Mojo...I'm not sure if I have v4 or not...I looked on my invoice and on the back of my speakers and I can't find a tag that says what version they are. Also..when I listened to my uncles system, he had qs8s...but traded them in on the qs10s...I actually have my uncles qs8s that he traded. The last time I visited he had the qs10s installed..and they sound killer!