Quote Originally Posted by Dirtstiff's F6B View Post
All will fit except the UM 651
All require trimming.
The MM are the premium speaker.
They come both as individual components or with the tweeter mounted with the woofer. Both have separate crossovers to mount.
The DB are good. DXI great, MM exceptional
MM are hardest to install.


J
According to Polk, all are Marine rated. The UM are made specifically for boats and wet enviornments. They have the grill and basket as one piece.
I'm replacing my DXI 651 Polks with a pair of MM 651, today.

I have a Polk PA D2000.2 amp. It's certified at 100 watts per channel RMS and 200 bridged. Very good amp.
The MM 651 also are rated for 100 watts per channel. RMS. They are a perfectly matched combo. The amp still has power for additional speakers or a sub woofer.

The MM 6501 which I don't have, are component speakers and have appx 50 watt higher RMS and Peak power rating along with adjustable crossovers.
I didn't want to find places to mount the tweeter, therefore I chose the MM 651.

Good luck in your choice.
Back to my project or as the wife says, obsession....
J