two dual-voice coil 4-Ohm woofers are connected in parallel and then wired to each other in parallel, a 1-Ohm monaural output would result (See Fig. 2). On the other hand, if your amplifier is rated for 4-Ohm operation in bridged or one-channel operation, series-connect the woofer voice coils (See Fig. 3). If the amplifier is rated for 8 Ohms, interconnect the voice coils of the woofer in series as shown to obtain 8-Ohm monaural output (See Fig. 4).
PARALLEL
2 Ω + -
2 Ω MONO
- +
Fig. 1
2 Ω + | - | + | - 2 Ω |
| 2 | | 1 Ω |
| | MONO |
- | | - |
+ | + |
Fig. 2
SERIES
8 Ω + | | - | | | | | - 8 Ω | |
| + | | | | |
| | | | | |
| | | | | | | | 4 Ω |
- | | | | | | | | MONO |
| | + | - | | | | + | | |
| | | | | | |
| | | | | |
Fig. 3
8 Ω + -
8 Ω MONO
- +
Fig. 4
SERIES/PARALLEL STEREO CONNECTION
Series wiring of each of two, dual voice-coil 4-Ohm woofers will result in a total impedance load of 8 Ohms at each channel of the amplifier (See Fig. 5). Otherwise, connect one woofer to each channel for 4-Ohm stereo operation (See Fig. 6), or two parallel-wired woofers (one-per-channel) for 2-Ohm stereo operation (See Fig.7).
+ | - | | | + | - |
8 Ω | | L | |
| | | | 4 Ω |
- | + | 8 Ω | | | STEREO |
| 4 Ω- | + |
+ | - | STEREO | |
8 Ω | | | | | Fig. 6 |
| | R | -2 Ω | |
- | + | + | | |
| | L | |
| Fig. 5 | | | |
| - | | | |
| | + | 2 Ω | |
| | + | - 2 Ω | STEREO |
R
- +
Fig. 7