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View Full Version : Live audio setup for a school dramatic performance




superuser2
May 2, 2008, 04:33 PM
What, in terms of audio equipment goes into an economical but decent (mostly economical) school musical?

I'm thinking of an Alesis MultiMix 12 (or maybe 8) in terms of a mixing desk, but what else is needed? Can someone explain/point me at an explanation of wireless microphones and what must be set up?

My understanding of it is that the microphone receivers plug in via XLR to the mixing desk, which in turn puts out an RCA input, which is then wired to an amp, then the amp the speakers.

I guess what I don't understand are the types of microphones, cabling (difference between XLR, 1/4", and RCA), and amps/preamps/whatever else goes into it.

(I have run a sound board in a fairly well-equipped auditorium, but barely know how to go about setting up a live system.)

Equipment will probably be rented.

Thanks for any advice.

(This is a hypothetical question [there really is a performance coming up, but I'm not in charge of selecting equipment], as I think understanding this type of setup will help me understand sound engineering better.)



Killyp
May 3, 2008, 01:21 AM
DON'T use 'home' speakers. You MUST use speakers designed for PA use or you will completely wreck them.

A MultiMix isn't strictly necessary unless you also want to record it.

How many Mics do you want to plug in? I would recommend an 'all-in-one' PA system, particularly the Yamaha Stagepas system (300 watt and 500 watt models) as I have the 500 watt version and it's absolutely fantastic. Also has a (surprisingly flexible) built in mixing unit and comes with amps etc... already.

Up to 4 mics plug straight into the mixing console, and you can always attach a mixing desk to them to extend them even further (this is what I do, I also use a pair of bass-bins with them to improve the bass response when I'm doing gigs).

CanadaRAM
May 3, 2008, 01:35 AM
Your best bet is to... well in advance ... go to the rental company and outline your requirements and ask to be led though the components and cabling.

You do NOT want to be learning what's what on the day of.

Wireless microphones are either handheld like a normal performance microphone, or are miniature (lavalier) mics that are hidden in a performer's costume, with a body pack radio transmitter. The radio receiver(s) are positioned near the mixer, and hook up to the mixer with conventional XLR or 1/4" cables. With wireless mics you MUST budget for new batteries all around for each performance. Also have at least one spare set ready to go backstage for emergency replacement. Test the system in advance so you can change frequencies if necessary to keep away from interference (like radio stations, taxi and police radios, etc.)

(note -- make sure to mute each performers' mics as they go offstage, or you will regale the audience with a bunch of unintended dialogue... can be very embarassing....) Good idea to have the action blocked out on paper and mark the cues.

You probably also want a pair of mics picking up the stage sound for the non-mic's performers. These can be flown from the lighting rig, or on stands in front of the first row of the audience (obvious issues there with sight lines and audience interference potential. If the mics are being used for sound reinforcement in house, you have to worry about feedback from the front of house system. If they are purely for recording, then no problem.

Other alternatives for stage mics are boundary layer (or 'mouse') mics on the front lip of the stage (on foam to reduce the noise of feet).

Make sure you know what Phantom Power is, and which mics do (and don't) need it.

superuser2
May 3, 2008, 05:04 PM
Alright, well, I found out we're getting a good load of stuff, but the invoice didn't give model numbers. Still, though, I can get out of math to watch/help with setup...

There are no wireless microphones, but eight wired ones (on 50' cables with stands). We'll probably have four or five of them in front of the stage for the singers to walk up to or project to, and use individual mics wherever we can. My biggest worry, though, is some acts that have two rows of people and the people in the back need to be heard. How would you handle this?

I don't have any hanging mics nor do I have wireless mics, so I'm not sure what to do, other than tell them to project really well...

hakukani
May 3, 2008, 09:24 PM
If you are not using wireless mics, your best choice is to use Crown PCC -160 (phase coherent cardioid) microphones. They are a boundary mic that you place on the lip of the stage. Three across the front of the stage, with one at stage center will probably be sufficient.

Hanging mics usually sound bad and just don't work, because of timing issues between the mic elements, and distance. The human voice is surprisingly directional, and micing from above doesn't buy you much gain before feedback.

Musical theater is one of the most difficult sound jobs in the world, and this is exacerbated by the fact that most amateur companies end up making sound the lowest priority.

(BTW, the best place for wireless lavs is not clothing. The best place is to mount the mic in the middle of the forehead, at the hairline and eq'ing to sound natural (boost of 3-6dB at 4 to 5KHz). If you can't mount there, then the best place is just over or under the ear. The theory being that the mic moves with the actor's head, and mic-to-mouth distance stays fairly consistent.)

Break a leg on the show. I wish you well.

superuser2
May 4, 2008, 10:30 AM
OK.

I will have 8 omnidirectional mics. Should I see if I can change that?

I'm kinda thinking I want to change all or some of them to SM58s. Would that work from a few feet away?

Is there something that would pick up a lot of the stage but not the audience? (What you suggested probably wouldn't work as this is a rental stage that I doubt we can attach stuff to.)

hayd93
May 4, 2008, 02:46 PM
OK.

I will have 8 omnidirectional mics. Should I see if I can change that?

I'm kinda thinking I want to change all or some of them to SM58s. Would that work from a few feet away?

Is there something that would pick up a lot of the stage but not the audience? (What you suggested probably wouldn't work as this is a rental stage that I doubt we can attach stuff to.)

There is the AKG1000s they pick up well but at the same time dont pick up mutch noise from behind.they are a condencer though so you will need phantom.

Killyp
May 4, 2008, 05:05 PM
I agree with Hayd.

The boundry mics mentioned earlier are very good, but tend to be much worse off than you would expect when the acoustics of the theatre/workspace aren't ideal (which they almost always aren't).

Look at the C1000s, a line of them along the front of the stage should give you a good sound.

Also, don't try using an SM58 at distance. Dynamic mics (the SM58 falls under this category) are highly sensitive to something called the proximity effect. This means the sound changes noticeably as you move away from/towards the microphone. The closer you get, the more bass you get, the further away you are, the thinner the sound will be - and will really sound dreadful. Therefore, SM58s tend to sound best at around a foot (with vocals), and don't sound so good at most other distances.

C1000s don't suffer from this, and as a result, are much more suitable to picking up sounds from further away. They also have a much more controlled (and very precisely cardiod) pickup pattern, unlike the SM58 which can be quite omnidirectional at times (even though it is technically cardiod).

This wikipedia article (http://en.wikipedia.org/wiki/Microphone#Microphone_polar_patterns) may be of some use. It explains how different microphones pick up sound differently.

superuser2
May 4, 2008, 06:13 PM
I have read excessively on the subject of microphone directionality (omni/cardioid/hypercardioid) and to a lesser extent dynamic vs. condenser.

If you think the AKG C 1000s will work in a row across the stage, I will try to make that happen. (I would probably still want two SM58s to give to vocalists who can hold them or to put on stands.)

I'm thinking of one SM58 on a stand in the middle to be used by vocalists who can walk up to it...

How many would you use for an approx. 45 ft stage? (I am aware of the 3 to 1 rule... the average intended pickup location would be somewhere between 2 and 5 feet. Would 3 suffice?)

If the rental company can't provide us with these, or they're too expensive, what else should I ask for?

EDIT: It just occured to me that there's also a much smaller singing chorus which is needed for some acts, though only two at the same time as the main stage. Will I need to get more mics (possibly more expensive and less likely to happen) or is there another way to handle it? It's around 15 people...

hakukani
May 4, 2008, 07:17 PM
I agree with Hayd.

The boundry mics mentioned earlier are very good, but tend to be much worse off than you would expect when the acoustics of the theatre/workspace aren't ideal (which they almost always aren't).

Look at the C1000s, a line of them along the front of the stage should give you a good sound.

Also, don't try using an SM58 at distance. Dynamic mics (the SM58 falls under this category) are highly sensitive to something called the proximity effect. This means the sound changes noticeably as you move away from/towards the microphone. The closer you get, the more bass you get, the further away you are, the thinner the sound will be - and will really sound dreadful. Therefore, SM58s tend to sound best at around a foot (with vocals), and don't sound so good at most other distances.

C1000s don't suffer from this, and as a result, are much more suitable to picking up sounds from further away. They also have a much more controlled (and very precisely cardiod) pickup pattern, unlike the SM58 which can be quite omnidirectional at times (even though it is technically cardiod).

This wikipedia article (http://en.wikipedia.org/wiki/Microphone#Microphone_polar_patterns) may be of some use. It explains how different microphones pick up sound differently.

AKG C1000s are not suited for micing stages. Sorry to disagree, but I spent nearly a decade doing sound for musicals, and have done over 40 productions. The only place I've used a C1000 was for a backstage chorus, and they were quite near the microphone. If you really need to have a mic upstage, then you're better off with a shotgun mic aimed straight where you need it. You still need to be careful.

One of the problems with directly miking some players and not others, is the psychology of having some folks louder than others. If the contrast is great, then the person with lower volume will seem even quieter. If there are consistent levels, then your audience becomes habituated to the quieter level, and listen harder.

If you insist on using regular mics, or PCCs aren't available across the stage, be sure to place them 1 foot or lower from the deck of the stage, or better yet, placed on foam pads. The reasoning is twofold. One, it looks better, and two, there can be comb filtering from the direct sound and the relected sound from the deck reaching the mic at slightly different times. Also, don't use too many mics across the front. You need to follow the three to one rule on stages.

There's some good stuff here:

http://www.geocities.com/lowfreq20/theatre.htm#MIC

superuser2
May 6, 2008, 07:49 PM
The stage and lighting came today, sound will come tomorrow.

How do I deal with a stage that rumbles under a lot of footsteps? Should I just mute the lows on the mics on dance numbers?

hakukani
May 7, 2008, 01:53 AM
The stage and lighting came today, sound will come tomorrow.

How do I deal with a stage that rumbles under a lot of footsteps? Should I just mute the lows on the mics on dance numbers?

If there's no singing and no tap dancing, mute the mics during dance numbers.
Pull out everything below ~80 Hz, and if you can, make the music louder during the dances to cover the elephant steps.

What show are you doing?

superuser2
May 7, 2008, 07:01 AM
It's "A Salute to Broadway" - a collection of a bunch of stuff.

There are a couple dance numbers that also have singing... the others I can just run with the mics off. Thanks for the 80Hz figure, that will probably help a lot.

Well, I get my equipment today. I'll let you know what I get and then maybe ask for more specific advice later...

superuser2
May 8, 2008, 06:57 AM
I got my equipment.

There's nothing that picks up more than a couple feet away, so I'm putting a row of five mics across the stage and will have to get it through the performers' heads that anything and everything they say must be into one of them.

My chorus was right in front of the speaker and I got feedback on it, so I'll move them further back.

Thanks for the help. I'll see how this works out today.

hakukani
May 9, 2008, 01:31 PM
I got my equipment.


My chorus was right in front of the speaker and I got feedback on it, so I'll move them further back.

Thanks for the help. I'll see how this works out today.

The chorus should be behind the speakers.

superuser2
May 10, 2008, 08:43 AM
Opening night has passed without major catastrophe. Most of my mistakes were bringing the master down, starting the music, and not bringing the master back up again until a few seconds later...

A microphone came unplugged once, but we sent a backstage crew person out between that act and the next and it was restored without issue.

I have one singer who's very dynamic and brings the microphone in and out of the range of her mouth. I've been trying to push it in the quiet parts and bring it down in the louder parts, but it's kind of hard. Is there another way to handle that?

hakukani
May 10, 2008, 03:05 PM
Opening night has passed without major catastrophe. Most of my mistakes were bringing the master down, starting the music, and not bringing the master back up again until a few seconds later...

A microphone came unplugged once, but we sent a backstage crew person out between that act and the next and it was restored without issue.

I have one singer who's very dynamic and brings the microphone in and out of the range of her mouth. I've been trying to push it in the quiet parts and bring it down in the louder parts, but it's kind of hard. Is there another way to handle that?

Yeah, but you don't have a compressor.;) Just keep riding that fader!
Glad it's working out. I think everyone's forgotten to bring the master up at least once.:o

Remember, the better the talent on stage, the easier it is to help them sound better. It's sound reinforcement.
There's neither a 'talent' fader or a 'suck' knob.