I Blind-Tested 5 AI Mastering Services Against a Human Engineer. Here's What Happened.
Guest Post by Josh Gilliland, Founder of JG BeatsLab
I took three Suno-generated tracks — Hard Rock, Country, and Soul — and ran them through five commercial AI mastering services:
Masterchannel, and
MIXEA (DistroKid's built-in option)
Then I mastered the same tracks myself in Reaper as the human benchmark.
Every version was measured technically (loudness, true peak, dynamic range, clipping) and evaluated blindly by two independent AI listening agents who didn't know which was human and which was automated.
The headline: the human master won every genre. Both listening agents ranked it first across all three tracks.
But the more useful finding is why.
AI mastering delivers loudness and brightness. That's what the algorithms optimize for. The human master was the only version that expanded dynamic range — restoring the breathing room that makes a track feel alive instead of flat. That's not talent. It's intent — making surgical, genre-specific decisions that no algorithm attempted.
The other finding that should concern creators: two of the five services delivered files that clip above 0 dBTP. That's digital distortion baked into your final master.
One of them produced 131 clipping instances across three tracks while also being the quietest master in the test — maximum damage, minimum loudness. If you're using a bundled mastering tool and going straight to distribution, you may be releasing clipped files without knowing it.
Not all AI services are equal though. One stood out with zero clipping, safe true peaks, and competitive loudness.
The price difference between services is small, so choose based on quality, not cost.
The quick safety check every creator should run before releasing anything:
True Peak: below -1.0 dBTP (above 0 = clipping)
Dynamic Range: above 5.0 LU is healthy
Integrated Loudness: -14 to -9 LUFS for streaming
A free loudness meter like Youlean takes 30 seconds and will catch problems before your listeners do.
— Josh Gilliland, JG BeatsLab
Josh writes about AI music production — how to use the tools, how the platforms compare, and how to turn AI-generated tracks into professional releases. His books and production guides are at jgbeatslab.com/music-books
