ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  

Pages: 1 2 [3] 4   Go Down

Author Topic: Speaker measurement  (Read 11346 times)

Tim McCulloch

  • SR Forums
  • Hero Member
  • *
  • Offline Offline
  • Posts: 21499
  • Wichita, Kansas USA
Re: Speaker measurement
« Reply #20 on: February 15, 2016, 07:19:35 pm »

Hi Ben-

I'm not a loudspeaker measurement guru other than to measure the various subsystems in situ and attempt to align them together, but my experience in learning how to make valid measurements then led to learning how to interpret those measurements.  These processes are sequential and interdependent.

I took my first Smaart class in 2004, came home and proceeded to make hundreds of invalid measurements.  I discovered they were invalid when the applied correction didn't actually correct anything and sometimes made things worse.  Once I could consistently make valid measurements it took another several months of working, and now years of experimenting, that I feel I have a solid grip on interpreting my measurements.

What Ivan was suggesting is that possession and use of appropriate software provides no certainty of a valid or useful outcome especially for someone just beginning.

Logged
"Practicing an art, no matter how well or badly, is a way to make your soul grow, for heaven's sake. Sing in the shower. Dance to the radio. Tell stories. Write a poem to a friend, even a lousy poem. Do it as well as you possible can. You will get an enormous reward. You will have created something."  - Kurt Vonnegut

Cailen Waddell

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1428
Re: Speaker measurement
« Reply #21 on: February 15, 2016, 08:04:15 pm »


Hi Ben-

I'm not a loudspeaker measurement guru other than to measure the various subsystems in situ and attempt to align them together, but my experience in learning how to make valid measurements then led to learning how to interpret those measurements.  These processes are sequential and interdependent.

I took my first Smaart class in 2004, came home and proceeded to make hundreds of invalid measurements.  I discovered they were invalid when the applied correction didn't actually correct anything and sometimes made things worse.  Once I could consistently make valid measurements it took another several months of working, and now years of experimenting, that I feel I have a solid grip on interpreting my measurements.

What Ivan was suggesting is that possession and use of appropriate software provides no certainty of a valid or useful outcome especially for someone just beginning.

BUT don't let that be discouraging.  Instead take that and start making measurements knowing you may be completely wrong and it's ok if you can learn and grow from it.


Sent from my iPhone using Tapatalk
Logged

Ivan Beaver

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 9045
  • Atlanta GA
Re: Speaker measurement
« Reply #22 on: February 15, 2016, 09:10:09 pm »

Hi Ben-

I'm not a loudspeaker measurement guru other than to measure the various subsystems in situ and attempt to align them together, but my experience in learning how to make valid measurements then led to learning how to interpret those measurements.  These processes are sequential and interdependent.

I took my first Smaart class in 2004, came home and proceeded to make hundreds of invalid measurements.  I discovered they were invalid when the applied correction didn't actually correct anything and sometimes made things worse.  Once I could consistently make valid measurements it took another several months of working, and now years of experimenting, that I feel I have a solid grip on interpreting my measurements.

What Ivan was suggesting is that possession and use of appropriate software provides no certainty of a valid or useful outcome especially for someone just beginning.
Agreed.

We learn from doing things WRONG.  And trying to figure out what went wrong and learning from the mistakes.

Now if you don't question what you are measuring and start to wonder "Why is that happening" then you won't learn.

But sharing and learning from others mistakes is also a good way.

The hardest thing to get across to people getting started in measurements is "Just because a wiggly line is on the screen DOES NOT mean it is VALID.".

It may be "correct" for the position and parameters involved-but that DOES NOT make it valid or useful.

Learning to "read between the lines" can be very useful.

And if something does not look right (based on other information available) it probably isn't.

It can be a long road and is not something you understand quickly.

But it DOES give you a better understanding of what you can and often MORE IMPORTANTLY-CANNOT do anything about.

Sometimes (lots of times) it is far better NOT to try to eq that dip in the response.

Yes it may "appear" on the screen, and you may "appear" to fix it, but try changing the resolution and you may realize all you did was make a non fixable problem worse in freq that are higher and lower in freq.  So trying to fix a non audible problem has now resulted in a large hump in the freq response-NOT the flat response as first shown on the screen.

Reflections are a typical example.

And if you DID manage to fix it-AT ONE LOCATION-everywhere else it is worse.

Is THAT really what you were after? NO.

Sorry to rant.

Logged
A complex question is easily answered by a simple-easy to understand WRONG answer!

Ivan Beaver
Danley Sound Labs

PHYSICS- NOT FADS!

Jeff Bankston

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2384
Re: Speaker measurement
« Reply #23 on: February 20, 2016, 08:32:15 pm »

The AKG C460B/CK61ULS mics are flat from 20-20k. You can find them on ebay for $300.00 to $400.00. they are exelent for hihats and overheads when you are done measuring.
Logged

Ivan Beaver

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 9045
  • Atlanta GA
Re: Speaker measurement
« Reply #24 on: February 20, 2016, 09:45:00 pm »

The AKG C460B/CK61ULS mics are flat from 20-20k. You can find them on ebay for $300.00 to $400.00. they are exelent for hihats and overheads when you are done measuring.
You generally want on OMNI mic for measurement-not any sort of directional mic.

There are a few cases where directional mics can help-but in general you want omni
Logged
A complex question is easily answered by a simple-easy to understand WRONG answer!

Ivan Beaver
Danley Sound Labs

PHYSICS- NOT FADS!

Jeff Bankston

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2384
Re: Speaker measurement
« Reply #25 on: February 20, 2016, 11:11:30 pm »

You generally want on OMNI mic for measurement-not any sort of directional mic.

There are a few cases where directional mics can help-but in general you want omni
they make an omni capsule for the AKG C460B. the CK62-ULS omni capsule.
Logged

David Sturzenbecher

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1712
  • So. Dak.
    • Sturz Audio
Re: Speaker measurement
« Reply #26 on: February 21, 2016, 12:48:45 am »


they make an omni capsule for the AKG C460B. the CK62-ULS omni capsule.

That capsule is over 3/4" in diameter. I can't image it being truly omni at high frequencies.  There is a reason why the reference microphones have small capsule diameters.


Sent from my iPhone using Tapatalk
Logged
Audio Systems Design Engineer
Daktronics, Inc.
CTS-D, CTS-I
AES Full Member

Merlijn van Veen

  • Moderator
  • Sr. Member
  • *****
  • Offline Offline
  • Posts: 309
    • www.merlijnvanveen.nl
Re: Speaker measurement
« Reply #27 on: February 21, 2016, 01:58:30 am »


That capsule is over 3/4" in diameter. I can't image it being truly omni at high frequencies.  There is a reason why the reference microphones have small capsule diameters.


Sent from my iPhone using Tapatalk

+1

My DPA 4091 with 0.21" capsule is omnidirectional up to 5 kHz and then it exhibits as much as 3 dB of directivity.


Verzonden vanaf mijn iPad met Tapatalk

Jeff Bankston

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 2384
Re: Speaker measurement
« Reply #28 on: February 21, 2016, 02:49:09 am »

That capsule is over 3/4" in diameter. I can't image it being truly omni at high frequencies.  There is a reason why the reference microphones have small capsule diameters.


Sent from my iPhone using Tapatalk
the mics and capsules are 21mm in diameter. A C460B with  one capsule cost $999.00 new. Not a cheap mic. I checked on ebay earlier and they were for about 400 and up used. the C480B replaced the C460B and doesnt have a transformer. Here is a foto I just took. why would a smaller diameter be better ?
Logged

William Schnake

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 591
    • Schnake Sound & Light
Re: Speaker measurement
« Reply #29 on: February 21, 2016, 08:18:19 am »

It's just like doing shows.

You can do a hundred shows and everything goes just fine.  But you learn very little.

Then there is that one that all hell breaks loose and all kinds of totally unrelated things go wrong.

Yes it is a nightmare (at the time), but you LEARN a whole lot from the experience.
Ivan, are you referring to my first outing with the former lead singer of Poison?  This is absolutely dead on about that experience.  OK back to talking about speakers now.

Bill
Logged
Bill Schnake - Owner Schnake Sound & Light

Avid/Crown/EAW/EV/Midas/RCF/Shure/Yamaha

schnakesound.com

ProSoundWeb Community

Re: Speaker measurement
« Reply #29 on: February 21, 2016, 08:18:19 am »


Pages: 1 2 [3] 4   Go Up
 



Page created in 0.036 seconds with 24 queries.