is it possible to use the factory non navi (TSX) to hook up a aftermarket sub?
or
is it possible to somehow take the 6x9 woofer and connect, maybe bridge left and right, to an aftermarket sub?

 

The only way you could do it would be to use a dual-voice-coil 4-ohm speaker in place of the two R 6x9 speakers (which are running off of two separate channels, but are summed to mono by the amp's internal xover. You can't bridge it, it's already bridged on every channel.

It would be a total waste of time, because the OEM amp is like 18W x 8 if rated using the CEA-2004 rating. It uses two 4-channel high-power deck amp chips inside (which are internally bridged). These ICs do lousy at low-frequency power response.

Better off either upgrading the 6x9s or getting a sub and an amp.

 

yeah, im looking to upgrade bass. was looking the easiest way. thanks for help though.