the Boston Pops? The players had no respect from him and refused to follow at first, IIRC. He did eventually win, though.