Yantra
An Yantra is a diametric representation of various Cosmic energies. Yantra is a sacred, geometric diagram, where just by looking, contemplating, your higher energies can be awakened.
Literally ‘tool’; usually a mystical and powerful graphic diagram, such as the Sri Chakra, inscribed on a copper plate, and sanctified in a ritual blessed by a Divine presence or an Enlightened Master
Sri Yantra
Understand, Mahadeva has thrown what is in his inner-space. That is Sri Yantra! That is Sri Yantra! If you consume whatever Mahadeva has revealed. Sadashiva is the rishi for the Sri Vidya. If you consume whatever is revealed by Mahadeva, you achieve the same space. Shivoham, Shivoham, Shivoham Satchitanandoham! Shivoham! Nithyanandoham! Shivoham! Understand Shivoham! Shivoham is the sound, verbalisation of Mahadeva’s inner-space. Sri Yantra is the geometrical representation, visualization of Mahadeva’s inner-space. With this Yantra and the sound, when Mahadeva opens up his inner-space to you guys, simply you will see that, first thing, your Kula Kundalini will be awakened to have the darshan of Mahadeva! - HH Paramahamsa Nithyananda Paramashivam
References
https://innerawakening.org/levelslevelsinner-awakening-level-1inner-awakening-level-1/inner-awakening-level-23/what-is-inner-awakening/ http://www.nithyananda.org/video/simple-lines-simple-sounds-have-power-0#gsc.tab=0