I just found this free soundtrack:
Free Deep Meditation Sounds - Binaural Beats

Here is part of the description from the website:

This meditation aid may induce a deep trance state. It may take us to a deep place at a root energy level where we may experience a powerful connection with the core of our inner being. The OM sound is an ancient and powerful mantra which can create this connection (this can be verified by chanting it during an out-of-body experience).

The subtle binaural sound will harmonise our brainwaves to aid us in this. In some cases this may lead to what some people describe as “drowsiness”, sleep, with increased dream activity. Enhanced dream activity is a sign that we are awakening to our inner life. The sound may also induce a trance state which may lead to sleep paralysis, which can be used to induce OBEs or lucid dreams.

The two “Ping” sounds are there to create lucidity within this state rather than waking you up to physical awareness. You may use this by telling yourself beforehand that you wish to become lucid at this sound.