1972 MGB Roadster Audio

Okay, this is for my girlfriend but I don't want to look a lemon with an answer...

What type of voltage regulator would I need to stop the stereo head unit drawing too much power when I add a pair of rear speakers. When a lot of electrics are running at the same time the head unit gives up the ghost. There are no other audio bits added just a 40x4 head unit. Please help, she promised me the best 60 sixty seconds of my life if I come up with a solution!

Hi Revo, it seems that if the head unit is cutting out on you with other components (electrics) on, that you may have a poor ground or an inadequate source of power for your head unit. With this in mind, I'd measure voltage at the battery when the vehicle is off and running to determine if the problem is originating from the vehicle's battery and/or alternator (possibly a generator in that vehicle). If all measures okay, I'd suggest connecting the head unit directly to the battery with a relay activated by your accessory lead currently going to your radio. 

Connect terminal #85 to the existing accessory lead, connect #86 to ground, connect #87 and the memory lead of the head unit to the positive side of the battery (fuse it), and connect terminal #30 to the accessory lead of the head unit. Also, make sure you use at least 16 gauge wire or better for all power and ground connections.

Good luck with getting those 60 seconds and let us know how you make out.

the12volt