Our ears, for the most part, hear the same sounds within Pianoforall Review a beat, but it's our brains that perceive differences in an audio dynamics sense. It all has to do with frequencies (Hz & kHz), and some people respond to the audio frequency range differently than others. You might prefer lows (bass), while "he" enjoys mids, and "she" likes highs (treble). As a rule of thumb, the human hearing range spans from about 20Hz-20kHz. Some people are more sensitive, or, not so sensitive to different frequencies. The subject of sound perception goes much deeper than the above mentioned, which is beyond the scope of this article. Just remember though that personal preferences & taste always outweigh any technicalities.
Now, let's talk about just a few of the technical aspects that can be incorporated when listening to and taking note of quality within a beat. (Remember: this is only a guideline, nothing is set in stone when it comes to music). The first thing you have to know is what you're listening for. With that being said, you'll be listening for an audio dynamic range. Basically speaking, all the instruments within a beat should mesh together, or gel very nicely. A good blend is key. You don't want too much or too little bass, same thing being said concerning the mids and highs. Here's a simple yet effective way to listen for a good dynamic audio range.
Play a beat and turn it down as low as you can, but still allow yourself to be able to hear most of the instrumentation. Your highs and mids should stand out more than the drums and bass. In some cases you don't hear any of the low end. Now, crank it up half-way. You should have some good solid drums hitting, your mids and highs should be there and everything will sound nicely blended. Depending on the type of bass used and how deep it is, you sometimes will not hear much of it when at the half way point.
Finally, what you want to do is crank it up loud! That bass line should definitely be there and sound solid, along with your drums and highs. This may sound weird, but this is the point where the mids should actually lower (or should I say perceive to sound lower). Try it out with your volume buttons and favorite beat, and even try it out with a commercial CD. You'll definitely hear that audio dynamic range in a commercial production.