Polk Audio DB351 3.5-Inch Coaxial Speakers (Pair, Black)

I've always been a fan of Polk Audio so I thought I'd give these sub brand Alphasonic 6.5" inch speakers a try to replace my 2023 Kia Niro EV stock door speakers. The specs on these frequency speakers are phenomenal touting: 92 dB sensitivity, 28 Hz - 22,000 kHz, rivaling other ferrite magnet JBL, Infinity, DS18 and even Hertz. The watts aren't super great at 35w RMS each and 70w peak into 4 ohms. Advertising tries to make them sound bigger by adding the watts together, many speaker companies do this. Being this is what most stock audio systems produce I wasn't too worried about it, plus pair of these were so ridiculous cheap, I figured if they didn't sound good I'd just keep them or donate them and get better speakers. Couldn't be any worse than the stock speakers, it's amazing how cheap and low quality automakers go with their base stock audio, even in the year 2023 ! The new Niro stock speakers are junk. They do offer a premium package with Harmon Kardon + subwoofer but if you get a base model you get weak terrible speakers. There are six speakers in the Niro, two tweeters and two 6.5" inch woofers in the front doors, two 6" inch woofers in the back doors that can fit 6.5" inch with a bracket. The front doors need shallow mount or small magnets as the window glass encroaches into the speaker holes when rolled down. I originally bought Skar neodymium woofers for the front because you gain some volume with neodymium magnets and they tend to be more sensitive with a much smaller footprint than ferrite magnets to save on space. The Skars are also amazing for the price. FIRST INSTALL – I replaced the stock tweeters with Soundstream 1" inch, put the Skar neodymium woofers up front and also installed a powered subwoofer leaving the stock woofers in the back doors. Sound improvement over the stock audio was HUGE, also gained significant volume, more than enough for these old ears, just wish I had better DSP for tuning. Bypassing the 8" inch Kenwood sub definitely makes a massive difference, no matter what speakers you have in the doors a sub makes all the difference with low end, without one there's really no boom or thump. The sub I have isn't enough to rattle your windows, but it does add some low end vibrations. SECOND INSTALL - I later added a pair of Alphasonics to replace the rear door woofers. I will say the ferrite magnets are pretty small and was skeptical if they were true to the specs as most other quality woofers utilize much larger magnets and these are nearly the same small size as the stock woofers. Thought I'd install them in the back doors to make up for not having coaxials or 3-way. Difference was negligent as the rear speakers get less power from the stock amp and to hear them you have to change the balance so much you lose a lot of volume up front. So I switched the Alphasonics to the front despite already having nice tweeter separates installed and put the neodymiums in the rear hoping to gain a little volume with the higher output. Only made a slight difference and surprisingly the the 3-way Alphasonics did not sound too shrill or piercing in the high frequency bandwidth. So I've left the speakers this way for a few weeks now. The stock EQ is flat and I only have to use about 3/4 the volume on my sub versus 100% when it was running with wimpy muddy the stock door speakers. Overall I'm pretty satisfied as I'm not looking win any stereo competitions. The stock volume is plenty as I don't want to age my ears more than they already have. I may eventually replace the Alphasonics with Memphis Audio 6.5" neodymium at some point, but for now it's not really needed and the headroom and volume are a hundred times better than stock. Still not sure if the Alphasonics actually meet the specs, but they don't sound bad. Having dampening and doors with good airspace also makes a difference.

The picture displayed is incorrect but you do receive the actual Polk DB351 is you order it. I love the speakers, they are loud and can reproduce high notes really well. I suggest blocking any frequencies below 130 to have a nice clean and crisp sound. Overall I love them. I installed them on my 2008 NC NC1 Mazda Miata

Good

i installed these in 2014 kia optima, and the install was fairly easy, these fit almost perfect in the oem slot. they sound great, but would definitely recommend using am aftermarket head unit to power these or maybe even an amplifier, nothing to big of course. rms power is only 35 watts but that plenty for the range of frequencies these are for. The highs are crisp and well defined and will also handle a good portion of mid range freq's, of course these were not meant for lower frequencies but with proper installation and some sort of filter(be it a crossover or equalizer) you can these to sound good. i haven't installed the resistors that came with the speakers but i do plan and suggest you use these in order to keep them from playing to low a freq and risk blowing them. the tweeters have their own bass blocker installed so you don't have to worry about that. i suggest also using a soldering gun in order to get a good connection depending on your application. the speaker itself looks very nice as well so if its a build where you want to show off your speakers these would be a good choice. Polk audio makes really good products and i recommend this set of coaxial speakers for your install.

Fast delivery, received it much earlier than anticipated, no issues, everything was great. Would recommend these speakers.