Design Engineering050331 Boom Mat Speaker Baffles, 6.5" Round Slim (Pack of 2), Black

I've ordered two sets of these Boom Mats (6x9 and 4 inch). All arrived on time and well packed, but... After installing it on my car with amplified 6x9 JBL GTO 938 elliptic speakers, I didn't notice any sound quality improvement apart from new rattle sound. As someone said previously, they are good if you have amplified sub-woofer and cut your boom mat protected speakers HPF to at least 125Hz as otherwise mat volume (like litres and cubic inches) restriction won't allow them to move as freely as they should. If you allow your speakers to reproduce full frequency range with these mats, they will be torn apart very quickly. The thing I did notice same day is my JBLs started to overheat, when listened on moderate to high volumes. 4" boom mats didn't even fit my 10cm holes... All of the above makes 50 euro investment an absolute waist of money as I had to cut holes in these mats to fit them and they are not going to be replaced... It is not what I have expected, but it is all my fault - learn from it. :)

expensive crap

Great concept but fundamentally flawed; speakers move air in order to create sound and by removing all of the space in which a speaker can operate, you're greatly reducing the volume of air (and therefore the volume of your music) that the speaker can move. Ripped this stuff out of a Mazda MX5 MK3 and the difference is exponential. At max volume the tweeters were way louder than the 6.5 inch components in the door with the Boom mat behind them, with the mat removed the system sounds just as it should with plenty of depth and midrange kick.The speakers in the install are Focals 165's, so quite an expensive speaker.In short - don't buy this snake oil, if you're worried about your speakers getting exposed to the elements then protect them with some sort of membrane.