What is the difference between digital and magnetic ballasts?
There are a lot of little differences between conventional magnetic coil ballasts and the newer digital style. Without getting too technical, the differences lie in the way the ballasts mechanically operate. Magnetic ballasts work by sending a series of extremely strong electronic pulses through the fixture causing the light to cycle on and off 60 times per second. This creates a loud and somewhat annoying hum, not to mention occasional flickering lights. You may have experienced this in your own grow room, or even in office buildings, where this frustrating combination of noise and flickering lights is the leading cause of a condition known as Sick Building Syndrome.
Digital ballasts, on the other hand, precisely regulate the electronic pulse running through the electrical circuit enabling the entire fixture to sustain high initial lumen output. This means the entire light fixture operates at max capability throughout the duration of the light cycle. The digital pulse sends a much softer, steadier electronic pulse through the fixture at a rate of 20,000 times a second. Not only does the light bulb receive this in a much more relaxing way, so do the electric bill, the human body and possibly even the plant. This very steady, precise electronic current causes the ballast to run cooler, quieter, more efficiently, and even prolongs the life of the bulb.
Digital Ballasts cost more initially, but they pay for themselves within a few months. Digital ballasts are unquestionably the best ballasts on the market and are worth every last penny.