Why Don&#39;t DVD Recorders With Hard Drive Functionality Have Twin Digital Tuners? Part 1

!±8± Why Don't DVD Recorders With Hard Drive Functionality Have Twin Digital Tuners? Part 1

Consumers often ask why it is that DVD recorders with hard drive functionality tend not to have twin digital tuners, a feature that would allow them to watch one digital channel and record a different one. The reason for the omission of this useful option is explained in this two-part series.

The explanation for the lack of twin digital tuners in DVD recorders with hard drive capability is more complex than you might imagine. To begin with, you need to accept that in these machines, anything recorded to the hard disk has to be good enough for recording onto a DVD disk in a fraction of the time it takes to watch the programme.

So why is this?

This is because consumers are used to CD recorders and DVD recorders that can record much faster than the playback time, and a DVD recorder that could not do this would be labelled as "slow" and would probably not be commercially viable because of this.

So what has the DVD recording speed to do with dual tuner functionality?

Well, this is where things get complicated. I've explained that consumers need DVDs to be recorded faster than "live" playback time. To achieve this, any recordings on the hard disks of DVD recorders with hard drives; i.e. any recording that a consumer may choose to record to DVD disk at any moment; has to be already in DVD quality and format. The problem is that some of the Freeview channels don't broadcast in good enough quality for DVD disks.

This means that these Freeview signals need to be converted to DVD quality as they are written to the hard disk of the machine, just in case a you choose to record the programme to a DVD disk later. The conversion process takes as long as watching the programme. Because it is done in the background as the programme is broadcast, you don't notice any delay. After the programme has ended, you have it in DVD quality on the HDD hard disk, which means it is ready for recording to DVD later at the expected faster-than-live speed.

So now we have explained the reason that any recording to the hard disk has to be converted into DVD quality. In part two of this series we will discover why this conversion process is the reason that almost all DVD recorders with hard drive functionality don't have twin digital tuners.