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Ducting Silencers

30 products

Duct silencers — also called acoustic attenuators — are installed within ventilation ductwork to reduce airborne noise transmission through the system. Our range covers circular duct silencers and rectangular duct silencers for HVAC, commercial ventilation, and building services applications where noise control is a specification requirement.

Commonly installed downstream of fans, AHUs, or at room terminals to reduce breakout noise and meet acoustic performance targets in offices, hotels, schools, and residential developments.

What is a duct silencer / attenuator?

A duct silencer (or acoustic attenuator) is a lined duct section containing sound-absorbing material — typically mineral wool splitters. Air passes through the gaps between the splitters while noise energy is absorbed, reducing the sound level transmitted through the ductwork.

Circular or rectangular — which do I need?

This depends on your ductwork system. Circular silencers suit spiral or round ductwork systems; rectangular attenuators are used in flat-oval or rectangular duct runs. Both are available in a range of sizes to match standard duct dimensions.

Where should a duct silencer be installed?

Typically immediately downstream of the fan or AHU, or at branch points where noise could propagate to occupied rooms. Your acoustic consultant or ventilation designer will specify the insertion loss (dB reduction) required at each octave band frequency.

Do you offer silencers for both supply and extract systems?

Yes — our silencers are suitable for both supply and extract ventilation systems. Ensure the unit is rated for the airflow velocity and static pressure of your system.

Showing 1 - 24 of 30 products

Systemair LDC circular silencer with 100mm diameter and 300mm length, designed for ventilation duct noise reduction.

Systemair LDC circular silencer with 100mm diameter and 300mm length, designed for ventilation duct noise reduction.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 100mm Dia x 300mm Long

100mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£71.99

Systemair LDC Circular Silencer 125mm Dia x 300mm Long - eFans Direct Ltd

Systemair LDC Circular Silencer 125mm Dia x 300mm Long - eFans Direct Ltd

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 125mm Dia x 300mm Long

125mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£79.99

Systemair LDC Circular Silencer 125mm Dia x 600mm Long

Systemair LDC Circular Silencer 125mm Dia x 600mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 125mm Dia x 600mm Long

125mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£81.99

Systemair LDC Circular Silencer 100mm Dia x 600mm Long

Systemair LDC Circular Silencer 100mm Dia x 600mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 100mm Dia x 600mm Long

100mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£82.99

Systemair LDC Circular Silencer 150mm Dia x 300mm Long

Systemair LDC Circular Silencer 150mm Dia x 300mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 150mm Dia x 300mm Long

150mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£94.99

Systemair LDC Circular Silencer 200mm Dia x 300mm Long - eFans Direct Ltd

Systemair LDC Circular Silencer 200mm Dia x 300mm Long - eFans Direct Ltd

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 200mm Dia x 300mm Long

200mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£99.99

Systemair LDC Circular Silencer 100mm Dia x 900mm Long

Systemair LDC Circular Silencer 100mm Dia x 900mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 100mm Dia x 900mm Long

100mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£109.99

Systemair LDC circular silencer with 150mm diameter and 600mm length, shown in a close-up of the industrial ventilation component.

Systemair LDC circular silencer with 150mm diameter and 600mm length, shown in a close-up of the industrial ventilation component.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 150mm Dia x 600mm Long

150mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£110.99

Systemair LDC Circular Silencer, 125mm diameter and 900mm long, showing the cylindrical design and connection ends.

Systemair LDC Circular Silencer, 125mm diameter and 900mm long, showing the cylindrical design and connection ends.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 125mm Dia x 900mm Long

125mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£113.99

Systemair LDC Circular Silencer 200mm Dia x 600mm Long

Systemair LDC Circular Silencer 200mm Dia x 600mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 200mm Dia x 600mm Long

200mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£113.99

Systemair LDC Circular Silencer (100mm Dia) - eFans Direct Ltd -8180 – 5188 - 5189 -5996

Systemair LDC Circular Silencer (100mm Dia) - eFans Direct Ltd -8180 – 5188 - 5189 -5996

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 100mm Dia x 1200mm Long

100mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£132.99

Systemair LDC Circular Silencer 125mm Dia x 1200mm Long

Systemair LDC Circular Silencer 125mm Dia x 1200mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 125mm Dia x 1200mm Long

125mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£134.99

Systemair LDC Circular Silencer 200mm Dia x 900mm Long

Systemair LDC Circular Silencer 200mm Dia x 900mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 200mm Dia x 900mm Long

200mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£149.99

Systemair LDC Circular Silencer 250mm Dia x 300mm Long

Systemair LDC Circular Silencer 250mm Dia x 300mm Long

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 250mm Dia x 300mm Long

250mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£151.99

Systemair LDC Circular Silencer 250mm Dia x 600mm Long

Systemair LDC Circular Silencer 250mm Dia x 600mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 250mm Dia x 600mm Long

250mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£161.99

Systemair LDC Circular Silencer 315mm Dia x 600mm Long - eFans Direct Ltd

Systemair LDC Circular Silencer 315mm Dia x 600mm Long - eFans Direct Ltd

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 315mm Dia x 600mm Long

315mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£178.99

Systemair LDC Circular Silencer 250mm Dia x 900mm Long

Systemair LDC Circular Silencer 250mm Dia x 900mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 250mm Dia x 900mm Long

250mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£187.99

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDR 30-15 Rectangular Silencer 300 x 150 x 950

300 x 150 x 950mm
Rectangular duct silencer
Universal PG/Metu flange

In stock

Next day delivery available

£207.99

Systemair LDC Circular Silencer 315mm Dia x 900mm Long

Systemair LDC Circular Silencer 315mm Dia x 900mm Long

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 315mm Dia x 900mm Long

315mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£238.99

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDR 40-20 Rectangular Silencer 400x200x950mm

400 x 200 x 950mm
Rectangular duct silencer
Universal PG/Metu flange

In stock

Next day delivery available

£246.99

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDR 50-25 Rectangular Silencer 500 x 250 x 950

500 x 250 x 950mm
Rectangular duct silencer
Universal PG/Metu flange

In stock

Next day delivery available

£317.99

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDR 50-30 Rectangular Silencer 500 x 300 x 950

500 x 300 x 950mm
Rectangular duct silencer
Universal PG/Metu flange

In stock

Next day delivery available

£329.99

Systemair LDC Circular Silencer 355mm Dia x 900mm Long - eFans Direct Ltd

Systemair LDC Circular Silencer 355mm Dia x 900mm Long - eFans Direct Ltd

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDC Circular Silencer 355mm Dia x 900mm Long

355mm dia
Circular duct silencer
50mm insulation

In stock

Next day delivery available

£355.99

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Systemair LDR Rectangular Silencer - eFans Direct Ltd

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair LDR 60-30 Rectangular Silencer 600mm x 300mm (Length 950mm)

600 x 300 x 950mm
Rectangular duct silencer
Universal PG/Metu flange

In stock

Next day delivery available

£364.99

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