Thats interesting. If a speaker has a flat response from 20Hz to 20kHz you should be hearing exactly what the what the recording engineers meant you to. I know that not all recordings are equal, but I doubt that these engineers mean for you to have a poor listening experience.
On top of that, those that have done the research in controlled blind a/b test conditions found that 'most people' like a flat response across the spectrum. I suspect that at least some of those that claim a speaker with a flat frequency response is harsh, have issues with room reflection that they blame on the speaker.
Not all speakers are equal and, no doubt, some speakers with a flat response are harsher than others. I don't yet understand the details of why that is, but from my listening experiences, I do know that there is more than flat response to speaker sound quality.
I've listened to several different speakers with a flat response and quite like the sound. Now, that was auditioning in sound rooms that were specifically set up to make the speakers sound their best, so it will be interesting to see what happens when I bring one of these speakers into my plaster covered concrete apartment.
Fred
I'm referring to the same listening tests I believe you're implying, those done by Floyd Toole. He determined that people do indeed enjoy a flat frequency response, but what most people
perceive to be a flat response is slightly rolled off. A rolled off response will be superior for extended listening and be better suited an environment more reverberant than a recording studio control room, such as your home. While it is true that good studio monitors strive for totally flat response, keep in mind that these monitors function as monopoles with a low level of room interaction in the midbass through treble. This means that reflections from the room that arrive at the listening position are few. This decreased additive effect means a flat response won't be as fatiguing as it would be with more room reflections. Secondly, many studios use monitors for their "sound", or coloration. This might mean a non-flat response, harmonic distortion, resonances, or a combination of all of the above. This results in you having
no idea what "as intended" really means.
You are right in your intuitions about frequency response not being the end-all for speaker measurements. Indeed, it is only a starting point. I find that Stereophile tends to put out a nice little suite of measurements with their loudspeaker reviews. For me, it is an easy way to glance over a speaker to get an idea of its quality. The marketing department can't fudge the measurements at the third party very easily.
As for your apartment, I highly recommend room treatments. The VAST majority of your system's sound is the result of the room-speaker interaction. Buy high quality speakers and treat your room accordingly (this varies with the type of speaker you buy) and you're about 95% of the way there. Buy a high quality amplifier/receiver with low noise, flat response, inaudible distortion, and sufficient power to drive your speakers to levels that you desire, and you're home free. Connect any good source you want, your system will be performing as well as it can.
