is there a boot sound on new mac Mini?

Nope' see > About Mac startup tones - Apple Support

No the boot chime was eliminated a couple of years ago.

Here is a link to enable Start up Chime.

Bring back your Mac's startup chime in two easy steps - CNET

Actually it is the same as John Lockwood has posted, just different site.

As indicated by macjack and den.thed Apple a few years ago 'removed' the startup sound.

Conspiracy theorists attributed this either Apple post Steve Jobs becoming ever more 'boring' or bean counters saving 0.0000001cents per Mac by needing less on board ROM space by deleting this. (Obviously Apple are financially suffering and have hundreds of billions of dollars of debt, of course they also have hundreds of billions of dollars of cash and short term investments.)

However I came across the following article literally in the last week!

https://eclecticlight.co/2020/02/22/how-to-enable-the-startup-chime-on-recent-macs/

Based on the above article it seems 'boring' was the true cause.