Installing new (to me) Head unit and Amp

ric · **Posted:** Mon Feb 10, 2014 1:41 pm

The most common cause of distortion is under driving a monitor. When I was using Polk DB651's I had to amp them for correct sound or they would distort really bad when turned up. The Infinity's sound much better with no amp that I run now.

kd4pbs · **Joined:** Thu Sep 05, 2013 10:34 am **Posts:** 350

My guess is that a previous owner had an amplifier installed, and that's what the control is for. No telling what the RCA jacks were for, but if they were in an easily accessible place, I'd guess it was for an auxiliary input for a portable music playing device. If the amplifier's power output is significantly greater than the stereo's built-in amplifier, the sound will have the capability of being louder, or being just as loud with less distortion. Only you can weigh how much you need it though; if it's loud enough for you, then I wouldn't worry about it.

kd4pbs · **Joined:** Thu Sep 05, 2013 10:34 am **Posts:** 350

The most common cause of distortion is driving an amplifier past it's output capability. It's called "clipping", and it causes greater heating of speaker voice coils at lower power levels than the speaker is rated, which can lead to speaker failure. One can cause an amplifier to clip below or above it's rated output, depending upon the supply voltage, heat dissipation, and load impedance. Another cause of speaker failure would be over-excursion due to much greater power being delivered to the speaker than it's rating, and is exhibited by a sharp popping sound where mechanically the voice coil is hitting the magnet assembly.

LVChris · **Posted:** Tue Feb 11, 2014 1:50 pm

kd4pbs wrote:

My guess is that a previous owner had an amplifier installed, and that's what the control is for. No telling what the RCA jacks were for, but if they were in an easily accessible place, I'd guess it was for an auxiliary input for a portable music playing device. If the amplifier's power output is significantly greater than the stereo's built-in amplifier, the sound will have the capability of being louder, or being just as loud with less distortion. Only you can weigh how much you need it though; if it's loud enough for you, then I wouldn't worry about it.

Thanks, those RCA jacks look to be outputs for maybe a moveable subwoofer based on the locations, 2 sets on the dash and 1 set under the L seat as in these pics:

ric · **Posted:** Tue Feb 11, 2014 3:15 pm

Or a PA system for those epic cove parties

kd4pbs · **Joined:** Thu Sep 05, 2013 10:34 am **Posts:** 350

Those aren't RCA jacks. Those are bayonet lugs that one would use for a power connection or speaker connection. I gotta wonder what that was for. Strange indeed! Ric may be on to something.

LVChris · **Posted:** Fri Feb 14, 2014 12:13 pm

kd4pbs wrote:

Those aren't RCA jacks. Those are bayonet lugs that one would use for a power connection or speaker connection. I gotta wonder what that was for. Strange indeed! Ric may be on to something.

I think you mean banana jacks...like these

http://www.cablestogo.com/product/29785?utm_source=Google&utm_medium=Shopping&utm_campaign=SEM&gclid=CLyS4qWOzLwCFYdgfgodci8Auw

but they can be used for a subwoofer...or any external speaker I guess. Going to try to chase the wires next time I am on the boat. I spent hours in that stereo area and come to think of it...never saw any extra wires that would connect to these? Now I am really curious.

kd4pbs · **Joined:** Thu Sep 05, 2013 10:34 am **Posts:** 350

My fault; yep... Banana jacks, and you can screw a fork terminal down to it as well as a banana plug. It would be used for any "low voltage" application. Odd setup on a boat for sure.

ric · **Posted:** Mon Feb 17, 2014 3:41 pm

I've seen older wake/ski tower speakers with that connection.

www.iFourWinns.com

Installing new (to me) Head unit and Amp

Who is online