Comcast network's cable TV service is now called XFINITY TV. XFINITY cable comes with three different types of cable boxes; standard or basic digital cable, DVR and HD DVR. Set-top boxes are required to access the Comcast digital cable search menu, movies ON DEMAND and HD channels.
Digital Cable Box
The digital cable box is the new standard or basic set-top box for Comcast cable. It is not DVR capable, but does provide HD channels. Digital cable uses a coaxial cable and compresses TV signals into data and transfers it to your TV without any loss of quality of picture or sound. The digital cable box is also called a digital converter box. It contains a small computer that processes digital cable signals and sends information back to the signal processing center so you can change channels and watch movies and programs On DEMAND.
The DVR receiver is a Comcast digital set-top box that can record and play TV shows and movies. It can store up to 80 gigabytes or 45 hours of standard basic cable programming. With the DVR Receiver you can record one show and watch another channel, or you can record two shows while watching a previously recorded show. It has the standard Record and Play features which allows you to pause and rewind while watching live TV. You can even program it to record an entire series or season of your favorite shows so that you never miss an episode.
The HD DVR set-top box has a higher storage capacity of up to 500 gigabytes. This means that it can save 300 hours of standard definition television, or 60 hours of HD television. The HD DVR has the same features as the DVR, with more storage capacity. It also is enabled with Dolby Digital 5.1 Surround Sound to give you the best sound quality to match your crisp HD picture on your TV.
3D set-top box?
Currently there is no special set-top box for saving 3D channels as there is for standard or HD TV. If you have a TV that can support and display 3D channels, you can hook it up to any Comcast cable box that provides HD channels with a HDMI cable.