Four "monitor" speakers
This is an interesting one. I've looked a bit further into this and for your interest attach a picture of three "pro" monitors (A, B, C) and one "domestic" monitor (D) measured under controlled conditions. D was measured using a different audio test set, but I've made sure the vertical/horizontal scales are directly comparable with the others. (I could possibly have exported D and imported into the later A-B-C measuring system but that needs some time).
What do you make of these? These were measured three years ago and as far as I know, A and B are current models. A is what I'll call a 'Euromonitor'. B is the manifestation of a particular approach to speaker system design. C .... any thoughts? And D? Which one would be expected to give the 'most natural' sound? And if you were a professional sound engineer, based on these curves alone, which one would you have most confidence in as telling you what is really going on in your mix? And which would be likely to give you most or least listening fatigue?
As you can see there are, even now 2011 some eighty or so years after recognisable loudspeakers appeared, very big measurable differences between speakers. Let alone sonic differences.
No competitive brand names will be revealed.
NOTE: Ignore the exact dB markings on the left scale. dBs can be usefully relative (as well as absolute) measurements, like percentages and speaker designers tend not to need to know what a sensitivity figure is, for example, 85.5dB at some frequency. We need to know by how much it varies across the audio band. So, although the left dB scale axis is exactly comparable, you cannot deduce anything from reading the absolute numbers: we've just laid these four speakers out on the page neatly, not in sensitivity ranking.
Alan A. Shaw
Harbeth Audio UK