The Prius has the same six speaker system as the Camry hybrid but it is def louder inside than the Camry. Some of that is def due to a noticable amount less insulation in the roof area. I noticed this browsing the forums here so I added not only butylene panels but also 237mil foam to the entire roof, most the front doors, and key parts of the hatch area. I also used a can of expansion foam in the gaps of the rear quarter panels. I haven't added the sub and dsp yet but when is wired for it under the driver seat. The Hertz dieci sound really nice and clean. Has to turn the mid down a couple ticks but surprisingly bass response from them. haven't spent much time driving the last 10 days or so just tearing it apart and modifying it so I'll update after more seat time .