ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 [2] 3 4   Go Down

Author Topic: Community S-218s? Any experience with it?  (Read 9799 times)

Onlin Barna

  • Newbie
  • *
  • Offline Offline
  • Posts: 29
Re: Community S-218s? Any experience with it?
« Reply #10 on: December 30, 2012, 04:58:30 pm »

AGAIN-the SIMPLE answer.  Music is NOT a constant level.  The OSHA limits are for constant level-like with machinery.

HENCE the reason I said DYNAMIC RANGE or crest factor.  If you are using the PEAK output capacity-then the AVERAGE level will be well below that.

There is no "simple answer" for the "SPL" of music.  Therefore a DOSE meter is the best way.

Just take an SPL meter (your choice) and run a loudspeaker up to its "maximum" (I will let you determine what that is). with music playing.  Put it 1M away and see if the reading is anywhere near the rated SPL.

Is the meter wrong?  Is the loudspeaker rating wrong?  Let's assume neither.  But what IS wrong is the actual measurement-how it is done-how the loudspeaker rating was arrived at and so forth.

Once you start doing measurements and find that they don't "stand up" to what you think-THEN you should start to question things-and that will lead to a better understanding of what is going on.

So the limits are for for example sound level of a sinus wave.
Logged

Caleb Dueck

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1007
Re: Community S-218s? Any experience with it?
« Reply #11 on: December 30, 2012, 05:03:55 pm »

Also, at what frequency.  112dB music with a large 1-6kHz bump would make me walk out fast, while 112dB below 80 Hz is common.

Part is due to how the ear works, part is how transient (relates to crest factor) much LF really is. 
Logged
Experience is something you get right after you need it.

Ivan Beaver

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 8885
  • Atlanta GA
Re: Community S-218s? Any experience with it?
« Reply #12 on: December 30, 2012, 06:19:40 pm »

So the limits are for for example sound level of a sinus wave.
NO.  If you attempt to get any modern loudspeaker to reproduce a sine wave at the max rated output-it will burn up VERY quickly.  THe exception would be loudspeakers with built in protection.

Sine waves would be fine for a couple of cycles-but not continuous.  I haven't tried it-but i bet 10 seconds or less would kill pretty much any loudspeaker at max/peak power ratings. Especially if the "peak power" is the RMS wattage and not a "peak wattage" as calculated from the peak of the sinewave.

The ratings are derived using noise with a specific crest factor and freq shaping.
Logged
A complex question is easily answered by a simple-easy to understand WRONG answer!

Ivan Beaver
Danley Sound Labs

PHYSICS- NOT FADS!

g'bye, Dick Rees

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 7424
  • Duluth
Re: Community S-218s? Any experience with it?
« Reply #13 on: December 30, 2012, 06:34:44 pm »

So the limits are for for example sound level of a sinus wave.

For Ivan:
Logged
Pay no attention to the man behind the curtain...

Onlin Barna

  • Newbie
  • *
  • Offline Offline
  • Posts: 29
Re: Community S-218s? Any experience with it?
« Reply #14 on: December 30, 2012, 07:31:10 pm »

NO.  If you attempt to get any modern loudspeaker to reproduce a sine wave at the max rated output-it will burn up VERY quickly.  THe exception would be loudspeakers with built in protection.

Sine waves would be fine for a couple of cycles-but not continuous.  I haven't tried it-but i bet 10 seconds or less would kill pretty much any loudspeaker at max/peak power ratings. Especially if the "peak power" is the RMS wattage and not a "peak wattage" as calculated from the peak of the sinewave.

The ratings are derived using noise with a specific crest factor and freq shaping.

"limits" I meant "OSHA limits".
Logged

Caleb Dueck

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1007
Re: Community S-218s? Any experience with it?
« Reply #15 on: December 30, 2012, 07:59:24 pm »

"limits" I meant "OSHA limits".

I think you're confusing OSHA limits with max output at 1m.  A speaker that can put out 129 dB long term (EV QRX 212 for example) at 1 meter is going to be around 105 dB if the audience size isn't that large.  If a large area outdoors, maybe 85-90 dBA (or less).  Add 16-20 dB for the sub bass, which dBA doesn't take much account of, and that 90 dBA could be 110dB in the sub bass region.  90 dBA has a long time under OSHA before it's dangerous (don't recall right off). 

For subs in particular, find out how many dBA you want in the audience area (say 100 dBA), add 20+ dB, and that's what the subs will be doing in the audience.  Using inverse square law, find out how many dB are needed, long term, at 1m.  You could well need 160 dB at 1m, to have enough, without worrying about OSHA limits. 

Look at Danley, Bassmaxx, JTR, maybe even VTC for some good options.  My guess is that the quantity and amp power needed are many multiples higher cost than expected.
Logged
Experience is something you get right after you need it.

Ivan Beaver

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 8885
  • Atlanta GA
Re: Community S-218s? Any experience with it?
« Reply #16 on: December 30, 2012, 08:17:40 pm »

I think you're confusing OSHA limits with max output at 1m.  A speaker that can put out 129 dB long term (EV QRX 212 for example) at 1 meter is going to be around 105 dB if the audience size isn't that large.  If a large area outdoors, maybe 85-90 dBA (or less).  Add 16-20 dB for the sub bass, which dBA doesn't take much account of, and that 90 dBA could be 110dB in the sub bass region.  90 dBA has a long time under OSHA before it's dangerous (don't recall right off). 

For subs in particular, find out how many dBA you want in the audience area (say 100 dBA), add 20+ dB, and that's what the subs will be doing in the audience.  Using inverse square law, find out how many dB are needed, long term, at 1m.  You could well need 160 dB at 1m, to have enough, without worrying about OSHA limits. 

Look at Danley, Bassmaxx, JTR, maybe even VTC for some good options.  My guess is that the quantity and amp power needed are many multiples higher cost than expected.
And just to make it even more confusing-consider the fact that the A scale was never intended for loud SPL's.  I think the upper limit was around 80dB-but I don't recall off hand.

But that does not keep people from "measuring it"-or using a meter on the A scale to attempt to come up with a reading.

Is it accurate?  I'm not sure-but when you use a scale quite a bit out of the intended range-exactly what does it mean?
Logged
A complex question is easily answered by a simple-easy to understand WRONG answer!

Ivan Beaver
Danley Sound Labs

PHYSICS- NOT FADS!

Ivan Beaver

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 8885
  • Atlanta GA
Re: Community S-218s? Any experience with it?
« Reply #17 on: December 30, 2012, 08:22:19 pm »

"limits" I meant "OSHA limits".
OSHA doesn't care about wattage-or sinewaves or even loudspeakers for that matter.

On the noise side of their "concerns", it is simply noise-no matter how it is generated.  It doesn't matter if it is 1 watt or 10,000 watts or a drill or a air hose.
Logged
A complex question is easily answered by a simple-easy to understand WRONG answer!

Ivan Beaver
Danley Sound Labs

PHYSICS- NOT FADS!

Craig Hauber

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 597
  • Mondak Sound Design - Plentywood MT/Grenora ND
Re: Community S-218s? Any experience with it?
« Reply #18 on: January 06, 2013, 01:11:38 pm »

OSHA doesn't care about wattage-or sinewaves or even loudspeakers for that matter.

On the noise side of their "concerns", it is simply noise-no matter how it is generated.  It doesn't matter if it is 1 watt or 10,000 watts or a drill or a air hose.

Then how come they aren't cracking-down on nightclubs in this country?  They are continuous no-dynamics techno music that can probably be equated to a continuous machine/manufacturing type noise.  The staff at these place do receive damaging levels!
I ran one for a while and it was a constant battle to keep levels down and I wondered why it was such a fight to convince people that quality not quantity was our goal -until I checked out every other club in town and they were just screaming loud.

They took away smoking in bars predominantly for the benefit of the staff, wait until the authorities start regulating our volume levels from a health standpoint! (not just the because the neighbors complaining)

The manufacturers aren't helping with ads like the one I attached (from Bassmaxx's site) -I know those RTA's can easily be out-of-cal, but to even desire, strive to, and brag about wanting to expose anyone in a small room to 130dB or higher continuously is just wrong!
(I guess it's no different than people doing drugs or booze until the point of death or damage -except I'm I don't want to be the pusher!)

Logged
Craig Hauber
Mondak Sound Design
-Live PA
-Installs
-Theatre

Ivan Beaver

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 8885
  • Atlanta GA
Re: Community S-218s? Any experience with it?
« Reply #19 on: January 06, 2013, 02:27:56 pm »

Then how come they aren't cracking-down on nightclubs in this country?  They are continuous no-dynamics techno music that can probably be equated to a continuous machine/manufacturing type noise.  The staff at these place do receive damaging levels!
I ran one for a while and it was a constant battle to keep levels down and I wondered why it was such a fight to convince people that quality not quantity was our goal -until I checked out every other club in town and they were just screaming loud.

They took away smoking in bars predominantly for the benefit of the staff, wait until the authorities start regulating our volume levels from a health standpoint! (not just the because the neighbors complaining)

The manufacturers aren't helping with ads like the one I attached (from Bassmaxx's site) -I know those RTA's can easily be out-of-cal, but to even desire, strive to, and brag about wanting to expose anyone in a small room to 130dB or higher continuously is just wrong!
(I guess it's no different than people doing drugs or booze until the point of death or damage -except I'm I don't want to be the pusher!)
Whenever the lawyers get a hold of a ear damage case and win-the flood gates are going to be opened.  Like a ear doctors daughter who start to develop ear damage because she goes to a loud club.

Then I can see the daytime lawyer ads now-"does your child have hearing damage from going to loud clubs?  call us."

You are walking down the street and see a lawyer and an IRS agent drowning in the river. You can only save one.  So do you sit down and read the paper-or go to lunch?
Logged
A complex question is easily answered by a simple-easy to understand WRONG answer!

Ivan Beaver
Danley Sound Labs

PHYSICS- NOT FADS!

ProSoundWeb Community

Re: Community S-218s? Any experience with it?
« Reply #19 on: January 06, 2013, 02:27:56 pm »


Pages: 1 [2] 3 4   Go Up
 



Page created in 0.109 seconds with 20 queries.