adding default values for custom field arrays

I am using a plugin for an events calendar. My client will mostly be starting and stop all events at the same time so i am trying to set default values for the start and stop times. How can i do this? I believe this is the section i would add it to.

$cr3ativconference_fields = array(
	array(
            'label' => __('Date', 'cr3at_conf'),
            'desc' => __('Choose the date.', 'cr3at_conf'),
            'id' => 'cr3ativconfmeetingdate',
            'type' => 'date',
            'std' => ''
        ),
	array(
        'label'    => __('Start Time', 'cr3at_conf'),
        'desc'    => __('Select the start time. 24-hour clock, 01:00-00:30', 'cr3at_conf'),
        'id'      => 'cr3ativ_confstarttime',
        'type' => 'text',
        'std' => ""
    ),
	array(
        'label'    => __('End Time', 'cr3at_conf'),
        'desc'    => __('Select the end time. 24-hour clock, 01:00-00:30', 'cr3at_conf'),
        'id'      => 'cr3ativ_confendtime',
        'type' => 'text',
        'std' => ""
    ),
	array(
            'label' => __('Location', 'cr3at_conf'),
            'desc' => __('Enter location.', 'cr3at_conf'),
            'id' => 'cr3ativ_conflocation',
            'type' => 'text',
	     'value' => 'hawaii',
            'std' => ""
        ),
	array(
            'label' => __('Speaker', 'cr3at_conf'),
            'desc' => __('Select the speakers.', 'cr3at_conf'),
            'id' => 'cr3ativ_confspeaker',
            'type' => 'post_chosen_speaker',
            'std' => ""
    ),
	array(
            'label' => __('Highlight Style', 'cr3at_conf'),
            'desc' => __('Select this checkbox if you would like to have a highlight this session.', 'cr3at_conf'),
            'id' => 'cr3ativ_highlight',
            'type' => 'checkbox',
            'std' => ""
    )
);