Default GH4 sound: typical Grado peak at 2khz, followed by raised treble between 4k-9khz. Slight bass bump at 100hz but rolls off very rapidly below 50hz, so there’s little sub-bass. This gives bass a kind of ‘bouncy’ character.
Let’s then get into pad rolling (measured with legacy KB006X pinnae):
The original pads on the GH4 is the most typically used Grado pads called the L-Cush pads (supra-aural). First we have a set of Chinese L-Cush pads I found randomly on Taobao. Not bad eh? More bass and gentler 2khz peak. Mid-treble remains about the same though, just slightly lower by about 2-3db at some spots.
Next let’s get into larger circumaural pads.
Swapping to original G-cush (larger bowl-shaped pads), the 2khz peak is significantly lowerd. This pattern is the same for both the original Grado G-Cush and the Chinese third-party made G-cush. Difference between these two is mainly bass – the Chinese made ones are much softer and more spongy than the Grado ones, resulting in more bass. IMO this helps to balance the hot treble. Also the Chinese ones are smoother around 3khz.
More pictures and impressions will follow – too late today.
Upshot: softer, lower-density sponge pads help to add bass and lower treble peaks on the Grado GH4.
the unheard of headphone lab 