--- title: How to reduce noise from your bow thruster description: Noisy thruster? Whether there has been a lot of noise from day one, or if the noise level has gotten worse over time, there are ways to fix this. image: https://blog.sleipnergroup.com/hubfs/Skjermbilde%202020-03-26%20kl.%2017.21.24.png --- [![Side Power by Sleipner](https://blog.sleipnergroup.com/hs-fs/hubfs/Logos/Side_Power_by_Sleipner_R_300px.png?width=214&name=Side_Power_by_Sleipner_R_300px.png "Side Power by Sleipner")](https://blog.side-power.com/en?hsLang=en) ![](https://blog.sleipnergroup.com/hubfs/Template%20Files/Flags/EN-01.png) [![](https://blog.sleipnergroup.com/hubfs/Template%20Files/Flags/NO-01.png)](https://blog.side-power.com/no?hsLang=en) [![](https://blog.sleipnergroup.com/hubfs/Template%20Files/Flags/SE-01.png)](https://blog.side-power.com/se?hsLang=en) [![](https://blog.sleipnergroup.com/hubfs/Template%20Files/Flags/DE-01.png)](https://blog.side-power.com/de?hsLang=en) [![](https://blog.sleipnergroup.com/hubfs/Template%20Files/Flags/IT-01.jpg)](https://blog.side-power.com/it?hsLang=en) ![Pier talk_EN_72dpi](https://blog.sleipnergroup.com/hs-fs/hubfs/Template%20Files/New%20blog%20header/Pier%20talk_EN_72dpi.png?width=600&name=Pier%20talk_EN_72dpi.png) - [Latest posts](https://blog.sleipnergroup.com/en) - [Marine Stabilizers](https://blog.sleipnergroup.com/en/category/marine-stabilizers) - [Marine Thrusters](https://blog.sleipnergroup.com/en/category/marine-thrusters) - [Marine Hydraulics](https://blog.sleipnergroup.com/en/category/hydraulic-thrusters) # [How to reduce noise from your bow thruster](https://blog.sleipnergroup.com/en/how-to-reduce-noise-from-your-bow-thruster) By [Runar Scott Jensen](https://blog.sleipnergroup.com/en/author/runar-scott-jensen) 2. May 2019 - [Tweet](https://twitter.com/share) #### ![cavitation causing air bubbles thruster](https://blog.sleipnergroup.com/hs-fs/hubfs/Skjermbilde%202020-03-26%20kl.%2017.21.24.png?width=1083&name=Skjermbilde%202020-03-26%20kl.%2017.21.24.png) #### Does your bow thruster make a lot of noise? Whether there's been a lot of noise from the day it was installed, or if the noise level has evolved over time, there are ways to fix this.  ## Reduce vibration and noise from the hull during installation It is no secret that some boats are built better than others. Every hull has its own resonance frequency, which serves to either amplify or mute thruster noise. "Structure-borne noise" is the noise that travels through the boat's own structure. The inner liner that often acts as a form of "loudspeaker membrane," for example, could potentially be reinforced and strengthened. Anything your installer can do here, to further isolate the transferral of noise and vibration is going to help. Read more: [Pros and cons of different marine thrusters →](https://blog.sleipnergroup.com/en/pros-and-cons-for-different-types-of-marine-thrusters?hsLang=en) ## Reduce cavitation A general rule of thumb is always to choose the largest tunnel diameter you can possibly fit into your boat. Fitting a larger than normal diameter tunnel, for example, will not only increase thrust efficiency but will also create a freer water-flow area that itself will help to reduce noise. Similarly, where the tunnel ends meet each side of the hull, instead of leaving sharp, 90-degree style corners, simply by rounding off and smoothing off the edges will not only increase thrust efficiency, but the reduced turbulence and cavitation caused from the propellers will also reduce overall noise. The video below illustrates this rather well:      ## Consider changing to a low noise propeller Check if new [composite low noise propellers](https://side-power.com/kategori/1897/propell-oppgradering/) are available as a retrofit to your thruster brand. The dominant noise frequency of a typical installation is nearly always the result of propeller tip designs, so any improvements here can make quite a big difference. The best of these low noise props has 5 blades with a "skew" blade profile that gives less frequent noise "peaks" by slicing through the water with a longer leading edge when compared to more traditional propeller designs. Read more: [How much power do I need from my bow and stern thruster installations? →](https://blog.sleipnergroup.com/en/how-much-power-do-i-need-from-my-bow-and-stern-thruster-installations?hsLang=en) Simple rules of physics tell us that, in most cases, low RPM = low noise. Therefore, it is far better to over-specify power and use it in conjunction with a decent Proportional Control System. ## Gradually Adding Thrust with Proportional Power Control  [Proportional Power Control](https://side-power.com/kategori/1896/dc-speed-control/) enables the user to feed in power gradually using just the right amount of thrust to position a boat anywhere you want it to be, in every kind of mooring situation. Used correctly with a suitably powerful thruster on a low-power setting, PPC can, in fact, be almost undetectable to the human ear. Read more: [How to choose the best thruster brand for your boat →](https://blog.sleipnergroup.com/en/how-to-choose-the-best-thruster-brand-for-your-boat?hsLang=en) Hopefully, within this short article, we’ve shown you that a few carefully considered steps and upgrades are all it takes to reduce noise from thrusters and benefit from the confidence, control and greater boating enjoyment they can give you.   [![Get access to files and technical drawings](https://no-cache.hubspot.com/cta/default/4156488/3c601bf5-d576-4f06-9bb0-b4c2a79093af.png)](https://cta-redirect.hubspot.com/cta/redirect/4156488/3c601bf5-d576-4f06-9bb0-b4c2a79093af) Topics: [thrusters](https://blog.sleipnergroup.com/en/topic/thrusters?hsLang=en), [reduce noise](https://blog.sleipnergroup.com/en/topic/reduce-noise?hsLang=en), [Side Power](https://blog.sleipnergroup.com/en/topic/side-power?hsLang=en), [Marine Thrusters](https://blog.sleipnergroup.com/en/topic/marine-thrusters?hsLang=en), [Boat Owners](https://blog.sleipnergroup.com/en/topic/boat-owners?hsLang=en) ![Runar Scott Jensen's photo](https://blog.sleipnergroup.com/hubfs/People/Runar_S_Jensen_02_2016.jpg) By: [Runar Scott Jensen](https://blog.sleipnergroup.com/en/author/runar-scott-jensen) Runar Scott Jensen has been in the marine business for more than 22 years and has a broad experience with technical equipment. Runar holds the position of Norwegian Sales Director at Sleipner Motor. Like many other employees at Sleipner, Runar is often at sea himself, learning firsthand the importance of reliability while boating. Welcome to Pier Talk – a place for boaters, by boaters.   Here we share our expert knowledge and guidance on boat equipment, tips for maintenance, as well as practical experiences about life at sea.   Stay up to date by signing up for the topics you find interesting ☺️   Side-Power is a world-leading manufacturer of thrusters and stabilizer systems for recreational boats, yachts, and commercial vessels up to 160 feet/ 50 meters.   Explore [side-power.com](https://side-power.com) ### Recent posts ### Posts by topic - [Boat Owners (11)](https://blog.sleipnergroup.com/en/tag/boat-owners) - [Marine Thrusters (9)](https://blog.sleipnergroup.com/en/tag/marine-thrusters) - [Marine Stabilizers (8)](https://blog.sleipnergroup.com/en/tag/marine-stabilizers) - [Industry Professionals (6)](https://blog.sleipnergroup.com/en/tag/industry-professionals) - [Thruster - Leisure (5)](https://blog.sleipnergroup.com/en/tag/thruster-leisure) - [Vector fins™ (5)](https://blog.sleipnergroup.com/en/tag/vector-fins) - [Marine Hydraulics (4)](https://blog.sleipnergroup.com/en/tag/marine-hydraulics) - [thrusters (4)](https://blog.sleipnergroup.com/en/tag/thrusters) - [bow thruster (3)](https://blog.sleipnergroup.com/en/tag/bow-thruster) - [stabilizers (3)](https://blog.sleipnergroup.com/en/tag/stabilizers) - [anti roll (2)](https://blog.sleipnergroup.com/en/tag/anti-roll) - [hull design (2)](https://blog.sleipnergroup.com/en/tag/hull-design) - [stern thruster (2)](https://blog.sleipnergroup.com/en/tag/stern-thruster) - [DC Speed Control (1)](https://blog.sleipnergroup.com/en/tag/dc-speed-control) - [Safety (1)](https://blog.sleipnergroup.com/en/tag/safety) - [Seasickness (1)](https://blog.sleipnergroup.com/en/tag/seasickness) - [Side Power (1)](https://blog.sleipnergroup.com/en/tag/side-power) - [Thruster - Work boats (1)](https://blog.sleipnergroup.com/en/tag/thruster-work-boats) - [Yachting (1)](https://blog.sleipnergroup.com/en/tag/yachting) - [customer service (1)](https://blog.sleipnergroup.com/en/tag/customer-service) - [fin stabilizer (1)](https://blog.sleipnergroup.com/en/tag/fin-stabilizer) - [gyro stabilizer (1)](https://blog.sleipnergroup.com/en/tag/gyro-stabilizer) - [proportional control (1)](https://blog.sleipnergroup.com/en/tag/proportional-control) - [reduce noise (1)](https://blog.sleipnergroup.com/en/tag/reduce-noise) - [small boats (1)](https://blog.sleipnergroup.com/en/tag/small-boats) - [thruster power (1)](https://blog.sleipnergroup.com/en/tag/thruster-power) - [waves (1)](https://blog.sleipnergroup.com/en/tag/waves) See all topics ### Search Search **Want to know more?**  Visit our stabilizer guide:  Go to our guide here **Explore our stabilizer products** Find the right solution for your vessel.  [See all products here](https://www.sleipnergroup.com/stabilizers/vector-fins?IS_LEISURE=1) Find a distributor Talk to one of our dealers. 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