Lasonic L-30
The L30 was a very popular box for Lasonic. It probably came out in the mid-80s. It has a red LED in each speaker that pulses to the beat. It takes 8 D-cell batteries. There were at least 3 different versions, shown in the photographs below. The most common is shown first. Then there's a silver version, which is very rare. The third photograph is a different generation of the L30K, with totally different styling.