I was concerned about running two wizzys as I read somewhere that the wizzy is rated at something like 3.87ohms and thus would drive an amp below two ohms. I emailed Carvin about this issue and their BXR series amps. Here is the reply: "Speaker impedance is based on the average impedance of the useable frequency range of the speaker (or cabinet of speakers). 3.87 ohms is very normal or actually being high for a 4 ohm speaker. Also if you use an ohmmeter on a speaker you will find most speakers read .5 to 1.5 ohms less than the average impedance. The B500 will not have an issue with two of these cabinets. Kris @ Carvin" This makes me feel alot better. I was told that running two wizzys at high volumes will shutdown an Iamp 800 (it happened to this player). I thought it was because of the low ohmage and was a little concerned about finding an amp that could push below two ohms... But not anymore!