Sorry for asking basic question, what is pre-out?
What i came to know from other Punto users, the OE HU has sufficient power to handle more powerful speakers.
Its not about power buddy, its the ability to connect an amp.
RCA Preouts are used to connect external amps to your head unit. These are the same red and white cables that you use for your home system. Basic head units usually have one set of preouts (front left, front right). Some head units have two sets (front left, front right, rear left, rear right), but most decent head units have 3 sets (front left, front right, rear left, rear right, subwoofer left, subwoofer right). Subwoofer outputs are sometimes called "non-fading" outputs because they are not effected by the head unit's fade control (front to back balance). If you're not planning on adding an external amp, you don't need to worry about RCA pre-outs. If you want to add an external amp (or amps), its always recommend getting a unit with two to three pre-outs.
If you are adding only one 4 channel amp to power front & rear speakers or front speakers & sub, then 2 pre-out HU is more than enough. But if in future, you need to upgrade to one more amp for your sub, then you may require 3 pre-outs.
What is the use of 4/5 channel amp? To amplify the sound?
Amplifiers are meant to reduce distortion in your speakers at higher volume & give a clean & crisp sound.
General myth is that amps may damage speakers because of the additional power. Not true. Infact, if speakers are played at high volume without an amp, then chances of the speakers going kaput are higher.
And which is the good brands for speakers?
there are many brands as i have mentioned in my first post. depends on your budget & availability.
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