High Pass Passive Crossover - effect on amplifier

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Hi folks, this is kind of an odd question but figured I would fire it out there. I have a 2016 Silverado pickup and I have swapped out the factory speakers. Now I am having issues with the factory radio/amplifier that is powering these speakers over heating and clipping after extended periods of play.


Would putting a passive high pass crossover on the speakers ease the load on the amplifier at all? I am trying to fix this issue.
 
Hi, check the load !
It's easy that two pairs of 4 Ω speakers are wired in parallel in each channel, so total Z= 4/2=2 Ω
The amplifier would run hot and easily going into protection mode.
It's not a matter of frequencies but impedance.




I didn't even check when I bought them but the infinity reference speakers I replaced factory with are 3ohm. That's not good. My understanding was that using passive crossover networks you could reduce at least some of the load the amplifier sees by eliminating some of the frequency spectrum the load is spread across...maybe I am wrong.


I am just trying to put a band aid on this before I install separate amplifiers for my highs.
 
Blocking the bass (with a capacitor or LC high Pass) will reduce the overall load. The impedance will still be the same at mid band, but go up in the bass. Whether or not that off loads enough to make the amp happy will depend on what kind of music you're playing - basically how much bass you were feeding your speakers when running full range. And whether the protection circuits in the amp are instantaneous or use some kind of time averaging.
 
Blocking the bass (with a capacitor or LC high Pass) will reduce the overall load. The impedance will still be the same at mid band, but go up in the bass. Whether or not that off loads enough to make the amp happy will depend on what kind of music you're playing - basically how much bass you were feeding your speakers when running full range. And whether the protection circuits in the amp are instantaneous or use some kind of time averaging.

Thats exactly what I was thinking. I appreciate you verifying my idea. I will likely crossiver with a passive 80 hz high pass and see if that helps. I dont see how it couldnt help.
 
My guess is that the factory HU is probably a 4-ohm matched unit and pretty hard-headed about keeping things that way....

However.... to the 3-ohm factory Infinity's.

This may seem non-intuitive, but depending on what speakers you use - a number of 3-ohm speakers are 'viewed' by the amp (with crossovers) as 4-ohm impedance given how they're built - which is pretty happy with most amps. Infinity 3-ohm speakers are a pretty typical example of this.

This doesn't mean that this is good with all factory HU amps. In fact, aftermarket HUs with amplifiers (Pioneer comes to mind) can also have issues. The amplifiers are anemic at best....

Best solution IMO is get an amplifier that is 2-ohm stable for the number of channels you are using. the Infinity Reference series are pretty efficient (60W to 90W RMS depending on the model), so you wouldn't have to break the bank for such an amp.
 
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