Originally Posted by jaddie
The distortion graph shows frequency distribution of the harmonics, which is actually fairly important. They don't usually plot THD vs frequency for headphones, that's true, but distortion plots over about 7 or 8 KHz are fairly meaningless anyway.
We're are talking about the distortion product graph now, yes?
Why the concern over the square wave graphs? What do you think they are telling you?
The 50 Hz sq wave seem to be a reasonable tell for whether or not a headphone will be able to produce punchy as opposed to boomy bass:
The headphone's ability to maintain a constant pressure for the length of the flat top and bottom is a measure of how well it can reproduce low frequency notes. This is very difficult as the driver is small with a limited excursion and the earcup is fairly leaky and lets pressure out easily.
In no case we've observed has a headphone been able to keep a truly flat line; ear canal headphones can come the closest as they only have a small, sealed volume of air in the ear canal to compress. But the ability for the headphones to create a straight line at the top and bottom, even if it's tilted will indicate coherent performance in the lows.
From the headphones I have, the Superlux668B, which is ok in every way except its ability to do high attack bass (making it pretty unsatisfying for rock, because the drums lose it):
And the HD25-1-ii, which is much better:
Otoh, a good 50Hz sq wave doesn't seem to guarantee punchy bass, otherwise my Ety HF5s would sound much better to me:
..So my ***extremely*** tentative hypothesis is that a good 50Hz sq wave result is necessary but not sufficient for well defined bass.
Maybe I have the initials wrong? The waterfall graph for frequency response over time?
Edited by scuttle - 2/12/13 at 1:46am