SUB_OUT_L, SUB_OUT_R, or just a single SUB_OUT
One or more SUB connections could appear on the rear of the Android headunit.
What is SUB?
SUB is a shortened name for sub-woofer. This is the speaker that produces very low-frequency sounds. The sub-bass is from the sub-woofer and is all about the bass.
8x9s or standard factory-fitted speakers can be as small as 5″ in diameter. These small speakers are good for mid-range sound production but don’t have the bulk for a deep bass, the sub-bass.
Bring in the SUB
The subwoofer is often an aftermarket fitment to expand the speakers’ sound range. The subwoofer is ideally run from its circuit and output on the Android headunit. This allows for the greatest fine-tuning at the headunit end, bass fader, or better, the EQ. This is why some better-thought-out Android headunits have a subwoofer output. Better yet, they have SUB_OUT_L and SUB_OUT_R for greater compatibility with the various aftermarket subwoofers available.
- SUB_OUT is the sub-bass output for a sub-bass speaker (MONO)
- SUB_OUT_L is the sub-bass output for a sub-bass speaker (LEFT Channel)
- SUB_OUT_R is the sub-bass output for a sub-bass speaker (RIGHT Channel)
Plugs and Sockets
The SUB_OUT (or often shortened to just SUB) on an android headunit will either be an RCA (Phono) socket on the rear panel, or it could equally be the same RCA (Phono) socket on a flying lead bundle. It all depends on the manufacturer. The sockets on the rear panel are cheaper to produce and give the lowest installation flexibility. The flying lead bundle means production costs are higher due to the extra parts, picking, and packaging. But the flying lead has the greatest flexibility for installation options.
RCA/Phono SUB connector
SUB connections from the Android headunit are usually an RCA (phono) socket, which requires a matching plug. The SUB RCA/Phono plug is shown in the picture below. The RCA phono socket is used on many Android headunit connections and is easily confused. If the SUB out isn’t working, and the EQ/Bass fader app is set up okay, check the SUB out on the Android headunit is connected to the SUB_IN of the sub.