I thought that on DLT tapes that it doesn't do any compression on the actuall data, but compreses the way it writes it to the tape. With a DLT 4000 drive it is twice as fast to write a tape compressed than it is uncompressed. From what I understand it uses two heads to write the tape instead of one. Maybe that is only hardware compression and software is different? I think that you may be thinking of something else. Maybe that is how it is compressed on other tapes but I don't think so with DLT or perhaps AIT-2. I would recomend that it has hardware compression. Much faster. I have seen the specs on the AIT-2 tapes and am rather impressed. I would love to get one of these drives. If you get a DLT-8000 drive you can compress the drive to store 80 GB of data ( I think thats right. The 4000 compressed is 40 and the 7000 is 65 I think ). I can get 100 MB a minute from my drive. The 7000 and 8000 drives are even faster ( up to 600 MB a minute ). If the drive models are confusing it is because I use a ADIC drive and don't know it these are specific to ADIC or it they are standard dirve models. Sorry if this is confusing. sim David Dyer-Bennet wrote: > "Austad, Jay" <austad at marketwatch.com> writes: > > > AIT-2! They are rather expensive though. Otherwise, DLT. AIT is much > > better though. AIT-2 is 100GB compressed, and tapes cost around $100 each. > > Actually, $100 for 100GB compares quite unfavorably to DDS-3 media prices. > > I'd love a drive in this size myself, but it's not on my budget. > > (And I wish people would not quote compressed sizes; most of what I > have to back up is already compressed via jpeg or mp3 or zip, and my > previous experience is that compression in backup can't do a thing > with such files. So I need to know the *real* tape size. I know that > most such claims are based on a factor of two.) > -- > David Dyer-Bennet