Hang on this one may get confusing. I want to measure twice and cut once so I would like a sanity check.

Last year I put in a new Sony HU and the adapter from Biketronics. Put Polk DB 651 both front and rear. All was well in Harley land.

I had intended all along to put in the Soundstream Nano 4 channel amp. Lately the wife is complaining about not hearing the music (she wears full face, I wear 1/2.) More on this in a bit.

So I get the amp, get it installed to the point where the power wires are done and it turns off with the ignition. I have connected the RCA outputs from the radio into the Nano. All is well.

Now the question is about the wiring with the Biketronics unit installed. I have seen the great write up UN did but that was with a stock HU.

It looks like there are two things to be done:
*The BT unit comes with a white plug that mates up with the white plug that comes from the radio. This provides some power wiring but also the wiring for the front speakers. It looks to me like I need to cut the 2/pr front speaker wires on the BT side, splice them and wire to the Nano. This bypasses the wires coming from the HU
*In addition the BT unit requires that the rear speakers be pin connected to an existing Harley connector (this is the way it has been and all is well). I would cut those wires where they come from the radio and connect them to the Nano as well.

Correct? at this point there would only be the RCA connectors going to the Nano, and all of the speaker wiring coming from the Nano. None of the speaker outputs from radio are needed at this point.


Now two other points:
*I currently have the RCA plugs from the radio connected to the Nano, but with all the standard speaker wires everything is working. At this point does it not matter that the plugs are in place and that speakers are still driven by the HU? No speakers are connected to the Nano
*As stated I have been trying to keep the volume up on the HU so my wife can hear in the back with the helmet on. Come to find out one of the Polk speakers is blown (don't suggest a 1/2 helmet - that horse left the barn.).

I do not want the replace the DB - I want to put in an MM like I should have done in the first place.. In looking at the MM they have 2.7 ohm rating while the DB have 4 ohm. Is it ok to mix these until I get the $$$$ to also purchase MM for the front.

Sorry for the long post!!!

 

I hope I followed you well enough to understand what your asking. I have a feeling you think you need to run RCA wires AND speaker wires to your nano.? If this is your understanding it is incorrect, basically all you need to do is disconnect your current speaker from your head unit and connect them to the speaker outputs on the amp. The only thing that should be supplying your amp is the RCA cables. You cannot run high level inputs( speaker wires) and low level inputs (RCA cables) at the same time. It will damage your amp. So in short RCA cable from the hu to the amp, speaker wires from the amp to the speakers. The hu speaker wires will not be used. And for your second concern, I asked un the same question last week and he informed me it is perfectly ok to run a 4ohm load on the front channel and a 2ohm load on the rear channel or vise versa. Hope this helps.

 

Thanks RideDaddy. We are saying the same thing - RCA into the AMP, speaker wires out - no speaker connections to the HU. Part of my confusion has to do with the Biketronics interface in the middle.

Anyone have a comment on the mix of 4 ohm front and 2.7 ohm rear?

 

From my experience (with a similar setup), you'll have NO issues running the MM651s in the back- that amp is 2ohm stable. You may have to adjust your front gains a bit higher due to the fronts getting less power than the rear (100W/ch @ 4ohms vs. roughly 130W/ch @ 2ohms), but you should be okay. I ran the same speakers in my bike for a bit until I got my CVO pods painted (at which point I ordered up all Biketronics speakers for the front): db651s in the batwing and MM651s in the Tour Pak pods and things worked fine. My setup now is two pair of 4ohm speakers in parallel both front and rear, so my amp is seeing a 2 ohm load on both front and rear channels.

Remember- the Biketronics module is there to replace the factory head unit's circuitry that allows for power, the handlebar controls and the speaker connections to the HD harness. Since you're running the SS amp, the speaker wiring between the BT1005 (just assuming that's your module) and the Sony is irrelevant; the BT1005's function becomes retaining handlebar controls and the power connections.

Your speaker connections should be from the output of the amp, not the head unit, so the BT1005 speaker wire connections aren't really doing anything currently. If I'm correct, to use your factory speaker wiring you'd need to connect the SS amp's outputs to the BT1005 speaker wires directly. You'd need to either unpin or cut the front speakers from the Sony-specific plug while the rear speaker channels on that Sony-to-BT interface are already unterminated. That will tie the SS amp to the BT unit, which then plugs into the HD 23pin connector which SHOULD then give you all-factory speaker wiring for all four speakers (IF you had rear wiring to begin with). If your bike did NOT have rear speakers, then you WILL have to run speaker wire back to the Tour Pak anyway, so it would be easy enough to just run new leads for all the speakers right off the SS amp while you're doing the rears.