Help.. Loud droning noise at high revs

[rageyg]

Hi all, been on here for a while now without posting.

Currently own a Subaru heritage 99 auto, Everything stock except for 18" b spec rims and headlights.

Today had to replace battery, replaced air filter and headlights. Simple jobs, got them done no problem took it out for a spin and now
The car seems to be making louder droning noises then usual at higher revs, got home lifted up the hood to check that all the hoses are attached properly to air filter
Yep all good... Took her out for a spin again and same thing

Any have any ideas as to why?

Any help would be much appreciated, Thanks Geoff

[Robbks]

check the entire intake pipe.
you may have knocked off one of the breathers or resonator chambers.

[rageyg]

Checked pipe took entire thing off, put back together still same thing.

I dont mind the sound, just want to know if it is damaging anything.

[Dropz]

Is the air cleaner box fitted correctly?

[AlpineRaven]

Sound like there is a leak somewhere!
Cheers
AP

[mitchy_bobby]

Is the air cleaner box fitted correctly?

Double check this, it can be easily missed. i changed the air filter and the bottom of the box wasn't closed properly. made it really loud.