For a first timer to Meshuggah what album do you think I should start with?
That's a tricky one to answer. I'll try and quickly go over Meshuggah's history and direction and then depending on your taste you could drop in where you feel is most accessible for you based on what you already listen to, because certainly for the last 20 years, different Mesh albums have been like the same pizza with slightly different toppings.
Sooo, they started off as a kind of slightly odd thrash band; their really early stuff was somewhat And Justice For All-like, here's a song off their debut album from like 1991 or something:
They started to find their sound with the None EP, picking up the 7 string guitars, incorporating slightly more odd time signatures and Holdsworth-esque solos. At the time this was a whole new thing to people listening:
Then came Destroy. Erase. Improve in 1995 where they really found their own sound and identity, whilst still holding onto to some of those thrash roots:
The next album, Chaosphere in 1998 is where they really started just sounding like Meshuggah; cold, mechanical and relentless but with grooves hidden among all the confusing rhythms. This was also the last album to have any semblance of their thrash origins:
Then came Nothing in 2002 marking the start of what has remained the recognisable Meshuggah 'Djent' so often imitated. Out came the 8 string guitars and the tempo of the songs was noticeably slower, simpler and groovier. This album actually came out twice, since the band weren't happy with the gear and mix, and re-recorded it in 2006:
There was the I EP, which is one EP length song, not a first-timer's thing so I'll skip that, then Catch 33 in 2005 which is really an album-length song broken up into different titles. It's one of my favourite things they've done, but it very much focuses on the repetitive and meditative aspect of their sound so some people can find it a bit boring but for me it's an experience sort of thing and I love it (not a Spotify playlist item).
After that from 2008 to now you have Obzen, Koloss and The Violent Sleep of Reason, which are all pretty similar - they got harder and more complicated again, experienced with a slightly more organic sound (kinda Nothing mkII, my least favourite along with I) and then their last one was somewhere in between those two
No matter what album you pick...
Jens - screams like Jens. All the time.
Melody - minimal if absent
Polyrhythms - standard