Use 4 drives for 2 Backup jobs in Backup Exec 2010

Hi,

I have 2 Backup jobs created in backup exec and before we just had 2 drives for LTO5 tapes,  recently we have added 2 new LTO6 drives.

I would like to know how can i do to optimize the backup time using all drives for our 2 lists, i mean can i assing 2 drives for a job? and the others for the second one?

Could anyone help me please?

Thanks a lot for your time.

Regards.