Audeze LCD-X headphones Measurements

Sidebar 3: Measurements

I don't measure headphone acoustic responses, as this requires a dummy-head-and-microphone system: see Keith Howard's article on this subject in the August 2008 issue. In addition, as Keith wrote, deciding what, precisely, is the optimal frequency response for a pair of headphones is neither obvious nor trivial.

I used Stereophile's vintage Audio Precision System One to measure the Audeze LCD-X's impedance and electrical phase (fig.1). The solid trace in this graph shows the impedance magnitude with the headphones mounted on my head facing my ears. The impedance in the audioband is close to 22 ohms. The electrical phase angle is also close to 0° across the audioband.

214audeze.fig1.jpg

Fig.1 Audeze LCD-X, electrical impedance (solid) and phase (dashed) mounted against JA's head and ears (5 ohms/vertical div.).

Other than a small peak at 4kHz, which at first I thought was due to my ear-canal resonance—until I noted that it was also present in a free-space measurement—the LCD-X's impedance was commendably constant with frequency. The headphone's frequency response will not alter with frequency when driven by a source with a high output impedance, like my Astell&Kern player. However, this relatively low impedance will mean that the Audeze headphones will work best when driven by an amplifier with a low output impedance. My HeadRoom BlockHead, which has an impedance of less than 1 ohm, was perfect in this this respect.—John Atkinson

COMPANY INFO
Audeze LLC,
10725 Ellis Avenue, Unit E
Fountain Valley, CA 92708
(657) 464-7029
ARTICLE CONTENTS

COMMENTS
Regadude's picture

John! John! John! What has come over you?! A few days ago, you posted a great article about the dangers of over compression:

http://www.stereophile.com/content/squeezing-music-0#comment-536628

And here you are testing 1700$ headphones, with (among other things) an iPod and lossy mp3 files. JOOOHHNN!!!!!!!!!!!!!!!!!

What happened to "source first"? What happended to at least having decent media? Geez, I could understand digital files that are at least CD quality. I could understand listening to such files on a decent streamer. But, mp3s on an iPod?!?!?!??!

I am not angry at you John. Just so very disappointed...

If Michael Fremer reads this, please Mikey, take John out for a drink. Give him a good "talking to". Set him straight and give him sh*t if you have to. Maybe then John can review these glorious headphones with a real amp and a good quality source (how about some vinyl?).

I need a drink... sad

John Atkinson's picture

RegaDude wrote:
A few days ago, you posted a great article about the dangers of over compression:

http://www.stereophile.com/content/squeezing-music-0#comment-536628

And here you are testing 1700$ headphones, with (among other things) an iPod and lossy mp3 files. JOOOHHNN!!!!!!!!!!!!!!!!!

You're confusing the two different uses of the word "compression." As I thought I had clarified in the footnote to my artlcle that you linked to, the unmusical "squeezing" referred to analog compression, raising the level of the quiet passges to be as loud as the loud passages. I was not referring to the use of lossy codecs to reduce file size. It is quite possible both to have an MP3 of uncompressed music and a lossless file of compressed music.

I didn't use an iPod to audition the Audeze headphones. But what's wrong with using an iPod?

John Atkinson

Editor, Stereophile

Regadude's picture

Ok, so you didn't use an ipod to review the Audeze. My mistake. I do fail to understand why an ipod would be mentionned in a review of high end equipment.

What's wrong with an ipod? Nothing, if it's used in the right context. I wear my ipod when and only when I jog. I jog with it in rain, snow and freezing temperatures, When I get home from my jog, I throw the weather beaten, sweat covered thing in the back of my closet. Then the real system comes on... Ipods have no place in a serious system. Ipods have no place in an entry level audiophile system. 

An ipod sounds like crap even in Mikey's megabuck system:

http://gizmodo.com/5213042/why-we-need-audiophiles

John Atkinson's picture

Regadude wrote:
Ipods have no place in a serious system. Ipods have no place in an entry level audiophile system. 

An ipod sounds like crap even in Mikey's megabuck system:

http://gizmodo.com/5213042/why-we-need-audiophiles

I understood that Mikey was referring to MP3 files in the linked article, not iPods in general. The two are not related. Yes, while you can play lossy-compressed MP3 and AAC files on an iPod, for a decade now iPods can play both lossless files and uncompressed WAV/AIFF files. As such, an iPod is a perfectly legitimate source of CD-resolution music.

John Atkinson

Editor, Stereophile

arve's picture

Stereophile's sister magazine InnerFidelity has a full set of measurements here: 

http://www.innerfidelity.com/images/AudezeLCDXSample3.pdf

Those not familiar with headphone measurements should also read read http://www.innerfidelity.com/content/headphone-measurements-explained-square-wave-response

ElementAudio's picture

Instead of battling for headphones, we should be concerned with how the music is being mixed for headphones. Stereo mixes don't translate, unless we use the Duplex Panner from Element Audio Group.

The Duplex Panner allows users to generate enhanced stereo mixes that create out-of-the head, spatial, and realistic experiences on headphones but without deteriorating stereo playback. Finally a method that bridges the gap between headphones and speaker playback. One mix, two amazing experiences!!

Check out the AES award-winning plugin the Duplex Panner here and become part of a new era in music production by contributing in the Kickstarter campaign !

With your contribution on the Kickstarter campaign , I will be able to fully develop this product to include suggested presets, have a fully functional mono/stereo mode, and most notably be the first all-in-one master bus panner where you can pan all your sources rather than scrolling through all your tracks. Please visit the Kickstarter campaign for more info and don't miss out on the future of music.

X