The cognitive process: the stage of investigating consciousness
Many people try to read too much into the "17 thought moment sensing process". Please see page 164 of Bhikkhu Bodhi's "Comprehensive Manual of Abhidhamma" which gives Ledi Sayadaw's explanation.

Basically, in the case of eye-door, the "17 thought moment sensing process" captures a small patch of colour. This is followed by gazillions of mind-door processes that glue the entire field of vision together, grasp shapes, recognize shapes, grasp the name, recognize the name, etc. The comparing the object to past experiences comes much later after lots of thinking has been done. In other words, in the case of the eye-door, the "17 thought moment sensing process" brings a small patch of colour into the mind. That's it. All the subsequent analysis is done by gazillions of mind-door processes.

If you want the "bigger picture", the best place to start is the Madhupiṇḍika Sutta (MN 18), "Dependent on eye &amp; forms, eye-consciousness arises. The meeting of the three is contact. With contact as a requisite condition, there is feeling. What one feels, one perceives (labels in the mind). What one perceives, one thinks about. What one thinks about, one objectifies. Based on what a person objectifies, the perceptions &amp; categories of objectification assail him/her with regard to past, present, &amp; future forms cognizable via the eye."

In this sutta, the "compared / coupled to past experiences" that you are asking about happens at the final stage.