Japa Yajna is entirely held for the devotees  and for general people. The term Yajna means sacrifice. In the Vedic period, fire sacrifices were being made by the spiritual aspirant and household devotees for fulfillment of their worldly as well as spiritual attainment. In the long run, these sacrifices have been turned into an unselfish activity of any kind. Here the term Japa Yajna means 'Upasana or meditation for a long time i.e, repetition of the names of Gods/ Goddesses given by their spiritual  gurus. The continuous practice of this Japa Yajna withdraws the mind of devotees from worldly affairs and concentration intensifies in a particular object i.e, God. Through the practice of this Yajna, the mind of devotees becomes calm and peaceful and they feel the blessings of the god bestowed upon them. 

         This Japa Yajna convention is occasionally held in our Ashrama to boost  and charge  spiritual practices in the presence of senior monks with their guidance.

we may recall  lines from  the Gospel of Sri Ramakrishna 

From The Gospel of Sri Ramkrishna:  Ist CHAPTER ,  FROM THE  SECTION  : MASTER AND DISCIPLE
"But one must go into solitude to attain this divine love. To get butter from milk you must let it set into curd in a secluded spot: if it is too much disturbed, milk won't turn into curd. Next, you must put aside all other duties, sit in a quiet spot, and churn the curd. Only then do you get butter.
"Further, by meditating on God in solitude the mind acquires knowledge, dispassion, and devotion. But the very same mind goes downward if it dwells in the world. In the world there is only one thought: 'Lust and gold'. AND 

From : Chapter VII, DHYANA AND SAMADHI , THE COMPLETE WORKS OF SWAMI VIVEKANANDA ,( Mayavati Memorial Edition)  VOLUME I , PAGE : 178 

 " We have taken a cursory view of the different states in Raja Joga, except the finer ones, the training in concentration, which is the goal , to which Raja - Yoga will lead us. We see ,as human beings that all our knowledge which is called rational is referred to as consciousness. My consciousness of the table, and of your presence, makes me know that the table and you are here . At the same time, there is a very great part of my existence of which I am not conscious. All the different organs inside the body, the different parts of the brain- nobody is conscious of these.

When I eat food, I do it consciously; when I assimilate it, I do it unconsciously. When the food is manufactured into blood, it is done unconsciously.
 When out of the blood all the different parts of my body are strengthened, it is done unconsciously.
And yet it is I who am doing all this;  there cannot be twenty people in this one body. How do I know that I do it, and nobody else?
It may be urged that my business is only in eating and assimilating the food and that strengthening the body by the food is done for me by someone else. That cannot be, because it can be demonstrated that almost every action of which we are now unconscious can be brought up to the plane of consciousness. The heart is beating apparently without our control. None of us here can control the heart; it goes on its own way. But by practice, men can bring even the heart under control, until it will just beat at will,  slowly or quickly, or almost sleep. "