# Why Does My Master Sound Thin? > Thin usually means one of four things, and only one of them is a mastering problem. How to tell them apart in two minutes and which to fix where. [All guides](/blog) # Why Does My Master Sound Thin? Published 24 August 2026, 15:00 UTC · updated 12 August 2026, 21:30 UTC · by Loopin A thin master is almost always a mix that was thin before it got there. Four causes, and the two-minute test that tells you which one you have. ## First: is it thin, or is it just not loud? Turn the master up until it matches the reference track you are comparing against. A large share of "thin" is a level difference — quiet material sounds thinner because human hearing loses low end at low volume, not because anything was removed. Only judge tone at matched level. This one step resolves the complaint outright more often than any processing change. ## Cause one: over-aggressive high-passing in the mix High-passing every channel at 100 Hz is common advice and it removes the body along with the mud. By the time twenty tracks have each lost their low mids, the mix has no weight left and no mastering move puts it back — you cannot boost what was not printed. High-pass what genuinely needs it and leave the rest. Bass, kick, and anything with body in the 100–250 Hz range usually needs less filtering than people apply. ## Cause two: the 200–400 Hz scoop This range is where warmth lives, and it is also the first place people cut when a mix sounds muddy. Cutting it makes a mix sound cleaner in isolation and thinner in every real listening environment, especially phones and laptops which have nothing below 200 Hz at all. If you scooped it, put half of it back. A mix that sounds slightly thick on studio monitors usually sounds right everywhere else. ## Cause three: over-limiting flattened the low end The limiter reacts to the loudest thing in the signal, which is almost always the bass and kick. Push it hard and the low end is what gets reduced, so the record becomes thinner as it gets louder — the exact opposite of what was intended. The tell is that the thinness appears in the loudest sections and disappears in the quiet ones. Lower the loudness target rather than adding low-end EQ to compensate, which just makes the limiter work harder on the same material. ## Cause four: mono bass, or the lack of it Wide low frequencies partially cancel when summed to mono, and a lot of playback is mono — phone speakers, most Bluetooth speakers, many club systems. A mix with stereo width below about 120 Hz can lose most of its weight the moment it is summed. Check by summing to mono and listening for the low end vanishing. [Master the track](/mastering) from a mix with the bottom end centred, and compare against [the other common master complaints](/blog/why-does-my-master-sound-distorted) if more than one symptom is present. ## Frequently asked questions ### Why does my master sound thin compared to commercial tracks? Match the levels first — most of the complaint is volume, since hearing loses low end at low playback levels. If it persists at matched level, the usual causes are over-high-passing in the mix, a scoop around 200-400 Hz, or over-limiting. ### Can mastering add low end that is not there? Only a little. Boosting works on what was printed; if twenty channels were each high-passed at 100 Hz there is nothing left to raise. Thin masters are usually thin mixes. ### Why does my track get thinner as it gets louder? The limiter is reacting to the bass and kick, which are the loudest things in the signal, so the low end is what gets reduced. Lower the loudness target rather than adding low EQ to compensate. ## Related reads - [Master your track free](/mastering) - [Why does my master sound distorted?](/blog/why-does-my-master-sound-distorted) - [How to prepare your mix for mastering](/blog/prepare-your-mix-for-mastering) --- Source: https://onloopin.com/blog/why-does-my-master-sound-thin