Hum / vibration over winter... at wits end

[Bolt]

This is your classic 50hz hum, familiar with those who hang out near electrical substations (or use mains hair clippers).

[Bolt]

FWIW, we had a loud irritating noise, that was clearly related to how strong the wind was blowing, that resonated all over the upstairs….. after extensive investigations, it turned out to be a crappy plastic downpipe that resonated in the middle because the support clips were spaced too far apart.

[Lowestoft Firewood]

6 hours ago, doobin said:

You wouldn't generally run an agitator until you are needing to pump it. Individual farms may have different circumstances however.

Smart Slurry Aeration System | Slurry Management | Dairypower

WWW.DAIRYPOWER.COM

---

The Smart Slurry Aeration System is a cost-effective and environmentally friendly way of...

 

 

This is run regularly so you don't have a crust to get rid of. 

[Mrblue5000]

Was thinking the same thing, might be in some of the round slurry stores on the Google image. You may not hear it when leaves are on the trees, or they don’t use it when cows are out.

[thrope]

Thanks a lot, I think we have a winner (or at least current top candidate). Will keep an eye out next spring for cows in the field to see if it stops with that. But I think that explains the seasonality. Still not completely sure why the timing would be as it is (perhaps off peak?) but it does sometimes run in the day, and it does sometimes skip days or go a good few days without hearing it at all, but perhaps that could be atmospheric differences.

 

But otherwise slurry system when the cows are in fits the bill.

[Lowestoft Firewood]

May not stop altogether as still slurry from during milking but much much less. 

[spudulike]

You could try getting in to 70s rock, buying the Mother of all sound systems and knocking yourself out on Zep and Purple....that should hide the annoying noise...pity the neighbours.... unless they like a bit of Rainbow, Gillan Band and Whitesnake! 

[carlos]

if only world leaders had this diligence to solving problems!!  

[spudulike]

If I was a dictator I would make it compulsory to study the riffs from bands such as UFO, Boston, Rush and ZZ Top. 

[thrope]

Thanks for the suggestions! If I can confirm it is coming from the farm then like I said I think it is to do with the roof resonating because we don't hear it outside. So I would look to change the resonant frequency of the roof by maybe hanging some sandbags off rafters, piling some insulation in the corners or against the gable ends to change the major mode of the space. Any other ideas along those lines welcome!

 

Actually this looks like what I need if I could accurately measure the frequency and build something that matches.

 

Tuned mass damper - Wikipedia

EN.M.WIKIPEDIA.ORG

 

Haven't been able to pick out the frequency. I have a good condenser microphone but I don't think it has sensitivity at 50hz or below (have a feeling the roof might be around 25, so the 50hz power hum might be matching the first harmonic).

 

Thanks again for everyones input, has been really useful and also entertaining.

 

Edited November 1, 2022 by thrope
tuned mass damper