Guides

The 350 Hz problem: why AI tracks sound boxy, and how to clean the low mids

Updated 2026-09-06

Play a generated track on headphones and it sounds fine. Play it in a car or on a phone speaker and the whole thing turns into a wool blanket. Nine times out of ten the cause is a few decibels too much between 250 and 450 Hz.

Why it is there

That band is where the body of almost every instrument overlaps: the low end of a vocal, the high end of a bass, the fundamentals of guitars and keys. A generator produces each part with a full body of its own and does not carve space between them the way a mixer would. The overlaps add up. On a spectrum the result is a broad hump centered near 350 Hz, typically 3 to 6 dB above a commercial reference in the same genre.

How to hear it

Sweep a narrow EQ boost slowly from 200 to 500 Hz. Where the track suddenly gets honky or boxy, that is the center. Then turn the boost into a cut.

How much to cut

• Start at -2 dB, a bandwidth of about one octave, centered where the sweep found it.
• Go to -4 dB only if the analyzer shows the hump is that large. Past -5 dB the track starts to sound thin.
• Do it before compression. A compressor reacts to the mud and pumps on it.
• Check in mono on a phone speaker. That is where the cut pays off.

What Burnish does

It measures the low-mid band against the genre target, cuts only the excess, and prints the center frequency and the depth in dB on the report. If the file does not have the problem, it does not cut. The free analysis shows you the number before you decide.