OM616, engine sound diagnostics

[Nauti]

Hello!

So today I've put my 300D from -77 in its winter hibernation place. Yesterday I was sitting by my computer and watching Kent talking about a good engine sound and came to think of mine. I tried comparing it today and the engine is something I've always felt I can't communicate with. The rest of the car speaks and it's somewhat easy to identify what sound is coming from where. But this car makes so many noises and I have no real clue of what is a bad sign and what is a robust old Mercedes sound. Here's a short video of me starting up my engine and some sound of it running (cold): Someone told me it's arrythmic and myself I found the knocking sounds a tad alarming. But I thought I needed to ask someone who actually knows their **** so to speak, so of course this forum came to mind

I did the valve adjustment a little over a year ago and I haven't driven much since, but I have no clue if the timing chain is worn and I thought about checking that next year. I simply want to know if I need to worry, how much I should worry and about what more specifically x)