Measurements and conclusion
Contents
We can be fairly brief: the Wharfedale Diamond 12.2 doesn’t perform well in our measurements. The frequency response is pretty much okay, but where it goes wrong is distortion. We see a huge peak around 190 Hz (1.8%) and then another one around 560 Hz (3%). These are nasty, because the one at 560 Hz is at 3% and also full in the vocal range. Then another hump between 2000 and 3000 Hz. That one is just above 1%.
Double check…
We measured several times and once again we took another bookshelf (our Sonus Faber Lumina’s) to see if something else was wrong. But unfortunately for Wharfedale these measurements are correct. It is – to put it mildly – not to something to be proud of.
We’re guessing it has to do with the components in the filter, because the filter also measures a bit strange. The spikes in impedance are not even crazy: almost all bass reflex speakers have them. However, we find the Q of the inductance rather odd. It peaks right around those spots when you recalculate the harmonics. (Just divide the values of the induction Q by 2). Perhaps clumsy layout of the filter? Component quality? Who will say…