Wanting to install Rockford Fosgate6.5 tms6 speakers on my 2012 Street Glide I presently have a boom amp and speakers. The model of the amp is 76000071. I noticed that the Rockford speakers are a 4 OHM, but I believe the boom speakers are 2 OHM. I want to keep the existing amp and just change out my speakers. Has anyone done this before? Does anyone know if there are any issues installing the Rockford speakers with the amp I have?

 

@ 4ohms you will cut the watts in your boom by 50%. That will equal an unhappy rider. Boom really paints you into a corner.

 

Thanks for the info.

 

I installed 4ohm speakers (Mmats) and I am very happy with the sound with the boom amp, most here will tell you I’m crazy but I’m just giving my opinion.

 

I know this is going to be quite a bit of information that no one really asked for but I did a little research and found the following information.

When you change from a 2 ohm to 4 ohm speaker it reduces the output of the amplifier by half. So the Boom! amp was 300 watts or 75 watts per channel is now 150 watts total and 38 watts per channel when 4 ohm speakers are used. The biggest concern is the speaker sensitivity as well as the speaker impedance.

Speaker Sensitivity
Harley 89dB 1W/1M Lets assume (I know, I know) That the HD Speakers have a Speaker Sensitivity of 89dB 1W/1M (I think I am being generous).
RF 6.5tms6 91dB 1W/1M
MMats PA601cx 95db 1W/1M

Using the calculator on https://geoffthegreygeek.com/underst...r-sensitivity/ the maximum output from the boom! amp is as follows.
Harley Speakers 2 ohm Max volume at 75 Watts = 107.8dB
RF6.5 tms6 Spkr 4 ohm Max Volume at 38 Watts = 106.8dB
MMatsPA601cx 4 ohm Max Volume at 38 Watts = 110.8dB

This is why the Mmats are able to replace the Harley speakers and not loose volume. In fact they act as if there was a much larger amp because they are so efficient. It would take a 600 watt amp (150 per channel) replacing the Boom! amp to make the Harley speakers produce the same sound level as the Mmats. At that power I doubt the Harley speakers would survive.

Forgive me for the excessive post but as I look out the window there is all this white crap on the ground and I just want to ride. The joys of living in the midwest!