5 Channel amp and going to two subs, questions on paralled vs series

MarkinPasadena

Just trying to make sure my numbers add up and what's the best solution to make everything happy and sounding good. This is on a 740 watt PPI amp.

So here are the amp numbers.

Power Specifications - Full Range Channels

RMS Power @ 4 ohms 60 watts x 4 channels
RMS Power @ 2 ohms 90 watts x 4 channels
RMS Power @ 1 ohm Not Stable
Bridged RMS Power 180 watts x 2 channels
Peak Power Output N/A

Power Specifications - Subwoofer Channel
RMS Power @ 4 ohms 250 watts x 1 channel
RMS Power @ 2 ohms 380 watts x 1 channel
RMS Power @ 1 ohm N/A
Peak Power Output N/A
Amplifier Specifications
Amplifier Class AB
Number of Channels 5

Well the MM's are 2.7 ohms so I know that's about 75 watts per speaker which equals 300 watts.

Now, if I put the two MM1040 4 ohm subs into parallel that will make them 2 ohms, consuming another 380 watts.

So now I'm at 680 watts on a 740 watt amp. I looking for sound quality and is this the most efficient way to do it? Or would it be better to do a both series and parallel together to keep them at 4 ohms? And I do apologize, I'm going off of memory dealing with car audio, and the last time I messed with this stuff was over 20 years ago.

Vital

You can't count total watts, it just doesn't wok like that.
5th channel will put out simply what's listed - either 250 @ 4Ohms or 380 at 2Ohms, nothing more. Even if you have no speakers at all on channel 1-4 that 5th channel will not just get that wattage "transferred" to it, it will still only put out what's listed in specs for that 5th channel.