choosing speakers for disk masteringAlmost all monitors share a range of common drawbacks in terms of playing sound, and that will inevitably influence the decisions made during online mixing and mastering service work. That’s why these drawbacks deserve special attention. Some of them will be definitely present in low-cost models (typical for affordable mastering studios), but an acoustic system with too much of these flaws certainly doesn’t belong to the professional sound mixing facility.
Try to notice if a dull, slow and boomy bass sound is present. Colored, incoherent bass without a distinct tone is an extremely irritating characteristic of bad monitors. Professional studios speakers should play bass with a clearly audible pitch, not with a low-frequency hum of a single note with the music in the background.
Upper bass can be evaluated by listening to male speech. It shouldn’t contain accentuated or unnatural side tones similar to sound “from the box”. If it does, that’s exactly how your mix is going to sound.
choosing speakers for sound masteringSeparate bass notes shouldn’t be louder than the rest of the sound. If a volume of a single note differs from the other ones, it may indicate a problem with this frequency. When such monitors are used for mixing and mastering, defects are inevitable.
Deep bass sound must be quick, clear and have a decent density level. Quality is more important than quantity when we are talking about the bass.
If you want to know how bass must not sound, listen to the bad car subwoofers. Car audio systems emit maximum sound power on a single frequency; they are not designed for articulate melodic bass. 

To check what proper ly mixed songs sound like please check our mixing mastering before and after demos.