I donāt think anyone else can tell you which youāll prefer, as itās all about what you are trying to achieve, and how you like to work.
The thing with the Elektron sequencer is that you can parameter lock far more with it than anything you can do with an external sequencer.
But to me, using it feels like a very rigid way of āprogrammingā in a track.
I love the modulation options available once you have a pattern built up, but I donāt like the process of getting to that point.
I know there are many people here that start with a pattern/melody in their head and can punch that into the sequencer in only a few moments though.
I have a Torso T1, rather than an Oxi One, and itās so much quicker/easier for me to make progress on a track with that than the Elektron sequencer.
I like it a lot more when it comes to sequencing melodic parts.
But you always have the option of working out your pattern on it, and then recording it in if you arenāt wanting to manipulate it live. That way you can still take advantage of plocks on the Elektron sequencer.
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I have a TR-6S as well, rather than a TR-8S, and itās a very different thing from the Digitakt.
If you want Roland Drums, you canāt do much better. It sounds great thanks to ACB.
But I donāt find it very flexible beyond that. Sure, it does technically have sample playback and sound editing, but I donāt find it to be especially good for either. Itās very menu-divey.
Granted the 8S has a lot more hands-on controls, and eleven tracks vs eight on the DT or six on the 6S.
But for me, its main use is as a āsound moduleā for when I want Roland drums. Thatās part of the reason I went with the much smaller 6S over the 8S.
As a sampler, the Digitakt has so many more possibilities beyond drums.
And while samples are missing something vs ACB or synthesized drums, thereās nothing stopping you from loading up a DT with 808/909 samples etc.
DT has a lot of possibilities to breathe life into them.
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And depending on where you plan on taking things in the future, I donāt think there is anything wrong with having both the Oxi One for sequencing and the Digitakt.
Thereās nothing to say you are only allowed one powerful sequencer in your setup (something the TR-6S/8S certainly does not have).
It may benefit you to pick one sequencer (Oxi) and focus all your efforts on that.
But further down the line, you may find that you want to revisit the Elektron sequencer, have the DT sequencing other gear, or use it for performance control with MIDI CCs mapped out - even if you have an Oxi One sequencing the DT.