Sc-815 Premium Sound - 850r Wagon

[Sharkey]

Ok, so I've done some searching, and haven't really found a definitive example of what I'm curious about.

As I understand it, the front dash tweets are run from an internal amp in the HU, then the front door speakers

are run from the front channel of the amp, while the rear door speakers and D pillar tweets are run parallel

off the rear channel of the amp at 8 ohms each to prevent excessive load.

Whew!

My question is, if that all is correct, can I run 4 ohm speakers in the front doors since that channel is not run parallel?

[Sharkey]

So with all the audio gurus here, no one has an answer on this one???? :huh:

[tcyc1984]

I'm not an audio guru, but after some researches and trial & error, I can give you my 2 cents

Its doable because the spec of the HU's built-in amp is 4x25w @ 4ohm and the indash amp behind the headunit is 4x40w or 4x50w @ 4ohm as described in user menu. Even you are running SC-900/901 headunit that requires the front channels of the indash amp to drive both the front door speakers and the dash tweeters, it will work (but it requires you to have the wiring that allows the amp to drive the tweeters) because the factory dynaudio speakers are 4ohm all around except for the rear desk woofers(for sedan). Theres one thing you have to pay attention is that when running lower ohm (i.e. a single 2ohm, or two 4ohm speakers in the same channel) speakers than the ohm rating of the amp (i.e. 4ohm), you will want to avoid tuning the volume all the right up because the speakers with lower ohm rating will withdraw a higher wattage (i.e. for the same amp, it will give 4x40w @ 4ohm & 4x60w @ 2ohm), you will overheat the amp and destroy it (or even your car lol.. ) If you keep the volume down, the speakers will draw less power so the amp will be safe. The factory speaker system has built-in crossver to prevet that, but for after-market ones, you have to wiring the 4ohm tweeters and 4ohm speakers through a 4ohm crossover, so the overall ohm will remains 4ohm, otherwise it will turn to 2ohm.

After all the background info just for the sake of insterest, the answer is basically yes. One bad thing about your setup is that when I was test fitting my dynies, I installed 4ohm tweeters while keeping 8ohm front speakers, I immediately noticed the imbalance of the sound stage, and the imaginery of the tweeters had increased to the level that it dominated the front channel and covered the mid and base. Since you are driving the tweeters and front door speakers through different amp, you can replace the tweeters with the 4ohm ones also, so the sound stage will be more balanced. Just remember when you are replacing the front tweeters, get the ones with built-in high pass filter so you won't constantly blowing your tweeters. Hope it help(and do everything at your risk)!