For starters, the internal storage on the new Mac mini is user replaceable. Nobody’s sure yet whether you’ll have to buy an upgraded chip from Apple but probably someone will figure out how to do this. And quite honestly attached storage is so fast most audio/visual users use an attached SSD.

However, the benchmarks of the M4 are so much better than PC competitors that even if you spend another $400 on an internal 1TB SSD, it still beats its competitors. Personally I’d add a big external SSD and if I wanted to upgrade, I’d get more RAM. $200 would get you 24GB RAM, but the only reason you might need that for audio production is running huge orchestral libraries, and I rather doubt anyone here is doing that.

You really should watch some of the YouTube videos. Even the barebones base mini is gobsmacking testers with how it laughs at insane workloads, far beyond anything we’re going to throw at it. We’re not 4K 3D game developers, or working with 8K multiple video editing. Audio is laughably easier on computers compared to that.

For what we do, even the $600 base model is massively overpowered. And compared to its PC competitors that you’d need to pay well over twice the price for equivalent performance (even though you’d get more storage internally), you get Apple’s rock solid OS and no intrusive Windows bloat and vulnerability. It’s also an emulation powerhouse, so you can run Linux, Windows and other niche OS’s if you need to, at impressive benchmarks.

Most testers are calling the base model the best bang for the buck currently available by quite a margin..!
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An arranger is just a tool. What matters is what you build with it..!