Why the louder EQ always sounds better

Switch on an equalizer and it usually sounds better straight away, before you have touched a single band. Some of that is real. A lot of it is volume. Here is what is going on, and how to tell the two apart in under a minute.

Turn it up and everything sounds better

Play the same song quietly, then turn it up. It does not just get louder. It seems to gain low end, gain air, and sound more finished. People describe it as the music waking up.

That is not imagination, and it is not the speaker changing. It is your hearing.

Your hearing is not flat, and it moves

A pure tone has to be louder in the deep bass and the very high treble than in the midrange before it sounds equally loud. Plot those points for every frequency and you get an equal-loudness contour. The curves were first measured by Fletcher and Munson in the 1930s, and they were later re-measured and standardised. The current reference is ISO 226, Normal equal-loudness-level contours, in its 2023 edition.

Two honest points about it. First, the standard covers pure continuous tones only; it does not claim to describe music, so treat it as the mechanism behind what you hear rather than a formula for it. Second, the standard descends from the Robinson and Dadson measurements of the 1950s, not from the famous Fletcher and Munson curves, even though that older name is the one usually quoted.

The practical part is simple. As you turn the volume up, the bass and treble you perceive rise faster than the midrange does. So a louder version of the same recording genuinely sounds richer. It is not a trick played on you by the app. It is how hearing works.

Which is why every EQ sounds better switched on

Now put that together with how audio apps behave. Add a filter, and the level usually goes up a little, because a boost adds energy and the maker wants the button to feel like it did something. Compare the two states without matching level and the louder one wins almost every time.

This is well known in audio work, and the rule that follows from it is blunt: match the loudness before you judge anything. Professionals treat an unmatched comparison as no comparison at all. If you did not match the level, you did not hear the processing. You heard the volume.

It cuts both ways, too. Measured properly, the link between loudness and preference is not simple. In one controlled test, a jazz track scored better when it was turned up while an electronic track scored better when it was turned down. Loudness is a strong bias, not a law of nature.

Check it yourself, in about a minute

You can hear the effect on this site without installing anything: the two-button test plays one recording, tells you one side is 3 dB louder, then lets you match the loudness and hear the difference collapse.

To check an equalizer instead, do this:

1. Set every band flat.
2. Play a track you know well.
3. Toggle the app on and off while it plays.
4. Listen for a change in level before you listen for a change in tone.

At flat, there should be no level change at all. If flat is louder than off, the app is adding gain before you have asked for anything.

What Earwave does about it

Earwave is built so the honest comparison holds up. With every band at 0 and Loudness off, its output matches bypass sample for sample: no hidden level, no colouring. Each preset is level-matched to Flat, within half a dB, measured through the engine, so switching between them keeps the same loudness instead of rewarding whichever one is loudest. The peak limiter holds the ceiling down when you boost rather than letting the boost distort.

Loudness is the one feature that changes the tone with level, and it is meant to. Earwave's Match my volume switch applies the ISO 226 contour at the level you are actually listening at, worked out from your Mac's volume and Earwave's own. Quiet listening gets back the bass and treble your ears lose, and the lift fades as you turn up. To keep that lift from clipping, Earwave also lowers the overall level by the lift's peak and says so on screen, so it cannot win a comparison by being louder.

None of that makes for a dramatic demo. That is the point. An equalizer should change what you asked it to change, and nothing else.