A hydraulic system comprising: a hydraulic cylinder including a first chamber (116, 118) and a second chamber (118, 116); a first counter-balance valve (300, 400) fluidly connected to the first chamber (116, 118) at a first node (51, 52); a second counter-balance valve (400, 300) fluidly connected to the second chamber (118, 116) at a second node (52, 51); a first control valve (700, 800) fluidly connected to the first counter-balance valve (300, 400) and to a pilot (406, 306) of the second counter-balance valve (400, 300) at a third node (53, 54); and a second control valve (800, 700) fluidly connected to the second counter-balance valve (400, 300) and to a pilot (306, 406) of the first counter-balance valve (300, 400) at a fourth node (54, 53); characterised in that when a net load is supported by the first chamber (116, 118) of the hydraulic cylinder and when vibration control is active: a holding pressure is transmitted from the first control valve (700, 800) to the third node (53, 54) to hold the first counter-balance valve (300, 400) at a closed position and to hold the second counter-balance valve (400, 300) at an open position, the holding pressure being less than a load pressure at the first node (51, 52); and a fluctuating pressure is transmitted from the second control valve (800, 700) to the fourth node (54, 53) and through the open second counter-balance valve (400, 300) to the second node (52, 51), the fluctuating pressure causing the hydraulic cylinder to produce a vibratory response. a hydraulic cylinder including a first chamber (116, 118) and a second chamber (118, 116); a first counter-balance valve (300, 400) fluidly connected to the first chamber (116, 118) at a first node (51, 52); a second counter-balance valve (400, 300) fluidly connected to the second chamber (118, 116) at a second node (52, 51); a first control valve (700, 800) fluidly connected to the first counter-balance valve (300, 400) and to a pilot (406, 306) of the second counter-balance valve (400, 300) at a third node (53, 54); and a second control valve (800, 700) fluidly connected to the second counter-balance valve (400, 300) and to a pilot (306, 406) of the first counter-balance valve (300, 400) at a fourth node (54, 53); characterised in that when a net load is supported by the first chamber (116, 118) of the hydraulic cylinder and when vibration control is active: a holding pressure is transmitted from the first control valve (700, 800) to the third node (53, 54) to hold the first counter-balance valve (300, 400) at a closed position and to hold the second counter-balance valve (400, 300) at an open position, the holding pressure being less than a load pressure at the first node (51, 52); and a fluctuating pressure is transmitted from the second control valve (800, 700) to the fourth node (54, 53) and through the open second counter-balance valve (400, 300) to the second node (52, 51), the fluctuating pressure causing the hydraulic cylinder to produce a vibratory response. a holding pressure is transmitted from the first control valve (700, 800) to the third node (53, 54) to hold the first counter-balance valve (300, 400) at a closed position and to hold the second counter-balance valve (400, 300) at an open position, the holding pressure being less than a load pressure at the first node (51, 52); and a fluctuating pressure is transmitted from the second control valve (800, 700) to the fourth node (54, 53) and through the open second counter-balance valve (400, 300) to the second node (52, 51), the fluctuating pressure causing the hydraulic cylinder to produce a vibratory response.