ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  
Pages: 1 ... 9 10 [11]   Go Down

Author Topic: JBL SRX718 - Basic Distortion Measurements  (Read 38796 times)

Jeff Permanian

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 313
    • http://www.JTRspeakers.com
Re: JBL SRX718 - Basic Distortion Measurements
« Reply #100 on: January 20, 2011, 07:35:59 pm »

Phil Lewandowski wrote on Wed, 19 January 2011 21:30

In running the rig in real gigs, I have found that I feel that a pair of SRX718 had a bit more output than a pair of '08/'09 Growlers and that would be very impressive if the SRX718 were really 5dB less efficient.


Must be perception because your measurements show the Growler 1db louder average 50hz and above.
Logged

Phil Lewandowski

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1101
Re: JBL SRX718 - Basic Distortion Measurements
« Reply #101 on: January 21, 2011, 08:27:22 am »

Jeff Permanian wrote on Thu, 20 January 2011 19:35

Phil Lewandowski wrote on Wed, 19 January 2011 21:30

In running the rig in real gigs, I have found that I feel that a pair of SRX718 had a bit more output than a pair of '08/'09 Growlers and that would be very impressive if the SRX718 were really 5dB less efficient.


Must be perception because your measurements show the Growler 1db louder average 50hz and above.



Actually that could very much be the case.  Especially since it is a direct radiator vs. A horn loaded.  And you could definitely hear more harmonic distortion in the SRX718 in my tests.

It was just a touch more punch at higher volumes, just a touch nothing super crazy. And it could very well be added harmonic distortion.


Take care,

Phil
Logged
"It is good to be Alive!"

L and L: Live Sound
landllivesound.com

Greg Cameron

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1832
    • http://www.cameronproaudio.com
Re: JBL SRX718 - Basic Distortion Measurements
« Reply #102 on: January 21, 2011, 12:00:43 pm »

Phil Lewandowski wrote on Fri, 21 January 2011 05:27

Jeff Permanian wrote on Thu, 20 January 2011 19:35

Phil Lewandowski wrote on Wed, 19 January 2011 21:30

In running the rig in real gigs, I have found that I feel that a pair of SRX718 had a bit more output than a pair of '08/'09 Growlers and that would be very impressive if the SRX718 were really 5dB less efficient.


Must be perception because your measurements show the Growler 1db louder average 50hz and above.



Actually that could very much be the case.  Especially since it is a direct radiator vs. A horn loaded.  And you could definitely hear more harmonic distortion in the SRX718 in my tests.

It was just a touch more punch at higher volumes, just a touch nothing super crazy. And it could very well be added harmonic distortion.


This could also be related to a point that Art brought up a while back: subs that go down lower tend to give the perception of greater output, all things being equal. Just going off the spec sheet, Jeff's box has a -3dB point of 41Hz vs. 34Hz on the JBL box. The JBL box shows a -10dB point of 31Hz which means it's low cut-off is likely around the 28Hz range before it unloads. I don't know what the cut-off is on the Growler, but I'm guessing it falls of pretty fast below 40Hz.

Greg
Logged
Cameron Pro Audio.

"Procrastinators of the world - contemplate uniting!"

Phil Lewandowski

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 1101
Re: JBL SRX718 - Basic Distortion Measurements
« Reply #103 on: January 21, 2011, 03:15:21 pm »

Greg Cameron wrote on Fri, 21 January 2011 12:00

Phil Lewandowski wrote on Fri, 21 January 2011 05:27

Jeff Permanian wrote on Thu, 20 January 2011 19:35

Phil Lewandowski wrote on Wed, 19 January 2011 21:30

In running the rig in real gigs, I have found that I feel that a pair of SRX718 had a bit more output than a pair of '08/'09 Growlers and that would be very impressive if the SRX718 were really 5dB less efficient.


Must be perception because your measurements show the Growler 1db louder average 50hz and above.



Actually that could very much be the case.  Especially since it is a direct radiator vs. A horn loaded.  And you could definitely hear more harmonic distortion in the SRX718 in my tests.

It was just a touch more punch at higher volumes, just a touch nothing super crazy. And it could very well be added harmonic distortion.


This could also be related to a point that Art brought up a while back: subs that go down lower tend to give the perception of greater output, all things being equal. Just going off the spec sheet, Jeff's box has a -3dB point of 41Hz vs. 34Hz on the JBL box. The JBL box shows a -10dB point of 31Hz which means it's low cut-off is likely around the 28Hz range before it unloads. I don't know what the cut-off is on the Growler, but I'm guessing it falls of pretty fast below 40Hz.

Greg



Good point Greg,

The difference from my Smaart measurements of the Growler and SRX718 aren't huge but there is a slight advantage for the SRX718 from 30-40hz.

From 40hz and up they are pretty much neck to neck.  The SRX718 -3dB point in my 3 subs are all right about 43-44hz, which is almost exactly what my Growlers measured.

But below 40hz the Growler does fall like a rock and the SRX718 slopes off slightly slower.


At 35hz Growler is about 13dB down and the SRX718 is about 7-8dB down.  At 30hz the Growler is about 17dB down and SRX718 is about 11dB down.




Anywho, both great subs, so all this really gets into the nit-picking, even my comparing of a small difference of "punch."


Take Care,
Phil
Logged
"It is good to be Alive!"

L and L: Live Sound
landllivesound.com
Pages: 1 ... 9 10 [11]   Go Up
 

Page created in 0.116 seconds with 19 queries.