One thing every person (including myself) will say at some point when discussing audio products is “it sounds good to me” or “it sounds great” or something to that effect. The problem is, unless you put in some effort, it is very easy to fool a person to decide for themselves something sounds good. This extends not just to the layperson, but to people who have listened to dozens of speakers and reviewed them. It extends to myself and it extends to you.
The first thing that will fool you is volume. Human physiology can’t tell the difference between small changes in volume when they are separated in time. However,a bit more volume usually means that more details in the recording are noticeable, and a human will prefer slightly louder music consistently. This effect is so strong and and so universal that the music industry capitalizes on it. They do processing to make music sound louder, even with the volume knob in the same place. Search “Loudness wars” to find out more about what’s going on in industry. When you’re making off the cuff assessments of sound quality, you are likely choosing something based on the perceived loudness of what was played, rather than accurate reproduction.
However, if you learn to stop yourself from looking for stuff that “sounds good” and start assessing individual traits of the sound and details, you can get past this effect, to a degree. The basic idea, for me, is to find songs which you know very well and can listen to a hifi setup. Chances are if you go to a Magnolia at Best Buy they’ll let you do that. You have to listen very closely, to every little piece and spin it around in your head. That will give you a reference to compare to.
Even if you get this far, there are still traps people fall into. The first is most lay people equate presence of bass with overall quality. This, (along with branding) is what Beats audio is selling you: overpriced headphones with a bass boost. Of course, once you’ve learned to recognize this common selling point, there’s another trap you fall into: you start thinking lack of bass or a boost in treble is a sign of quality. Speaker companies take advantage of this. And that’s why measurements are so important; you want to see these kinds of issues plainly. Even then, you need to look at multiple measurements to get an understanding of the reproduction qualities of the speaker. With keen listening and measurements, your can get a very good basis with which to judge a speaker. Anything less and you or a reviewer are making a hasty decision.