In this presentation we will discuss instability mechanisms in turbulent jets, their importance for sound radiation, and their real-time control. The first part of the talk focus on low-order models for flow instabilities that underpin jet sound radiation at low azimuthal wavenumbers. We explore models with different degrees of complexity, derived using different frameworks: acoustic analogies, linear stability theory and resolvent analysis. Experimental and numerical data are systematically used to feed and validate the models, which are used to study jet noise on a number of different configurations, such as: subsonic static jet, subsonic jet in fight condition, supersonic (shock-containing) jets, supersonic impinging jets and forced jets. In the second part of the talk, we focus on the control of sound-generating mechanisms in subsonic jets. Particular emphasis is given to an experimental study of real-time control of axisymmetric flow disturbances responsible for jet noise radiation at low polar angles. Linear convective mechanisms in the initial region of turbulent jets are explored in order to perform reactive control, wherein the actuation signal is updated in real time based on sensor measurements performed upstream, resulting in an inverse feedforward approach. The control law is based on empirical transfer functions of the jet response to stochastic forcing and actuation, which are measured experimentally. We first consider an artificially-forced jet case, wherein the flow disturbances can be amplified above background levels, which makes it easier to detect them by the sensors. We then consider the more challenging case of a natural jet, i.e., without artificial forcing. We demonstrate the successful implementation of real-time reactive control of these disturbances, achieving order-of-magnitude attenuations of associated velocity fluctuations in the forced jet. In the natural jet case, we could obtain substantial levels of attenuation of natural turbulent jets, of about 60% in power spectra for the most amplified frequencies. These results open new directions for the control of turbulent flows and their associated sound fields.