Set Your Audio Output Level Correctly
February 2017 – by Per Christensson
When you connect an audio output device to a powered speaker, you may have to control multiple volume settings. For example, if you connect your smartphone to an amp, you might need to set the volume on both the phone and the speaker. So what are the ideal volume settings?
Generally speaking, you should set the main device's audio output somewhere between 80 to 90%. This should provide a solid "line out" level, which doesn't attenuate the original signal, but also doesn't add extra gain. Some devices can add +6 or even +20dB gain to the signal when cranked up to 100%, which will most likely produce a distorted signal.
Most powered speakers have better and more powerful preamps than your phone, you should use the speaker's amp to boost the signal rather than the phone. But you don't want to limit the audio input coming into the speaker, which is why a volume setting around 80% on your phone is a good balance. Below is an example of where I might set my iPhone volume when connecting it to an external speaker.
Summary: Set the volume level to 85% on your phone, then adjust the speaker volume to control the overall sound amplitude.
What about digital audio output?
When connecting digitally to an audio output device (like a USB or Bluetooth connection), the volume might be fixed. You can tell if the output is fixed if changing the volume on your phone, computer, or other device has no effect on the sound level. This means the digital connection is automatically using a standard line level signal between your music-playing device and the speaker. All you need to do is control the volume on the speaker, which makes it pretty simple.