Modify the Site Header URL in Genesis

Change site title url in Genesis

/**
 * Logo URL
 *
 */
function dy_site_title_url( $title, $inside, $wrap ) {
	$inside = sprintf( '<a href="%s" title="%s">%s</a>', esc_url( 'http://www.example.com' ), esc_attr( get_bloginfo( 'name' ) ), get_bloginfo( 'name' ) );
	$title = sprintf( '<%s id="title">%s</%s>', $wrap, $inside, $wrap );
	return $title;
}
add_filter( 'genesis_seo_title', 'dy_site_title_url', 10, 3 );

or

//* Modify the header URL - HTML5 Version
add_filter( 'genesis_seo_title', 'child_header_title', 10, 3 );
function child_header_title( $title, $inside, $wrap ) {
    $inside = sprintf( '<a href="http://example.com/" title="%s">%s</a>', esc_attr( get_bloginfo( 'name' ) ), get_bloginfo( 'name' ) );
    return sprintf( '<%1$s class="site-title">%2$s</%1$s>', $wrap, $inside );
}