ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: [1] 2  All   Go Down

Author Topic: Amps under stage. Bad idea?  (Read 6328 times)

Jamin Lynch

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1862
  • Corpus Christi, TX.
Amps under stage. Bad idea?
« on: January 22, 2015, 11:27:59 am »

I have a small system upgrade at a local church coming up. We are going to replace their old power amps with new Crown xti series. Currently the amp rack in located at the back corner on the stage and is very visible. They would like to have it out of sight. Unfortunately due to the layout there is just not a good place to put the amp rack. We were thinking about putting it under the stage.

Here's the details:

The music style is light contemporary. Don't think they will be hitting the amps hard.

1- Crown xti4002 for tops
1- Crown xti1002 bridged for sub
2- Crown xti2002 for monitors

Air flow: Front to back. Which is about my only major concern since the warm air will be blowing under the stage.

The stage is about 30" tall, 15ft deep 40ft wide. Completely "open" underneath. I told them we will have to have a hinged trap door with a vent panel in front for ventilation, of which they agreed to do.

Do you think locating the amp rack under the stage in this situation would be a bad idea? Any suggestions?
« Last Edit: January 22, 2015, 11:35:37 am by Jamin Lynch »
Logged
"At first you don't succeed, go back to the drawing board."

Josh Millward

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 713
  • Meridian, MS
Re: Amps under stage. Bad idea?
« Reply #1 on: January 22, 2015, 11:43:32 am »

Do you think locating the amp rack under the stage in this situation would be a bad idea? Any suggestions?

Hi Jamin,

I have done exactly this same thing with great success in the past. However, the amplifiers I was using were different models and they blew from back to front and the stage was partially open to the front and sides so there was more than adequate airflow.

I would think that as long as the space was dry, having the exhaust blowing under the stage would not be a problem. How well sealed is the space? If it is highly sealed, then I could see cutting a vent in the far side (away from the amplifiers) and installing a low RPM ventilation fan that is switched on when the amplifiers are also switched on. That way you could at least keep some air moving through the space.

Have fun and good luck!
Logged
Josh Millward
Danley Sound Labs

claude cascioli

  • Newbie
  • *
  • Offline Offline
  • Posts: 38
Re: Amps under stage. Bad idea?
« Reply #2 on: February 19, 2015, 08:52:56 pm »

Hi Jamin,

I have done exactly this same thing with great success in the past. However, the amplifiers I was using were different models and they blew from back to front and the stage was partially open to the front and sides so there was more than adequate airflow.

I would think that as long as the space was dry, having the exhaust blowing under the stage would not be a problem. How well sealed is the space? If it is highly sealed, then I could see cutting a vent in the far side (away from the amplifiers) and installing a low RPM ventilation fan that is switched on when the amplifiers are also switched on. That way you could at least keep some air moving through the space.

Have fun and good luck!

better use qscs the crowns are garbage
Logged

Ray Aberle

  • Classic LAB
  • Hero Member
  • *
  • Offline Offline
  • Posts: 3414
  • Located in Vancouver, WA (and serves OR-WA-ID-BC)
    • Kelcema Audio
Re: Amps under stage. Bad idea?
« Reply #3 on: February 20, 2015, 12:40:17 am »

better use qscs the crowns are garbage

Unsubstantiated, or...........?

 :-\

Logged
Kelcema Audio
Regional - Serving Pacific Northwest (OR, WA, ID, BC)

Scott Holtzman

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 5353
  • Ghost AV - Avon Lake, OH
    • Ghost Audio Visual Systems, LLC
Re: Amps under stage. Bad idea?
« Reply #4 on: February 20, 2015, 02:22:48 am »

Yeah he just did this in another thread,  what's up with this guy?
Logged
Scott AKA "Skyking" Holtzman
River Delta Audio is now:

Ghost Audio Visual Solutions, LLC
Cleveland OH
www.ghostav.rocks

frank kayser

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1382
  • Maryland suburbs of Washington DC
Re: Amps under stage. Bad idea?
« Reply #5 on: February 20, 2015, 10:42:38 am »

The only caution I'd have is that amps down low may collect a bit more dust than amps in other locations.  Do the maintenance and clean often. Actually the Crown with its front-to-back airflow may be of additional help as one can see the dust build up on the amp front.


Crown XTI being garbage?  What's not to like? They've been good to me...  And I like QSC, too.   
frank
Logged

Ray Aberle

  • Classic LAB
  • Hero Member
  • *
  • Offline Offline
  • Posts: 3414
  • Located in Vancouver, WA (and serves OR-WA-ID-BC)
    • Kelcema Audio
Re: Amps under stage. Bad idea?
« Reply #6 on: February 20, 2015, 12:21:11 pm »

Yeah he just did this in another thread,  what's up with this guy?

He doesn't know how to use the "quote" function, that's for sure. Haha. But really, unsubstantiated heresy has no place in these forums, in my humble opinion. Rather then spread things like that, people should be posting their real-world experiences, as in.. "I used XLY widget, and it was broken out of the box," or "My newly purchased Framis didn't have the "punch" that I was looking for, when connected to my Lorean Wonkensnoodle."

-Ray
Logged
Kelcema Audio
Regional - Serving Pacific Northwest (OR, WA, ID, BC)

Josh Millward

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 713
  • Meridian, MS
Re: Amps under stage. Bad idea?
« Reply #7 on: February 20, 2015, 06:45:21 pm »

better use qscs the crowns are garbage
Oh no, horror of all horrors!!! Most of the amplifiers in that situation were Peavey! Oh noes! (It is true, though they were mostly CS series amplifiers...) There were also a couple Crest Audio amplifiers in there, too.

However, there were no QSC nor Crown amplifiers to be found.

Claude, please learn how to use the Quote function properly. You put your message AFTER the part that says /quote and outside the brackets.

Also, there is NO latitude given to people who post unsubstantiated claims like that in these forums. Have you had a problem with the Crown amps? Please tell us all about it because we would love to hear it.
Logged
Josh Millward
Danley Sound Labs

Charlie Zureki

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1244
  • South Eastern Michigan (near Windsor)
Re: Amps under stage. Bad idea?
« Reply #8 on: February 21, 2015, 03:11:26 pm »

Oh no, horror of all horrors!!! Most of the amplifiers in that situation were Peavey! Oh noes! (It is true, though they were mostly CS series amplifiers...) There were also a couple Crest Audio amplifiers in there, too.

However, there were no QSC nor Crown amplifiers to be found.

Claude, please learn how to use the Quote function properly. You put your message AFTER the part that says /quote and outside the brackets.

Also, there is NO latitude given to people who post unsubstantiated claims like that in these forums. Have you had a problem with the Crown amps? Please tell us all about it because we would love to hear it.

  +1    I'd love to hear his claims too.   ;)

  Hammer
Logged
Do it the right way....don't be a Dino!

Scott Carneval

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 974
    • Cenero Audio Visual
Re: Amps under stage. Bad idea?
« Reply #9 on: February 24, 2015, 05:34:51 pm »

  +1    I'd love to hear his claims too.   ;)

  Hammer

As a previous user of the Crown Macrotech series (the real ones, MA3600, MA5000vz) I can say I'm more than a little disappointed with the XTI's.  The series 2 are marginally better than the original.  As a Crown dealer, I'm probably not allowed to call them garbage on a public forum, but I certainly won't argue with anyone who does. 

I'll give you two real-world examples of XTI's that I've installed.  One is a nightclub where one XTI4002 was powering the tops and one XTI4002 was powering the subs.  After about a year the power switch became 'sticky' on one of the amps.  It wasn't that anything spilled on it, it just didn't glide in and out like it used to. No amount of spray or lube that I tried would help it glide. I even took it out and tried cleaning it, but it wasn't dirty. This is a plastic button that rides in a plastic hole, and it's like the plastic warped or something.  You're supposed to push it in for 'ON' and push it again and it pops back out for 'OFF'.  Well it would get stuck 'ON' so you'd have to use a key or a small tool to pry it back out to the 'OFF' position. Unfortunately if you didn't pry it just right the entire button would fall inside of the amp and if you were lucky it would get stuck in the 'ON' position, or if you were unlucky it would get stuck in the 'OFF' position and you would have to remove the cover at 11pm after the sound guy called you frantic that the show was about to start and he couldn't get the tops to turn on and the promoter was pissed and the crowd was getting anxious.  Don't ask me how I know.  So we replaced the power switch on that amp, and a month or two later the other amp exhibited the same issue.  Nothing was ever spilled on these amps, and it's not in a particularly dusty environment.  This is a non-smoking club.

Second example: Another nightclub.  Two subs running off of each side of a Crown MA2400.  They've been working fine for about 12 years, but the MA2400 finally called it quits.  The client didn't want to pony up for a big boy amp, so I sold him a Crown XTI4002.  This was a 2-ohm load, but the XTI is rated for 2ohms.  I install the amp, reset the limiters and gain structure in the DSP as the XTI has a different voltage gain than the MA2400, and finish testing and go home.  At 11:30, after about an hour and a half of being driven hard but NOT clipping, the XTI failed completely and wouldn't turn back on.  'Surely this was a dud' I thought, so I installed another one the next day.  After about a half hour of testing (running it hard as I knew they would too) this amp failed too.  So I went to Guitar Center and picked up a RMX2450 (needed it same day) and fast-forward to 2 years later and the RMX is still working. 

Your mileage may vary.
Logged
Pages: [1] 2  All   Go Up
 


Page created in 0.057 seconds with 21 queries.