Did you know you can calibrate your studio monitors without specialized equipment like measurement microphones, software, or processors? All you need is a computer with a Digital Audio Workstation (DAW).
Professional monitor calibration typically requires a measurement microphone, a processor, and companion software. However, for our purposes, we’ll substitute our ears for the microphone and use your DAW’s equalizer plugin and sine wave generator in place of the processor and software.The Calibration Process:
- Set up your DAW:
- Open your DAW’s built-in sine wave generator (tone generator) on the master bus.
- Immediately after the sine wave generator, insert your cleanest-sounding EQ plugin. A clean EQ is crucial as we aim to subtract frequencies without coloring the sound.
- Arrange both plugins side-by-side on your screen.
- Identify peaks in the low-end:
- Select a sine wave output for the tone generator.
- Slowly sweep the frequency upwards from its lowest point.
- Listen carefully for peaks and valleys in the volume. We’re primarily focused on frequencies up to approximately 400Hz, as room acoustics affect lower frequencies more significantly and can be addressed with an EQ. The most common issues typically occur around 150Hz or below.
- When you hear a peak, sweep the tone generator’s frequency up and down to pinpoint the loudest point.
- Note the frequency on the tone generator.
- Go to your equalizer, select a bell EQ, and reduce the gain at the exact frequency you identified from the tone generator. Start by bringing it down around -3dB.
- Return to the tone generator and sweep that frequency area again. Continue adjusting the EQ until the sweep sounds flat. Don’t hesitate to go as low as -10dB or even -15dB if needed to flatten the volume peak.
- Remember that room geometry creates multiple peaks and valleys. Since extensive acoustic treatment often struggles to fix low-end issues, use the EQ to reduce all the peaks you discover with the tone generator.
- Important Note: Acoustical problems are highly dependent on the Sound Pressure Level (SPL) in the room. The louder the volume, the more pronounced the problems become. Therefore, choose the volume level you use most frequently for this process.
- Address valleys in the frequency response:
- Instead of using a bell equalizer to boost valleys, apply a shelf equalizer at approximately 100Hz with a smooth curve to gently lift the entire low end.
- If previous peaks re-emerge, further reduce the corresponding bell equalizer’s gain or add new bells with larger Q values to address these new, larger peaks.
- While you can use a bell equalizer to address valleys, doing so will significantly shrink the sweet spot for your listening position.
- Be aware that depending on your room and position, you might encounter “dead spots” where specific low-end frequencies cancel themselves out due to reflections. An EQ cannot boost something that isn’t there. To fix this, you’ll need to physically rearrange items in your room.
- Refine and save your settings:
- After adjusting the EQ, import a song you know well into your project and listen to it with the corrective equalizer engaged.
- Experiment with the low and high shelves on the equalizer until you achieve a balance that feels right to you.
- Save this equalizer preset.
- Load this preset onto the master bus for all your projects.
- Tip for Cubase users: You can also use the equalizer in the control room’s output insert slot to ensure it’s always active, regardless of the project.
- Tip for audio interface users: If your audio interface has DSP capabilities and allows for effects on its output, this is an even better solution as it will apply the corrective EQ to all audio playback, including Spotify and YouTube.
Additional Tips:
- Boost Low End without EQ: Pushing your monitors closer to walls can add additional low-end presence. You can then fine-tune this with a low shelf EQ to your preference.
- High-End Adjustment: Use a high shelf equalizer at around 1000Hz to adjust the high-end to your liking.
Investing in Calibration Equipment:
If you decide to invest in equipment for monitor calibration, prioritize products that place the processing as close to the monitor inputs as possible (e.g., a sound card with DSP or a dedicated equalizer box after your audio interface). This eliminates the need to manage presets. Only after you have robust processing in place should you consider a measurement microphone to visually identify problem areas and observe the impact of your EQ adjustments.