REAR BUSS

The rear bass port, if that is what you are referring to, is nothing transcendental. In practice, if due to the geometric problems of the room you find yourself having one of the two monitors in a corner, it is very likely that you will hear much more the low frequencies of the monitor in the corner, precisely because bass frequencies cluster in corners and it is evident that if the monitor is placed right there, the effect of this clustering will be much more evident... To limit this problem, either place bass traps in the corner or alternatively plug or decrease the airflow of the monitor's air vent port. In essence, you create an internal pressure against the speaker vibration that limits the production of low frequencies. It is not a very elegant solution and is often also useless since practically all modern monitors have attenuator switches that allow you to reduce the low-frequency signal to avoid this problem.

Hi! thanks!!

It seems to me you are talking about speakers while instead I am talking about use in a PT AUX

So you're talking about Buses!

I have never heard of a Rear Bus.

A Bus is simply a signal routing. It's as if from a pipe carrying water, you took a little bit to use for other purposes. However, I don't understand what the sense of "Rear" could be. A bus is a bus; if you are working in quadraphonic sound, then you can direct part of the signal on the bus to other speakers (for example, the "rear" ones), but that seems nonsensical to me—working in quadraphonic, you can send the main signal directly there. The bus is usually used to process part of the signal with plugins or to direct part of the signal to headphones connected to outputs different from the stereo Out.

Can I ask you where you read this?