1 Channels = 4 feet

2 Channels = 8 feet

3 Channels = 12 feet

4 Channels = 16 feet

5 Channels = 20 feet

6 Channels = 24 feet

7 Channels = 28 feet

8 Channels = 32 feet

9 Channels = 36 feet

10 Channels = 40 feet

11 Channels = 44 feet

12 Channels = 48 feet

13 Channels = 52 feet

14 Channels = 56 feet

15 Channels = 60 feet

16 Channels = 64 feet

17 Channels = 68 feet

18 Channels = 72 feet

19 Channels = 76 feet

20 Channels = 80 feet

21 Channels = 84 feet