for (uint i = 0; i < enemys.length; i++)
{
p.update_sound_3d(enemys[i].sound, enemys[i].x, enemys[i].y, enemys[i].z);
}//cl
That is assuming that you have Sam's modified 3d sound pool, otherwise you will be forced to stick with 2d

//I haven't written bgt in a while and thus cannot guarantee error-free code
enemy@ enemies[];
class enemy
{
int x, y, sound;
enemy(x, y)
{
x = x;
y = y;
sound = p.play_3d("enemy.ogg", me.x, me.y, me.z, x, y, z, true);
}//cf
}//cc
//A sample enemy loop.
//Keep in mind that our enemy has a sound slot that they're holding onto for us to use later.
void enemyloop()
{
for (uint i = 0; i < enemies.length; i ++)
{
p.update_sound_3d(enemies[i].sound, enemies[i].x, enemies[i].y, enemies[i].z);
}//cl
}//cf

enemy@ enemies[];
class enemy
{
int x, y, sound, movetime;
timer movetimer;
enemy(x, y, mvt)
{
x = x;
y = y;
movetime = mvt;
sound = p.play_3d("enemy.ogg", me.x, me.y, me.z, x, y, z, true);
}//cf
bool can_move()
{
if (movetimer.elapsed >= movetime) return true;
return false;
}//cf
}//cc
void enemyloop()
{
for (uint i = 0; i < enemies.length; i ++)
{
if (enemies[i].can_move() == true)
{
//moving logic goes here
p.update_sound_3d(enemies[i].sound, enemies[i].x, enemies[i].y, enemies[i].z);
}//ci
}//cl
}//cf