Most phones have dual speakers that get reasonably loud — until you’re in a noisy restaurant, a car, or trying to share a video with someone across the table and then “reasonably loud” isn’t enough. The good news: you can get a meaningful jump in volume out of the phone you already own, with no accessories and no cost. I measured mine with a decibel meter before and after, and the difference was bigger than I expected. Here’s what actually moved the needle.
Use physics to instantly make your phone speaker louder
Reflect sound waves with your hand or with a cup — it really works!
If you place your phone’s bottom-firing speaker against the corner of a wall, or you put your phone in a cup or mug (seriously), you can significantly amplify the audio coming out of your phone. This is because you’re reflecting the sound waves of your phone back into the room, instead of letting them get absorbed (and silenced) by the walls or floor. Not only that, but the cup is acting as a passive resonator/horn that directs sounds towards you. It really works, and placing my Pixel 10 Pro in a mug while playing audio made my phone almost as loud as a modest Bluetooth speaker, though with less bass, and certainly not as loud as the Ultimate Ears Everboom.
Using your hand also works
You can also use this amplification technique in personal contexts by just cupping your hand around the bottom of your phone’s speaker. This is perfect for amplifying a phone call, or sharing an audio track with a friend in a loud environment.
The next tweak is a quick software setting you can change to make audio sound louder.
Switch to mono audio output
Hear an immediate boost in volume
When phones with dual speakers play sound, these speakers do not play the same sound; instead, they play in stereo which separates the right channel from the left, which music producers utilize to make the sound seem more lively (often audio engineers will put vocals in one channel and instruments in the other to produce a wider sound stage).
This fancy audio engineering is fine if you’re using high-end headphones (though good-enough headphones count too) or big external speakers, but on your phone’s little speakers, stereo audio playback limits your volume.
You can stop your phone from playing stereo audio by having your phone only playback audio in mono audio and have both speakers play the same audio track. Sure, the sound might be a bit flatter if you turn on mono audio, but you’ll get more volume. In mono, both speakers play the same full signal output, so you get the summed output of both drivers.
To do this, go to Settings > Accessibility > Audio adjustment (on Samsung phones it’s Hearing enhancements) > Mono > Turn On.
The next thing you can do to make your phone louder is by adjusting the volume of individual frequencies in the equalizer.
Boost mids and highs
Adjust the equalizer
Any audio that you hear playing is composed of multiple frequencies. Low frequencies produce bass, and while they actually travel farther through walls and open space, your ears aren’t especially sensitive to them. Human hearing peaks in the mid-to-high range — roughly 2kHz to 5kHz — which is why boosting those frequencies makes audio sound louder even though the phone isn’t pushing more total power.
On some devices, particularly on Samsung phones, you can customize the audio equalizer, which dictates how your phone treats different frequencies. If you don’t have access to an equalizer on your phone, try Echo Equalizer. You can tell your phone to play certain frequencies louder by adjusting the equalizer, which makes your audio seem louder because it emphasizes the mid-to-high range your ears are most sensitive to.
To change the equalizer on your Samsung phone, go to Settings > Sound and vibration > Sound quality and effects > Equalizer > Custom.
Then you’ll see a series of adjustable lines you can tweak. The lines on the left are your lower frequencies, and the lines on the right are your high frequencies. To make your phone louder, we are going to focus on the 1k-16k lines, which is where your middle/high frequencies are.
Boost these almost all the way up. If you’re playing an audio source, you can hear the difference in real time as you adjust the equalizer. Adjusting any slider all the way to the top might make the sound unbalanced and harsh, so bring each slider within 1k-16k to at least 60%, or up to 80%.
My speaker is so much louder now
I gained 15 decibels
Using a decibel meter, I measured my Pixel 10 Pro jumping from about 70dB to 85dB — mostly from switching to mono and propping the phone in a mug. That’s a 15-decibel gain, which sounds roughly two to three times louder to your ears. For 85dB context, that’s about the level of a noisy restaurant or city traffic — loud enough that it’s also where prolonged exposure starts to risk your hearing, so use max volume in short bursts. Not bad for a few free tweaks!