ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 2 [3] 4 5   Go Down

Author Topic: How loud is 115 dB A-weighted?  (Read 5735 times)

Tim McCulloch

  • SR Forums
  • Hero Member
  • *
  • Offline Offline
  • Posts: 23773
  • Wichita, Kansas USA
Re: How loud is 115 dB A-weighted?
« Reply #20 on: June 12, 2022, 12:58:55 PM »

At some point we realize that most of the numeric "specifications" are bullshit.  Take a look at the acceptable systems list and compare those one number specs and you'll find a decent-size gap.  If the rider says VerTec/VTX/K2/d&b J/ etc, I presume whoever wrote it decided they can successfully do the acts show on those rigs regardless of any spec sheet differences.

What I've found works best is to phone or email the FOH or PM and ask what's real and what's Memorex.

As for BEs flogging the rig... If a BE stays out of protective limiting, the BE will never hear from me during the show unless I'm needed to check fill balances or verify operation of something.  If the BE hits limits on brief peaks, ditto.  Sustained limiting (over 10 seconds or so) and I'll let the BE know the rig is in protect and give the opportunity to deftly correct that.  How I react if that is not done depends on how deep into protect (and for how long), and how much time remains in the set.
Logged
"If you're passing on your way, from Palm Springs to L.A., Give a wave to good ol' Dave, Say hello to progress and goodbye to the Moonlight Motor Inn." - Steve Spurgin, Moonlight Motor Inn

Ivan Beaver

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 9538
  • Atlanta GA
Re: How loud is 115 dB A-weighted?
« Reply #21 on: June 13, 2022, 10:19:22 AM »


As for BEs flogging the rig... If a BE stays out of protective limiting, the BE will never hear from me during the show unless I'm needed to check fill balances or verify operation of something.  If the BE hits limits on brief peaks, ditto.  Sustained limiting (over 10 seconds or so) and I'll let the BE know the rig is in protect and give the opportunity to deftly correct that.  How I react if that is not done depends on how deep into protect (and for how long), and how much time remains in the set.
And the attitude of the operator.

I have known "operators", who, if they are not happy with the system will try to do anything to do as much damage to it as possible.

No matter what their band sounded like (in some cases it really didn't matter).  The sound system was all about THEIR satisfaction, not the paying audience.  They just wanted toys to play with that they did not have to pay the repair bill for.

Sad, but true.

In some cases, their reputation preceded them, so the venues would take extra precautions to protect the gear, yes, by limiting the possible performance.

So the end result is the audience gets lessor performance, simply because of the attitude of the operator.

Notice I did not use the term "engineer".  Most operators are no where near what might be called an "engineer".  They are just knob twisters who have no real idea what is actually happens.  But I'm not going there-------------
Logged
A complex question is easily answered by a simple-easy to understand WRONG answer!

Ivan Beaver
Danley Sound Labs

PHYSICS- NOT FADS!

Ed Hall

  • Classic LAB
  • Sr. Member
  • *
  • Offline Offline
  • Posts: 260
  • Lansdale, PA
Re: How loud is 115 dB A-weighted?
« Reply #22 on: June 24, 2022, 09:53:37 PM »

Notice I did not use the term "engineer".  Most operators are no where near what might be called an "engineer".  They are just knob twisters who have no real idea what is actually happens.  But I'm not going there-------------

But that is why I come here. So I am more than an uninformed knob turner. I want to know the why behind the what!
Logged
I can't change reality just because you don't like it!

Mario Pollio

  • Full Member
  • ***
  • Offline Offline
  • Posts: 116
Re: How loud is 115 dB A-weighted?
« Reply #23 on: August 16, 2022, 02:10:08 PM »

Code: [Select]
I understand the requirement for headroom to ensure the gear can get through a gig easily, but what is the purpose of actually running the system so loud that it’s not enjoyable anymore? I’m not an old fart saying loud isn’t fun, but it gets to a point where it’s not fun anymore and nobody could possibly be enjoying themselves.

This is about as loud as I can possibly stand. Couldn’t imagine sitting through a 2-3 hour show at these levels. This is A weighted, slow, and it was absolutely ridiculous. 115 db A weighted slow at the furthest seat would turn an arena into a giant torture chamber.

Also attached C weighted for comparison
Logged

Don T. Williams

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1069
  • Midas Pro 1 & 2, M32, dbTech T12, T8, S30, DM12
    • Q Systems Music & Sound
Re: How loud is 115 dB A-weighted?
« Reply #24 on: August 16, 2022, 04:40:31 PM »

Only 115dB?  I have a rider that asks for 125dB 20Hz to 20KHz everywhere in the house.  The promoter really had trouble understanding why we would not bid the show. We had worked an event with that group a few years earlier (without getting a tech rider), and they continuously pushed the system to REALY STUPID LOUD and we continuously ask the "engineer" to please turn it down.  Never again!
Logged

Mario Pollio

  • Full Member
  • ***
  • Offline Offline
  • Posts: 116
Re: How loud is 115 dB A-weighted?
« Reply #25 on: August 16, 2022, 05:52:05 PM »

Only 115dB?  I have a rider that asks for 125dB 20Hz to 20KHz everywhere in the house.  The promoter really had trouble understanding why we would not bid the show. We had worked an event with that group a few years earlier (without getting a tech rider), and they continuously pushed the system to REALY STUPID LOUD and we continuously ask the "engineer" to please turn it down.  Never again!

They must want people to run out holding their ears
Logged

Ivan Beaver

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 9538
  • Atlanta GA
Re: How loud is 115 dB A-weighted?
« Reply #26 on: August 16, 2022, 08:10:33 PM »

Code: [Select]
I understand the requirement for headroom to ensure the gear can get through a gig easily, but what is the purpose of actually running the system so loud that it’s not enjoyable anymore? I’m not an old fart saying loud isn’t fun, but it gets to a point where it’s not fun anymore and nobody could possibly be enjoying themselves.

This is about as loud as I can possibly stand. Couldn’t imagine sitting through a 2-3 hour show at these levels. This is A weighted, slow, and it was absolutely ridiculous. 115 db A weighted slow at the furthest seat would turn an arena into a giant torture chamber.

Also attached C weighted for comparison
I would be cautious of any levels over 100dB (whatever weighting) on a phone.

The electronics might be fine, but the mic used and its capability is in question.
Logged
A complex question is easily answered by a simple-easy to understand WRONG answer!

Ivan Beaver
Danley Sound Labs

PHYSICS- NOT FADS!

Mario Pollio

  • Full Member
  • ***
  • Offline Offline
  • Posts: 116
Re: How loud is 115 dB A-weighted?
« Reply #27 on: August 16, 2022, 08:22:23 PM »

I would be cautious of any levels over 100dB (whatever weighting) on a phone.

The electronics might be fine, but the mic used and its capability is in question.

I tested it against a Radio Shack SPL meter and REW with a UMIK-1. It’s surprisingly accurate. Louder volumes tend to show a smaller number on the phone, but it’s still within a db or two.
Logged

Michael Lawrence

  • Full Member
  • ***
  • Offline Offline
  • Posts: 172
Re: How loud is 115 dB A-weighted?
« Reply #28 on: August 16, 2022, 09:02:05 PM »

I would be cautious of any levels over 100dB (whatever weighting) on a phone.

The electronics might be fine, but the mic used and its capability is in question.

I enjoy this topic.

An analysis of a large number of concert SPL logfiles reveals that max Peak C levels are typically 32-35 dB above the average A-Slow SPL, which takes into account both crest factor and the C-A of the material. At typical concert levels (A Slow L50 around 99 - 100 dB), we can expect to see max Peak C levels in the mid-130's.

The MEMS elements used in smartphones are simply not designed to withstand such SPL, and many popular measurement mics aren't either.

Our Smaart Gear Choices Guide has some information to consider when choosing measurement microphones and interfaces for concert-level SPL measurement.

Some data: https://blogs.cdc.gov/niosh-science-blog/2014/04/09/sound-apps/

https://asa.scitation.org/doi/full/10.1121/1.4964639

The attached figure, which comes from the second link, shows very wide error bars for internal microphones (and between apps). As for using a Radio Shack meter as a reference, that's sort of a "turtles all the way down" situation. If you are afforded the opportunity, put 4 or 5 of them next to each other and observe the results - you will have more questions than answers.

The fun thing about those units is that they have a mic output on the side, which means you can connect it to a measurement rig and do a mic compare vs a measurement rig.

Due to the size of the diaphragm, they exhibit a very large hi-mid peak on-axis to a sound source which goes away with a change in orientation, despite the claims of the spec sheet.

Mobile devices (without external microphones) and "party favor" handheld meters are certainly entertaining and are useful for relative measurements (is the show the same level as yesterday?) but I certainly would not use them to make any determinations in situations where the displayed value needs to be meaningful.
Logged
Lead Instructor / Smaart SPL Product Manager - Rational Acoustics
Technical Editor - ProSoundWeb.com
Freelance Systems Engineer

Mario Pollio

  • Full Member
  • ***
  • Offline Offline
  • Posts: 116
Re: How loud is 115 dB A-weighted?
« Reply #29 on: August 17, 2022, 09:03:33 AM »

I enjoy this topic.

An analysis of a large number of concert SPL logfiles reveals that max Peak C levels are typically 32-35 dB above the average A-Slow SPL, which takes into account both crest factor and the C-A of the material. At typical concert levels (A Slow L50 around 99 - 100 dB), we can expect to see max Peak C levels in the mid-130's.

The MEMS elements used in smartphones are simply not designed to withstand such SPL, and many popular measurement mics aren't either.

Our Smaart Gear Choices Guide has some information to consider when choosing measurement microphones and interfaces for concert-level SPL measurement.

Some data: https://blogs.cdc.gov/niosh-science-blog/2014/04/09/sound-apps/

https://asa.scitation.org/doi/full/10.1121/1.4964639

The attached figure, which comes from the second link, shows very wide error bars for internal microphones (and between apps). As for using a Radio Shack meter as a reference, that's sort of a "turtles all the way down" situation. If you are afforded the opportunity, put 4 or 5 of them next to each other and observe the results - you will have more questions than answers.

The fun thing about those units is that they have a mic output on the side, which means you can connect it to a measurement rig and do a mic compare vs a measurement rig.

Due to the size of the diaphragm, they exhibit a very large hi-mid peak on-axis to a sound source which goes away with a change in orientation, despite the claims of the spec sheet.

Mobile devices (without external microphones) and "party favor" handheld meters are certainly entertaining and are useful for relative measurements (is the show the same level as yesterday?) but I certainly would not use them to make any determinations in situations where the displayed value needs to be meaningful.

Very interesting. Between the UMIK, Radio Shack meter, app, and my poor ears, I was able to determine it was extremely effing loud lol. How accurate the actual number is, I’m not sure but it is as almost panic attack inducing.
Logged

ProSoundWeb Community

Re: How loud is 115 dB A-weighted?
« Reply #29 on: August 17, 2022, 09:03:33 AM »


Pages: 1 2 [3] 4 5   Go Up
 



Site Hosted By Ashdown Technologies, Inc.

Page created in 0.035 seconds with 22 queries.