Soundown

About Soundown: Decades of Noise Control Engineering

Not all sound is welcome. The drone of a diesel engine, the relentless vibration traveling through a hull or firewall, the low-frequency hum that follows you from the engine bay into the cabin — these are the noise problems that Soundown has been solving since 1983. Founded in Salem, Massachusetts by noise control expert Joseph Smullin, Soundown has grown into a world-recognized name in acoustic engineering, with expertise spanning marine, industrial, architectural, and medical applications.

What sets Soundown apart is the depth of science behind every product. Rather than offering a one-size-fits-all solution, Soundown engineers noise control from first principles — studying how sound waves propagate through different materials, how vibration transfers through structure, and how to interrupt those pathways at the source. The result is a product line that doesn't just muffle noise, but targets it systematically.

Sound Insulation That Works

Soundown's flagship offering is its line of sound insulation composites. These materials are engineered to absorb airborne noise within machinery spaces while simultaneously blocking sound transmission through walls, panels, and bulkheads. A hallmark of their approach is the use of mass-loaded vinyl sandwiched between layers of fire-retardant polyether foam — a construction that centers the acoustic barrier where it does the most work. These composites are designed specifically to attenuate the bass and mid-range frequencies generated by engines, generators, and pumps, where conventional insulation often falls short.

From acoustic foam and damping tiles to mass layers and vinyl composites, Soundown's insulation catalog addresses virtually every noise pathway. Their materials have been specified in some of the most demanding environments in marine history, including large custom yachts where passenger comfort and quiet operation are non-negotiable.

Engine Compartment & Hood Insulation

Engine noise doesn't stop at the engine room door. Soundown's hood insulation pad solutions bring the same acoustic engineering principles to engine enclosures and compartment liners. By lining the inner surfaces of engine covers and bays with purpose-built composite materials, these products dramatically reduce the radiated noise that would otherwise transmit directly into the cabin or cockpit. Fire retardancy is built in, ensuring that thermal and acoustic performance don't come at the cost of safety.

A Trusted Name Across Industries

Soundown's reputation has been earned not just through product performance, but through technical credibility. Independent testing has consistently placed their composite barriers among the most effective noise control materials available. Their product line continues to evolve — incorporating advanced materials like microporous insulation and micro-cellular elastomers — ensuring that engineers and boat builders alike have access to the most current noise control technology. Whether you're outfitting a new build or quieting an older vessel or vehicle, Soundown offers proven solutions backed by over four decades of acoustic expertise.