Acoustic insulation material

A process for making an acoustic insulation web of fibrous material, the process comprising the steps of:

• providing a manufacturing system for making the acoustic insulation web, the manufacturing system including a first web former, a second web former, a single loom, and a heating mechanism;
• forming a first layer by way of the first web former and a second layer by way of the second web former, the first layer including a first plurality of low-melt binder fibers forming a first predetermined percentage of the first layer, the second layer including a second plurality of low-melt binder fibers forming a second predetermined percentage of the second layer;
• needling, by way of the loom, only the first layer such that the first layer is densified at least in part by the needling;
• and
• bonding thermally, by way of the heating mechanism, the first layer and the second layer together, the acoustic insulation web being a nonwoven batting, the first predetermined percentage being greater than the second predetermined percentage such that the first layer is denser than the second layer, the acoustic insulation web including the first layer and the second layer but having an absence of a third layer including a plurality of fibers, the loom preceding the heating mechanism in a machine direction of the manufacturing system and being positioned between the first web former and the second web former, the loom needling all the way through the first layer, the manufacturing system being configured such that the forming of the second layer occurs in-line with both the forming and the needling of the first layer prior to the thermal bonding of the first layer and the second layer together and thereby the manufacturing system having an absence of an unwinding device from which a needled first layer is unwound.