Mysterious sound coming from basement, related to water pipes
It's probably just the pipes expanding and contracting under temperature changes. They can bind on an anchorage, then suddenly break loose. The floor and pipes do reverberate, amplifying the sound. The tension release and sudden movement can be very small, yet the resulting sound rather startling.

If you can identify where the pipe is hanging up, you can replace the anchor with one that has a plastic liner that is resistant to binding. Or simply loosen the anchor or remove it, wrap the pipe with cloth tape, then reinstall the anchor.

It can be difficult to locate all the pops and creaks, they seem to come from nowhere sometimes. You should at least be able to quiet the worst offenders.