With Terratec, Power DVD 4.0 is provided. It offers a classic version of Dolby Digital decoding and Dolby Pro-Logic. However, there's no DTS technology, as is the case with Creative. Adding DTS sound requires the additional purchase of Power DVD software.

It is difficult to award grade points to one manufacturer over another as all of the devices offer sufficient power.

In any case, the sound is of very good quality whether it is at 5.1, 6.1, or 7.1 sound channel levels because very few DVDs offer anything more than 5.1. During a visit to the DVD section of a retail outlet, for example, we found only two DVDs that offered anything greater than 5.1.