add_filter('tc_sidebar_widgets', 'my_sb_widgets', 20);
function my_sb_widgets( $sidebar_widgets ){
  $my_params = array(
    'after_title' => '</h2><div class="widget-content">',
    'after_widget' => '</div></aside>'
  );

  $sidebar_widgets['right'] = array_merge( $sidebar_widgets['right'], $my_params);
  $sidebar_widgets['left'] = array_merge( $sidebar_widgets['left'], $my_params);

  return $sidebar_widgets;
}