So I've noticed that the rear channel output and the front channel output from the 6.5 head unit is totally different. The front channel is full sounding and the rears sound like muddled crap.
What I've done is utilize the 2 channel input setting (using the front output only of the radio to bt LL then to 2 channel input of amp) now all 4 speakers sound the same.
My question is this, is there an efficiency difference of 2 channel in-4 channel out vs 4 channel in-4 channel out?

I have 2 BT LL's in which I will adjust both to match and use 4 channel in-out but was just curious.

 

No, there will be no difference. You just eliminate the ability to adjust front and rear with head unit. No big deal. If you want more adjustment then add the second line leveler.

 

^ yup. That!

 

I question this thinking. Only because I have heard songs that play differently front to back.

 

Are you talking F/R imaging?

Why would u want that on motorcycle going 75mph? This ain't your living room 6.1 Dolby surround sound bro!!

 

Lol...alright...i get that!
Just saying that to hear the whole song. If that's the case,then why don't we just run all the rca's of the front channel?

 

Front to rear fade, you have a 998 so separate front or rear cross overs, running active crossovers and separate channel gains off your HU. There's quite a few reasons you'd want to but necissarily a deal breaker in this case for the OP.

 

Songs can play different left to right. That is stereo. Acdc was good at doing it. Front to back is impossible. You have 2 channels left and rightNo matter front , rear, mid, sub. Otherwise on a 2 speaker only setup, your headphones, your computer, etc you wouldn't hear those songs LOL.

 

I will add I do know some special recordings that are recorded on 6 separate tracks that if you have the proper surround receiver that will extrapulate the 6 tracks to a center ,f,r,sub but will also play fine through 2 speakers. You just wont get the full effect of the recording without the proper equipment, which we do not have in most mobile audio installs. I remember my old Eclipse Cd7000 had some dolby stuff in it that changed a lot around. All processing from the eclipse, not the recording.

 

That's what I basically figured. I will hook up and adjust both channels. I Like the ability to fade it anyway