An engine system comprising: an internal combustion engine having at least one combustion chamber and an exhaust manifold for conducting exhaust fumes away from the at least one combustion chamber; an exhaust system forming a flow path between an inlet in fluid flow connection with said exhaust manifold and an outlet; and an engine control unit for controlling operation of said engine system between at least a first operating state resulting in a first exhaust fume temperature range for a given rpm, and a second operating state resulting in a second exhaust fume temperature range for said given rpm, substantially higher than said first exhaust fume temperature range, wherein the flow path of said exhaust system comprises a low frequency sound attenuation portion including: a first tubing section having a first flow area (A 1); a second tubing section, directly downstream the first tubing section, having a second flow area (A 2) smaller than said first flow area (A 1); and a third tubing section, directly downstream the second tubing section having a third flow area (A 3) greater than said second flow area (A 2), characterized in that said first, second and third tubing sections are dimensioned in such a way that: a flow of said exhaust fumes through said third tubing section is laminar when the engine system is controlled by the engine control unit to be in said first operating state; and the flow of said exhaust fumes through said third tubing section is turbulent when the engine system is controlled by the engine control unit to be in said second operating state, wherein said first temperature range, in said first tubing section, is below 200oC and said second temperature range, in said first tubing section, is above 300oC. an internal combustion engine having at least one combustion chamber and an exhaust manifold for conducting exhaust fumes away from the at least one combustion chamber; an exhaust system forming a flow path between an inlet in fluid flow connection with said exhaust manifold and an outlet; and an engine control unit for controlling operation of said engine system between at least a first operating state resulting in a first exhaust fume temperature range for a given rpm, and a second operating state resulting in a second exhaust fume temperature range for said given rpm, substantially higher than said first exhaust fume temperature range, wherein the flow path of said exhaust system comprises a low frequency sound attenuation portion including: a first tubing section having a first flow area (A 1); a second tubing section, directly downstream the first tubing section, having a second flow area (A 2) smaller than said first flow area (A 1); and a third tubing section, directly downstream the second tubing section having a third flow area (A 3) greater than said second flow area (A 2), a first tubing section having a first flow area (A 1); a second tubing section, directly downstream the first tubing section, having a second flow area (A 2) smaller than said first flow area (A 1); and a third tubing section, directly downstream the second tubing section having a third flow area (A 3) greater than said second flow area (A 2), characterized in that said first, second and third tubing sections are dimensioned in such a way that: a flow of said exhaust fumes through said third tubing section is laminar when the engine system is controlled by the engine control unit to be in said first operating state; and the flow of said exhaust fumes through said third tubing section is turbulent when the engine system is controlled by the engine control unit to be in said second operating state, a flow of said exhaust fumes through said third tubing section is laminar when the engine system is controlled by the engine control unit to be in said first operating state; and the flow of said exhaust fumes through said third tubing section is turbulent when the engine system is controlled by the engine control unit to be in said second operating state, wherein said first temperature range, in said first tubing section, is below 200oC and said second temperature range, in said first tubing section, is above 300oC.