I purchased a set of four DB651's to replace the factory speakers in my 2004 Nissan Sentra. My intention was to replace the entire factory sound system piece by piece, but once I installed these speakers I realized I didn't need to change out my head unit or add an amp. These speakers sound perfect with the factory HU. I can turn the HU up to maximum volume and the Polk can handle it with no distortion. When I first installed them, I had a raspy popping sound, but I realized the factory subwoofer was still connected. Since disconnecting the Sub the sound has been perfect! These speakers pick up the bass perfectly, so I decided not to add a sub at all. The sound isn't competition quality, but more than what I'll ever need. Perfect full-range speakers for the average listener. Purchasing these speakers saved me a lot of money on replacing the rest of my system. Thanks Polk!! You have a new fan!

Purchased these along with Polk's db6501 component speakers. Great spekears! Can take a lot of input from the amp with no distortion! Very pleased and would definitely recommend these!!!

I bought these to replace speakers in a Pontiac vibe. I am extremely please with my choice. I also replaced the factory radio because the CD was skipping and hooked these speakers up to a JVC replacement radio. Wow, what a difference. I read several reviews b4 I bought these and would agree with many people that these speakers sparkle with brilliant sound. The replacement was easier than I thought. It was an excellent choice and I would recommend it to anyone.

I installed this in a 24' pontoon boat. WOW!! These are the best sounding speakers for the price, very good base with mimimal distortion. I am going to add another set in the spring. I could only imagine how these would sound in a car. If you are looking for a marine grade speaker for a reaonable price these are a great choice.

Just installed these today in my 1990 4runner in the front doors and bought speaker spacers wich were not required. Hooked them up to a orion cobalt 600.4 amp wow these things bump!! Ive read some reviews saying they have no bass thats crazy! These little things got a lot of bass plus highs and mids! Maybe the past reviewers were not putting enogh power to them. I also have a new pair of boston acoustic 6/9 these things blow them out of the water in every way! So time to get rid of those and get another pair of these! Get these you will be happy!! Cant wait to hear how they sound in a month after a full break in period!!
Update Sep 29 09 Just had another pair installed in the back and all I have to say is WOW!! Like I said before I had Boston Acoustic 6/9 s95 in boxes and they just cannot hang with these! You can get away without a sub with these! Love em!