Audio Interference during start up

Patrick_L

Seaman
Joined
Jun 22, 2016
Messages
58
Loud pop in all speakers during engine start up. Power amp is wired to a bridged dual battery set up with 1,2 and 1+2 battery switch. It appears that im getting the current thru the ground and into the amp causing this during start ups :wacko:

Should i remove the negative bridge cable and find another spot to ground second battery to ?

Is that the likely culprit ?

Thx :)
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
16,313
Loud pop in all speakers during engine start up. Power amp is wired to a bridged dual battery set up with 1,2 and 1+2 battery switch. It appears that im getting the current thru the ground and into the amp causing this during start ups :wacko:

Should i remove the negative bridge cable and find another spot to ground second battery to ?

Is that the likely culprit ?

Thx :)
No.

Ultimately, every ground on the boat is tied together at the outdrive unless you have a separate ground plate.

You getting voltage spikes from the starter circuit. Put a ferrite on the power line to the amp and the source of it too is powered by the boat.

If that doesn’t work, you could have issues with your starter windings
 

GA_Boater

Honorary Moderator Emeritus
Joined
May 24, 2011
Messages
49,038
Has it always popped or this is new?

Which battery is powering the audio, Start or house battery? If it's the start battery, switch to the house battery.

If you turn the audio system off until the motor is stated you won't hear the pop.
 

Patrick_L

Seaman
Joined
Jun 22, 2016
Messages
58
I honestly don't know if this was the case or not because when i bought the boat i pretty much upgraded the system right away. As far as batteries, i think I've experimented with that already, cant remember 100% though so i’ll try again when i get to it.

And yep i do turn off the head unit before i crank.
 

Patrick_L

Seaman
Joined
Jun 22, 2016
Messages
58
I discovered a speaker wire “extension” concealed in the middle of the cable run along with similar frankenstein **** on the ground cable so I bought 1 gauge all copper for + and 4 gauge for the ground to replace them with and see how it goes 🤞🏼

i will also attach that ferrite on the +
 
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Patrick_L

Seaman
Joined
Jun 22, 2016
Messages
58
dingbat where would you place ferrite clamp ? Before the fuse box (between battery and fuse box) or beyond it (fuse box and stereo) ?
 
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