The link http://www.innerfidelity.com/images/AllGraphs.pdf is dead.
June Measurements Update

New headphones this month include:
- Many of the Ultrasone line.
- The new Shure SRH950.
- The Beyerdynamic DJX-1 (it's pretty good).
- Numerous Denon IEMs.
- Grado GR8.
- Spider Cables realvoice IEM
- Second measurements of Beyer's Tesla cans.
- And ... measurements of the latest LCD2 ... now with more highs!
- Log in or register to post comments



Hello,
Thanks for your website, it is very informative.
How do you explain the fact that you're measuring more highs with the LCD-2 ? New pads ?

Aside from the new highs, do you think that they image any better with the tilted pads?

m, nice, the second T5p did even worse THD+N wise :\
Good to see you also measured different impedance Beyer DT880s. For some reason a lot of the cans (denons, beyers, ultrasone) show near 10% distortion in the lower bass. What's the reason for that?

One primary source of harmonic distortion is found in driver excursion (due to mechanical nonlinearity + B field inhomogenity). Hence, anything that is not sealed airtight will show rising distortion at low frequencies due to increasing front-back cancellation. (Look at HD238s, open + smallish driver. Would love to see a burn-in experiment with those.) In some models you'll also see a THD peak accompanied by a FR dip, a sure sign of some cavity resonance occurring.
I would liken this to the behavior of an amplifier with output-stage-dominated distortion. It has to work harder when driving lower impedances, and distortion rises correspondingly. In fact, when using the concept of acoustic impedance there are a lot of parallels.
Not sure where those distortion peaks are coming from in the T1 and T5p. There shouldn't be any funny break-up modes around 1 kHz yet.
Never been an Ultrasone fan, and with the measurements (the FR graphs alone show evidence of a number of resonances) it's fairly clear why they are an acquired taste at best.
I'd say the awards for worst nonlinear distortion in a commercial headphone would have to go to ye olde Philips HP910 and Grado's RS2.