Building a Headphone Measurement Lab
Sep 13, 2010 at 6:05 PM Post #349 of 355

Tyll Hertsens

Garmentus Vulgaris & Headphoneus Supremus
Member of the Trade: Innerfidelity
Joined
Jun 22, 2001
Posts
4,102
Likes
1,185


Quote:
That's one looooooooong vacation. 


Yeah man.
L3000.gif
You have no idea. WAY more happened than I expected ... but that's another story for another place.
 
 
I just got back, and I'm going to spend this week getting reacquainted with my office and going through 2 1/2 months of emails. But next week you'll start seeing me more  .... around.
 
Good to be back.
 
Sep 13, 2010 at 6:24 PM Post #350 of 355

Roger Strummer

500+ Head-Fier
Joined
Mar 2, 2009
Posts
527
Likes
16


Quote:
Yeah man.
L3000.gif
You have no idea. WAY more happened than I expected ... but that's another story for another place.
 
 
I just got back, and I'm going to spend this week getting reacquainted with my office and going through 2 1/2 months of emails. But next week you'll start seeing me more  .... around.
 
Good to be back.


Great to see you're back!!! 
dt880smile.png
 
 
Sep 16, 2010 at 4:32 PM Post #351 of 355

sachu

Headphoneus Supremus
Joined
Oct 29, 2006
Posts
5,369
Likes
149
Hi Tyll,
 
was wondering if you were going to try and make the Seattle meet this October 2nd.
 
If not, i was wondering if you'd be kind enough to take some measurements of my Smeggy made Fostex thunerpants?
 
Sep 17, 2010 at 7:00 AM Post #352 of 355

xnor

Headphoneus Supremus
Joined
May 28, 2009
Posts
4,092
Likes
221
Dec 8, 2010 at 4:35 PM Post #354 of 355

MrGreen

Headphoneus Supremus
Joined
Oct 9, 2009
Posts
2,388
Likes
67
I wonder if Tyll (when he's around), Xnor or another member can tell me a few things about these measurements. Firstly, how is the raw frequency response data modified? By the looks to me, it might be based on Moller's diffuse field response? If not, do we have a name for and data of the modification applied?
 
Secondly, is the square wave response taking this into account or is it based on the raw output of the phone? I ask this because there is evidence of undershoot and ringing in the LCD-2, as well as a slope down to 0. Both of these suggest a. a boost in treble frequencies and b. insufficient bass response.
 
In the raw data for the frequency response of the LCD-2, it clearly shows a treble boost (which is necessary), relative to bass. However, in the compensated data it shows a clear roll-off.
 
Just looking for clarification, thanks.

If my suspicions are correct, is it possible to use a fourier transform to convert the compensated response to a square wave response?
 
Dec 8, 2010 at 5:07 PM Post #355 of 355

xnor

Headphoneus Supremus
Joined
May 28, 2009
Posts
4,092
Likes
221
I think that the compensation is based on measurements with the artificial head in a diffuse field. Somebody has written similar in this thread.
 
Your second question is very interesting. I too would like to know the answer.
 
 
But other than identifying some overshoot or ringing I don't see much use in the square wave measurements. I think you'd have to correct both the frequency and phase response first to make it more useful. And you need the same information for FFT matters.
 

Users who are viewing this thread

Top