I have a set of these speakers that I run along with a set of VDO 6" splits. I've tried numerous big name brands of speakers (Sony, Pioneer, Kenwoord, JVC), and these VDOs out-do all of them! The speakers provide it all, very clear treble and mid range sound, bit more importantly they have fantastic base. I found that with a full set of VDO speakers (6x9's in the rear plus the 6" splits in the front) running through a 4 channel amp I did not even need a sub.
Just be sure to get the HSP range (as opposed to the SSP's). The HSPs have the titanium finished cone and the full butyl rubber surround (this is an important part of these speakers performance). I actually came across this opportunity to write a review as I was scouring the net trying to find a set for my girlfriend, who now wants to kit out her Hyundai Tiburon with VDO speakers.
Only word of caution is that these badboys have a massive magnet on the back of them, so size-wise they are quite deep. Be sure to check the installation depth available as they require more depth space then your average speaker.
The VDO brand is not as well regarded as others, but I can not speak highly enough of these speakers. Give a set a go and you will not be disappointed!
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