Re: Frequency Response/Contour EQ in full range systems.
Charlie Hughes' comments about getting different results when measuring in different acoustic environments, at different locations, or with different time windows are apposite.
Notwithstanding the point about direct field versus power response, I'm in the "flat response" camp when it comes to system voicing for general use (in general, indoors, measured far field but close to the source, with no time windowing), maybe allowing a few dB bump below 100Hz (if speech intelligibility matters and routing to the subs can't be controlled per channel, then no more than a few dB). Some styles of music have certainly come to be associated with exaggerated bass, but I'd rather add that emphasis to channels where it's appropriate than have it applied to everything reproduced by the system.
With regard to time windowing, some measurement systems enforce a time window by their nature, some don't support one at all, and some (like Smaart) make the facility available at the user's discretion. In my experience of the sorts of system-tweaking I think we're talking about, few people using Smaart employ a time window so the magnitude response ends up being the same as an "RTA" analysis (which is to say, the magnitude of the sound pressure field at the measurement location). The time window embodied by the FT process itself isn't the same thing.
I'm still quite attached to my handheld RTA. Its usefulness stems from the ability to quickly measure an average response whilst moving across a loudspeaker's area of coverage. Aberrations from specific reflections are averaged out, though one still needs a brain to spot a floor reflection.
I don't really understand the notion that "flat sounds bad", though it obviously depends entirely on what is being measured and in what way. "Flat" sounds like ... whatever the source sounds like. I'm yet to hear anyone complain about a mixer or power amplifier for exhibiting flat response.
Nick
