If this is not the place to pose inquiries about standard playwriting procedure, then I apologize, but I have a few questions regarding a musical that I am currently writing.
First, I should mention that I am writing a full-length musical. I know that the norm is to have a first act of a musical run longer than the second. But what is the usual proportion in minutes?
And while we are on the topic of duration, how long is TOO long for a musical? I know some epics like Miss Saigon, Phantom, and Les Mis run pretty long, but they are exceptions that can justify their slightly extended length. So, how long would be too long for a musical? What time duration should I shoot for not including the intermission?
Also, in my musical there are ALOT of characters. I am trying to take Sondheim's Company concept of using the primary actors to double as a chorus, but to do this within the context of my musical it would require (by my estimation at least) that the actors/actresses be double (and in some cases triple and even quadruple) cast. I know this has worked in the past with some musicals like RENT, but what is the general thought of using this device? It's certainly a cartoony, comical sort of show, so if anyone recognizes that the actors are pulling double/triple/quadruple duty, it really won't matter, but I wanted to get you guys' take on it before I begin writing.
Here is what I think is a prime problem that I see from your post in general:
"It's certainly a cartoony, comical sort of show, so if anyone recognizes that the actors are pulling double/triple/quadruple duty, it really won't matter, but I wanted to get you guys' take on it BEFORE I BEGIN WRITING."
It seems as if you are thinking thinking thinking too, too much.
Begin! Begin! Begin!
You seem to be concentrating on where it is going rather than where it will take you.
Just write what you want. Don't worry about the time or the amount of characters (Yes you can double quadruple cast. I saw Chazz Palmenteri do "A Bronx Tale" where he played, as one critic wrote, "I've seen one-man shows before, but Mr. Palmenteri plays an entire borough.") and get your first draft done.
Then the real work begins.
To aid you: Stephen Sondheim just published in December a book called "Finishing The Hat" which is taken from the title of a song from "Sunday in the Park With George."
Pick it up. Read it. Study it. He is the master. It will be money well-spent. On the book jacket it says it is a theatrical book/memoirs that belongs in the ranks of Moss Hart's "Act One" and Arthur Miller's "Timebends." I agree.
A first act should run about an hour and 30 minutes or less.
The second no more than an hour.
You don't need a chorus and these days might try to avoid.
No one expects there to be a chorus.
Keep your cast size small. 4 people are enough for a chorus...anything more is a bonus.