Start with low volume, especially with headphones: pure tones and swept frequencies sound significantly louder than music at the same level.
How it works
Covers both sides of the audio. On the input side, it opens the chosen microphone and displays the real-time level in percentage and full-scale relative decibels, along with the waveform and frequency spectrum, so you can instantly see if the microphone is picking up, clipping, or just picking up background noise.
Test recording is the most honest way to hear yourself: you record a few seconds and play them back as the other person receives them on a video call. You can also turn echo cancellation, noise suppression, and automatic gain control on or off to compare how the sound changes with each processing.
On the output side is a tone generator with configurable frequency, volume and waveform, independent testing per left and right channel, and a 20 Hz to 20 kHz sweep that runs through the entire audible range to detect muted speakers, distortion or hum.
Examples
-12 dBFScorrect voice levelSpeaking normally, it is advisable to move between -18 and -6 dBFS: with peaks that touch 0, the audio is clipped and sounds distorted.440 Hzthe note the referenceIt is the tone with which the instruments are tuned and a good starting frequency to verify that both speakers sound the same.20 Hz → 20 kHzsweep of entire audible rangeNotebook speakers hardly play below 150 Hz, and above 15 kHz many adults no longer hear anything: both things are normal.Use cases
- Check your microphone and headphones before a meeting or online class.
- Hear how others hear you and adjust the distance to the microphone with the level meter.
- Detect a mute or inverted channel on speakers or sound equipment.
- Discover electrical hums and noises by observing the spectrum with the environment silent.
- Check to what frequency some headphones reach or how far your own hearing reaches.
Frequently asked questions
Can you hear what the microphone picks up?
No, and it's on purpose: returning the microphone to the speakers generates feedback that ends in a very annoying beep. What you see is the live measurement; To listen to yourself, use the test recording, which reproduces exactly what you captured.
What do negative decibels mean?
In digital audio 0 is the maximum possible, so all useful levels are negative. A normal voice should range between -18 and -6 dBFS. If the level hits 0 constantly, the signal is clipped and distortion appears.
Is it advisable to leave noise suppression activated?
For meetings yes: remove the fan, air conditioning and typing. To record voices or instruments, it is best to turn it off, because the processing cuts highs and produces that typical metallic sound. Try both options and compare the recordings.
Why can't I hear the lowest or highest tones?
For two reasons that add up. Small speakers cannot reproduce low frequencies—those in a notebook rarely go below 150 Hz—and human hearing loses treble with age: at age 40 it is common not to go below 15 kHz. Use headphones to separate one factor from the other.
Can I choose which output the tone sounds through?
The tone is sent to the system's default output, so if you want to try another device, change it from the operating system's sound settings. What you can choose here is the channel: left, right or both.