As a mobile DJ, selecting the right speaker system can make or break your event. While reading a spec sheet can give you a good idea of how good a speaker is, it's important to note that there's nothing better than listening to that speaker live at mid-high volume to get the most accurate representation.
Here are the things I look for when reading a spec sheet:
Max dB output: This gives me a vague idea of how loud that speaker is, so I know what size of events I can use it for. It's important to note that higher dB output doesn't always equal better sound quality.
Frequency response: This gives me an idea of the sound frequencies the speakers can reproduce. Human ears can hear a spectrum of 20hz-20khz, so getting a speaker that can reproduce most of that spectrum is a huge plus. While it's rare for a DJ speaker to reproduce sounds as low as 20hz, look for the closest thing possible.
Audio dispersion: This tells you how wide or narrow the speaker coverage is both horizontally and vertically. This matters depending on the space you are covering. If you are covering a narrow but longer room, you might want a narrower coverage. If you are covering a wider and shorter room, you might want a wider coverage. The average speaker has about a 90-degree horizontal by 30 degrees vertical coverage. While most column arrays are wonders, some other cabinets like the QSC K12.2 are narrower.
Size and weight: I always look at the size and weight of the speakers. Ideally, I try to get the most power I can out of the lightest and smallest footprint as possible. This will save my back and give more room for other things.
Price: I saved this for last because, with speakers just like with most things in life, you get what you pay for, and a good speaker won't come at a low cost. In my personal opinion, you want to budget at least $800 for a decent 12” speaker and about $1200 for a decent column array.
In conclusion, selecting the right speaker system is critical for a mobile DJ's success. Reading a spec sheet can give you an idea of how good a speaker is, but nothing beats listening to it live. Remember to consider the max dB output, frequency response, audio dispersion, size and weight, and price when selecting a speaker system.