ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: [1]   Go Down

Author Topic: hanging mics system  (Read 2464 times)

andy nguyen

  • Newbie
  • *
  • Offline Offline
  • Posts: 7
hanging mics system
« on: February 27, 2014, 02:42:02 pm »

Hello all,
I am a returning member.  I have some questions to ask.  Please help.
I am a member at San Gabriel Mission Church in San Gabriel California.  Our chapel basically is a eco chamber due to its brick wall and cement floor construction.  The choir is located at wing left of the alter.  We have 5 hanging microphones DPA 4098H.
We have the microphones locate about 1.5 feet in front and 2 feet above the first row.  They face directly to the second row.  We have two rows of choir members and total around 25 to 30.
 The issue is we get complain from the people in the back of the church that they can not hear the sound from the choir. And if we try to gain, the system proms to feedback very quickly.  We tried to eliminate the feedback with equalizer, but the sound come out very bad since we have to reduce almost all the frequencies in vocal range 100 hz to 3 kHz.

We think we need to lower the microphones some more, but the issue is they may get stolen.  I have three questions:
1) What else can we do to eliminate the feedback and increase the volume. 
2) Should we set the microphone zigzag form or on the same line like we have now?
3) Can you suggest me some hanging system that we can lower the microphone during mass and rise and lock after mass?
4) Or Can you suggest any trusted installed in Los Angeles Area that we can use.

Thank you very much

MBGR199
Logged

Jeff Carter

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 363
  • Kitchener, ON, Canada
Re: hanging mics system
« Reply #1 on: February 27, 2014, 03:06:04 pm »

Tell us a bit more about your situation:
-How big is the room?
-Any instrumental accompaniment for the choir?
-Any monitor speakers for the choir?
-Would it be possible to group the singers closer together (possibly even in three rows?)

For a choir of 25-30 I would probably use two microphones, not five. More mics than necessary usually means worse sound due to comb filtering and can also reduce gain before feedback. Bunch the choir together as closely as you can, and tell them to sing louder. (And if people at the back can't hear, tell them to move forward... seriously.)

Also, have you tried any other microphones, or played around with the angle of the mic? The 4098H is a supercardioid pattern, which means that rejection of sound coming directly from the rear is rather poor compared to a cardioid.
Logged
Mothers, don't let your babies grow up to be physics PhDs

Tom Young

  • Global Moderator
  • Hero Member
  • *****
  • Offline Offline
  • Posts: 620
Re: hanging mics system
« Reply #2 on: February 27, 2014, 03:29:43 pm »

You've provided a pretty clear description of the space and the problem you are faced with.

What about the FOH ldspkr system:

what is it (brand and models) ?

How is it deployed ?

Where are the ldspkrs relative to the choir mic's ?

Was this system measured and optimized using one of the modern-day complex measurement systems and by an experienced measurement person ?

Is the choir not being loud enough at the rear the only real complaint ?

If not, what are the other problems ?
Logged
Tom Young
Electroacoustic Design Services
Oxford CT
203-888-6217

g'bye, Dick Rees

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 7424
  • Duluth
Re: hanging mics system
« Reply #3 on: February 27, 2014, 03:33:30 pm »

Hello all,
I am a returning member.  I have some questions to ask.  Please help.
I am a member at San Gabriel Mission Church in San Gabriel California.  Our chapel basically is a eco chamber due to its brick wall and cement floor construction.  The choir is located at wing left of the alter.  We have 5 hanging microphones DPA 4098H.
We have the microphones locate about 1.5 feet in front and 2 feet above the first row.  They face directly to the second row.  We have two rows of choir members and total around 25 to 30.
 The issue is we get complain from the people in the back of the church that they can not hear the sound from the choir. And if we try to gain, the system proms to feedback very quickly.  We tried to eliminate the feedback with equalizer, but the sound come out very bad since we have to reduce almost all the frequencies in vocal range 100 hz to 3 kHz.

We think we need to lower the microphones some more, but the issue is they may get stolen.  I have three questions:
1) What else can we do to eliminate the feedback and increase the volume. 
2) Should we set the microphone zigzag form or on the same line like we have now?
3) Can you suggest me some hanging system that we can lower the microphone during mass and rise and lock after mass?
4) Or Can you suggest any trusted installed in Los Angeles Area that we can use.

Thank you very much

MBGR199

I'm with Jeff that 5 mics are too many.  2 or 3 will be plenty, but I also agree that a cardioid pattern might be better.  But (there's always a but)...

The mics are only part of the system and the system is deployed in an enclosed space so that all plays into the equation.  You do not give any dimensions or distances and those are helpful to know.

There will be two basic divisions of sound within the room:

1.  Direct sound field.

2.  Reverberative sound field.

The best seats in the house will be those which get all or the greater part of their sound directly, with few or no reflections.  The sound quality and intelligibility will diminish the further the listeners are in that portion of the room where the greater part of the sound is reflected sound...with the attendant "multiple time arrivals".

The boundary between these two areas is called the "critical distance".

So the microphones are only one small part of the equation.  Turning them up isn't going to lengthen the critical distance.  On the contrary, it may decrease it.  Having your room coverage come from well-chosen, well-designed and properly deployed speakers is a very large part of the equation.  To get intelligible sound to the rear of the room may require one or more sets of delay speakers, synchronized with the mains to bring the area of direct (or primarily direct) sound closer to the rear of the room.

One church install I did used some small, near field "studio monitors" about 2/3 of the way to the rear.  Some of the members complained that they had spent money for speakers which "weren't doing anything".

I had them sit in the rear of the church, played some music over the system, then turned the delays off.

"Where'd the sound go?"

You don't have to have them loud, you just have to have them time-aligned to properly reinforce the direct sound wave as it proceeds from front to rear.  Keeping the sound from the loudspeakers from bouncing off the walls is necessary.  Reducing reflections from a flat rear wall by hanging some tapestries or some such can also help...as long as the materials are fire resistant (to local code).

I'd advise you to find a professional audio person to evaluate your entire system.  Very often nothing more than proper aiming may be a fix.

It's not just the mics...

Logged
Pay no attention to the man behind the curtain...

Mike Maly

  • Full Member
  • ***
  • Offline Offline
  • Posts: 109
Re: hanging mics system
« Reply #4 on: February 27, 2014, 03:42:30 pm »

Room acoustics...strange things they are...and most people ignore them.


Sent from my iPhone using Tapatalk
Logged
-Maly Sound:
Hear the difference

andy nguyen

  • Newbie
  • *
  • Offline Offline
  • Posts: 7
Re: hanging mics system
« Reply #5 on: February 27, 2014, 04:02:34 pm »

Hello all,
I am a returning member.  I have some questions to ask.  Please help.
I am a member at San Gabriel Mission Church in San Gabriel California.  Our chapel basically is a eco chamber due to its brick wall and cement floor construction.  The choir is located at wing left of the alter.  We have 5 hanging microphones DPA 4098H.
We have the microphones locate about 1.5 feet in front and 2 feet above the first row.  They face directly to the second row.  We have two rows of choir members and total around 25 to 30.
 The issue is we get complain from the people in the back of the church that they can not hear the sound from the choir. And if we try to gain, the system proms to feedback very quickly.  We tried to eliminate the feedback with equalizer, but the sound come out very bad since we have to reduce almost all the frequencies in vocal range 100 hz to 3 kHz.

We think we need to lower the microphones some more, but the issue is they may get stolen.  I have three questions:
1) What else can we do to eliminate the feedback and increase the volume. 
2) Should we set the microphone zigzag form or on the same line like we have now?
3) Can you suggest me some hanging system that we can lower the microphone during mass and rise and lock after mass?
4) Or Can you suggest any trusted installed in Los Angeles Area that we can use.

Thank you very much

MBGR199

Thanks all very much for your inputs.  I will measure, sketch, taking pictures of the room when I come to the church next time.
Logged

Don Sullivan

  • Newbie
  • *
  • Offline Offline
  • Posts: 39
Re: hanging mics system
« Reply #6 on: March 23, 2014, 09:10:05 am »

+1 to all the sound advice here, and I will add my two cents. Remember the 3:1 rule. The distance between your mics should be 3X the distance between your mics and the choir. With that few voices I would use a single pair of mics in an x/y (crossed) in the front of the center of the choir. Also you could try arcing the choir ( if possible) so they are standing in a curve whose focal point is your microphones.
Other tricks I have used:
Get a digital console or system controller. Add 10-20 MS delay on your mains, or put a 10-20 MS delay on your choir mics. Has the effect of pushing your speakers 10-20 feet farther out in front.
Try phase reversing one or more of your choir mics to reduce feedback.
Roll off the bass and high treble on your choir mics. Reduce the mic inputs to the frequencies everyone is singing on.
Try large diaphragm condenser mics on stands as opposed to pencil condensers, For some reason I get more volume before feedback with large diaphragm mics. Don't give up. Try negative mixing. Reduce the volume of the other items in your mix so the choir is loud enough in the total  mix. This is tough when the choir doesn't start the service.
Logged

Doug Hammel

  • Full Member
  • ***
  • Offline Offline
  • Posts: 106
Re: hanging mics system
« Reply #7 on: March 23, 2014, 07:09:03 pm »

Hello all,
I am a returning member.  I have some questions to ask.  Please help.
I am a member at San Gabriel Mission Church in San Gabriel California.  Our chapel basically is a eco chamber due to its brick wall and cement floor construction.  The choir is located at wing left of the alter.  We have 5 hanging microphones DPA 4098H.
We have the microphones locate about 1.5 feet in front and 2 feet above the first row.  They face directly to the second row.  We have two rows of choir members and total around 25 to 30.
 The issue is we get complain from the people in the back of the church that they can not hear the sound from the choir. And if we try to gain, the system proms to feedback very quickly.  We tried to eliminate the feedback with equalizer, but the sound come out very bad since we have to reduce almost all the frequencies in vocal range 100 hz to 3 kHz.

We think we need to lower the microphones some more, but the issue is they may get stolen.  I have three questions:
1) What else can we do to eliminate the feedback and increase the volume. 
2) Should we set the microphone zigzag form or on the same line like we have now?
3) Can you suggest me some hanging system that we can lower the microphone during mass and rise and lock after mass?
4) Or Can you suggest any trusted installed in Los Angeles Area that we can use.

Thank you very much

MBGR199

How close are the mics to each other. I bet they are to close and you are getting some cancellations. Try this, only use mic 1,3,5 you will probably get more gain and then one step further use mic 2 and 4. That should sound the best. Five mics is definitely too many for that size choir.
Logged
Doug Hammel

dougcvaudio@gmail.com

ProSoundWeb Community

Re: hanging mics system
« Reply #7 on: March 23, 2014, 07:09:03 pm »


Pages: [1]   Go Up
 



Page created in 0.042 seconds with 23 queries.