Water ON causing a Throbbing Noise

Water ON causing a throbbing Noise
I have a foreclosed house. I got the water turned ON and have city installed a new Water Meter. I sealed the leaking valves and shut of non tap valves. Now when I turn out the water the noise is loud that neighbor came and ask if I needed help. If I try a few timees turning off and then turning ON after a while I get a chance that tap opens without noise. I shut down and start and it does the same. Does it have Air traped or fault meter? How do I get the air out? I tried having water ON next to the Water heater but no luck ...

You either have a worn valve or a worn toilet fill valve, in all likelihood.

Check the toilets by turning off each one at the valve under the toilet, then see if the noise has stopped. Otherwise, it may be a loose gate in a gate valve or a loose washer in a globe valve. Those are the most common culprits of vibrating water hammer.

Throbbing/ Hammer Noise

Can you please explain me what do you meany by loose gate in a gate valve?
OR loose washer in a globe valve?
No idea what is Gate or Globe valve.
No Noise when toilet fills, Its when I open any tap. (Could be hot water causing it?)

A gate valve has a plate or gate that is attached to the valve stem. It raises or lowers to turn water on or off. The gate is rides in tracks on each side. This could be vibrating.

A globe valve has a plug that lowers into a seat that shuts the water off.

noise

There are many possible causes for the noise, starting with a bad faucet or valve. You may need a plumber if you cannot determine WHERE the noise is coming from.

Hammering Not initially only ..

After replacing lot of valves and able to open all faucets. hopefully took all air out. Now I get a hammering sound for a few seconds when we open almost any tap but then quickly dies. How to fix the initial hammer sound? Any help would be appreciated ...