Looking for some help understanding the power output of my factory HU. Relatively new to car audio.
2015 4runner, non-JBL, OEM stats claim 140w continuous. I used a plug and play PAC harness to connect a LC7i powered LOC to a 1000w amp; 60 RMS x 4 channels. Rewired all the doors to the new amp with new speaker wires.
The only spot I didn’t re-wire is the tailgate. I want to change out the tailgate speakers, re-wiring the tailgate is something I’m trying to avoid. I know 4runner factory rear door speakers are wired in sequence to the tailgate. My thought is that I could patch the two rear R & L doors with jumpers to put the power all to the tailgate speakers. I’m guessing that would only give me 35 RMS per speaker though using the factory power output.
Two questions:
1) am I correct on assuming I can get 70 RMS from the factory HU if it’s rated to 140 and I’m only using the rear right and left speaker wire outputs, pushing the power to the rear with the jumpers.
2) if I took the front and rear speaker outputs for left and right from the factory HU and connected them to the rear speaker wire (placing jumpers in the rear doors to send the full signal to the tailgate) would the full 140 RMS end up in the tailgate? Would the LOC that’s currently installed take some of that power away? I’m sure I could just put another amp in but trying to save on space here.
I figured the power aspect makes sense but I don’t understand if the signal would get messed up.
I guess my question is if I took all the outputs from the hu blended into two speaker inputs put it into one big speaker, would I get the full output from the HU power wise and can the speaker handle that signal? Would it sound good?
My thought was to do this and install a component system rated for 70 RMS each with some custom fabrications on the back tailgate.
Sorry if any of that is confusing, like I said I’m still learning. Thanks!
2015 4runner, non-JBL, OEM stats claim 140w continuous. I used a plug and play PAC harness to connect a LC7i powered LOC to a 1000w amp; 60 RMS x 4 channels. Rewired all the doors to the new amp with new speaker wires.
The only spot I didn’t re-wire is the tailgate. I want to change out the tailgate speakers, re-wiring the tailgate is something I’m trying to avoid. I know 4runner factory rear door speakers are wired in sequence to the tailgate. My thought is that I could patch the two rear R & L doors with jumpers to put the power all to the tailgate speakers. I’m guessing that would only give me 35 RMS per speaker though using the factory power output.
Two questions:
1) am I correct on assuming I can get 70 RMS from the factory HU if it’s rated to 140 and I’m only using the rear right and left speaker wire outputs, pushing the power to the rear with the jumpers.
2) if I took the front and rear speaker outputs for left and right from the factory HU and connected them to the rear speaker wire (placing jumpers in the rear doors to send the full signal to the tailgate) would the full 140 RMS end up in the tailgate? Would the LOC that’s currently installed take some of that power away? I’m sure I could just put another amp in but trying to save on space here.
I figured the power aspect makes sense but I don’t understand if the signal would get messed up.
I guess my question is if I took all the outputs from the hu blended into two speaker inputs put it into one big speaker, would I get the full output from the HU power wise and can the speaker handle that signal? Would it sound good?
My thought was to do this and install a component system rated for 70 RMS each with some custom fabrications on the back tailgate.
Sorry if any of that is confusing, like I said I’m still learning. Thanks!
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Usually the factory head units will have right around 18 wpc rms.
I wouldn’t plan on summing or bridging the factory head unit in an effort to get more output. That will likely result in no output.
My Toyota has jumpers going from the rear speakers to an loc that’s part of my aftermarket amplifier. The factory head unit power seems to be adequate for the smaller front speakers, and the extra amplifier is for a subwoofer.
I wouldn’t plan on summing or bridging the factory head unit in an effort to get more output. That will likely result in no output.
My Toyota has jumpers going from the rear speakers to an loc that’s part of my aftermarket amplifier. The factory head unit power seems to be adequate for the smaller front speakers, and the extra amplifier is for a subwoofer.
