I was sceptical at first, having had previous so-called *Bass Boosted* headphones that were lacking in quality, but I'm so glad I bought these.The sound is nothing short of amazing, with bright trebles, and crisp clear vocals, the bass is really good, but you need to download an equaliser to get the most out of the phones, (You can download a bass boosted graphic equaliser, free from Google Play, on your phone or tablet).With the equalizer on 50% Bass I swear that I could hear my brain vibrating, I had to turn it down to 30%, and the results were nothing short of magic.The bass is strong but without muddying and strangling the vocals, and like I said before the trebles were bright too.Build quality was I would say, strong if not exactly premium. You also get a wire to plug in your headphones if you're low on battery, for the Bluetooth.Being as these are Bluetooth headphones I expected a reduced quality over wired phones, but I couldn't detect any difference between the two.Distance on Bluetooth was about 30ft, I know because I tested it and that was through several walls and a few doors away.The only downside to theses headphones is that they take about 3 hours to charge from empty battery, but if you can live with that it's not exactly a deal breaker.I would definitely recommend these headphones if extra bass is your thing.Well worth the price, I would have been happy to pay double the price I paid for them.I love them.Go buy them.