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ChrisC
10-27-2005, 07:39 PM
What do preamps do in a headunit?

If a HU only has 2 preamps outputs for the front and rear, can i still add a sub?

so if i have a HU that has 3 preamp outputs, does that mean the HU will power the front,rear,and sub. Meaning i wont have to buy an amp for the sub?

negativezeroz
10-27-2005, 07:41 PM
Preamp sends the signal...Im not a technical person. Frost will answer this. :)

You will need an amp for your sub. You can use a LOC if you only have front and rear preamps.....

JimJ
10-27-2005, 07:42 PM
Provides the signal needed to drive external amplifiers.

Some decks (like my Alpine 7894) combined the rear and sub pre-outs.

The pre-outs themselves can't power speakers; they simply provide a signal for the external amps that actually drive the speakers.

iceteebone
10-27-2005, 07:44 PM
they are rca outputs on the deck. they send music signals to the amps. the decks with 3 rca's, have a dedicated sub output that lets you specificly adjust the sub. you can run a sub on front and rear outputs, you just don't have a sub control on your deck and if you hook your subs to say the rear, when you fade to the rear you fade to the subs and vice versa.

newdavid
10-29-2005, 07:26 PM
i have one question abt preamps voltage my p8mp has 6.5 volts preouts and 770 has 4.0 volts preout

whats the difference i know the higer the volt the better but can someone explain it to me how that works...

thnaks