Apparatuses and systems are provided for changing the spectrum of light emission from a light-emitting diode (LED) light set. The LED light set may include LEDs, each of which having at least a first LED chip and a second LED chip configured to emit light at differing wavelengths. The first and second LED chips may be connected in series with opposite polarities. Responsive to receiving a power flow in a first direction from a power terminal, the first LED chip may emit light of a first color while the second LED chip may remain powered off. Responsive to receiving the power flow in a second direction opposite the first direction from the power source, the second LED chip may emit light of a second color different from the first color while the first LED chip may remain powered off.