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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => Installed Sound/Contracting => Topic started by: Joseph D. Macry on February 15, 2011, 10:55:45 AM

Title: Motorized lift for permanent install?
Post by: Joseph D. Macry on February 15, 2011, 10:55:45 AM
Renovating an old theater on an Army post. Latest change: Army is providing the speakers, and wants them on motorized hoists.  I have only used motors for truck-in-truck-out rigs.  What do you think of this for permanent install?

Text from client: "THE contractor will install all government finished equipment: Hang 4 JBL 4888s on both the left and right side of the proscenium opening. Speakers will be hung on motorized cable picks for ease of operation. Each array of speakers will be aimed for optimal audio coverage in lower part of auditorium Subs will be hidden in front of stage but will still give maximum coverage. Equipment does not include extended electrical pig tails, contractor to provide."

I read this as hanging the arrays on chain hoists. Not real clear on who provides the motors.

Joseph Macry
Austin TX
Title: Re: Motorized lift for permanent install?
Post by: Brad Weber on February 16, 2011, 08:13:49 AM
Hang 4 JBL 4888s on both the left and right side of the proscenium opening. Speakers will be hung on motorized cable picks for ease of operation. Each array of speakers will be aimed for optimal audio coverage in lower part of auditorium Subs will be hidden in front of stage but will still give maximum coverage.
Definitely military, "You will provide good coverage with this system because we said you would, don't argue that physics crap with me!"

It does sound like they want chain hoists with a motor controller.  The bigger issue may be whether anyone has verified how this may attach to structure and if the structure can support it.  And whether there was actually any effort associated with assessing that the design concept defined and OFE equipment being furnished are appropriate.

Title: Re: Motorized lift for permanent install?
Post by: Bruce Olson on February 16, 2011, 07:58:03 PM
Renovating an old theater on an Army post. Latest change: Army is providing the speakers, and wants them on motorized hoists.  I have only used motors for truck-in-truck-out rigs.  What do you think of this for permanent install?

I'm with Brad on this, I'd worry more about the coverage than the motors, although I would get confirmation that a structural engineer has reviewed the pick points and load calcs. It sure sounds like they don't know if the speakers are appropriate, only that some higher-up saw they were laying around and said they needed to be used, never considering they might not be right. I especially like the wording on the Subs. I'd ask them for how they should be aimed or put in a disclaimer about "within the capabilities of the OFE" along with the price for design of the coverage.
Title: Re: Motorized lift for permanent install?
Post by: Charlie Zureki on February 23, 2011, 11:43:41 PM
I'm with Brad on this, I'd worry more about the coverage than the motors, although I would get confirmation that a structural engineer has reviewed the pick points and load calcs. It sure sounds like they don't know if the speakers are appropriate, only that some higher-up saw they were laying around and said they needed to be used, never considering they might not be right. I especially like the wording on the Subs. I'd ask them for how they should be aimed or put in a disclaimer about "within the capabilities of the OFE" along with the price for design of the coverage.


   Hello,

   If Joseph quoted the Base's  RFQ word for word...

   The originator (Base) wants a bid for the labor & equipment (motors, etc.) to hang the eight speakers (four speakers each side), and the power/signal cabling to the speakers and aim them for the MAIN floor.   

   There is a lot more information needed to properly bid on this job.

   A site survey is needed for the ability to hang these motors/speakers, cable runs/paths, accessible electrical drops (for motors) and  some  predictions in regards to speaker outputs.

  The bid verbage seems to indicate that it was taken from an existing, previous quote by another vendor.

  Do your homework, or otherwise "no bid" the project. Good Luck,

  Hammer

 
   
   

   
 


 
Title: Re: Motorized lift for permanent install?
Post by: Geoff Doane on February 28, 2011, 12:39:51 PM
Renovating an old theater on an Army post. Latest change: Army is providing the speakers, and wants them on motorized hoists.  I have only used motors for truck-in-truck-out rigs.  What do you think of this for permanent install?

It sounds like you already have the job, and this is a change order?

If so, you should be able to talk to the project engineer, hammer out the details, name your price, and they either accept your terms, or deal with it later.  I'd be a bit concerned about the reference to "pig-tails".  That sounds like something that might be used on a one off show, not a permanent install.

GTD
Title: Re: Motorized lift for permanent install?
Post by: Brad Weber on February 28, 2011, 02:40:02 PM
Renovating an old theater on an Army post. Latest change: Army is providing the speakers, and wants them on motorized hoists.  I have only used motors for truck-in-truck-out rigs.  What do you think of this for permanent install?
If you were asking about the concept of using motors for permanently installed speaker systems I have done this multiple times.  Usually this was done for ease in servicing the speakers.  In other situations it was to allow readily dropping the house system to let touring groups hang their systems.  For a concert hall project it was to allow the speakers to be hidden when not needed and dropped down into a 'show' position when needed (and to the floor for servicing).