The  WiiM Amp Ultra is powered by the high-performance ESS ES9039Q2M DAC, delivering exceptional audio clarity and ultra-low distortion.


To further fine-tune the Speaker Out audio output, the DAC provides eight digital filter types. Each filter slightly changes how high-frequency content is processed, allowing you to adjust the sound character based on your listening preference.

Eight DAC Digital Filter Types


1. Minimum Phase
Default Recommended
Key Feature: Minimum phase filtering with balanced timing and detailed presentation.
Benefit: Delivers natural timing with clear detail and overall balanced sound.
Suitable Audience: Listeners seeking a natural and well-balanced everyday listening experience.
2. Linear Phase Fast Roll-Off Apodizing
Key Feature: Linear phase fast roll-off with digital artifact reduction.
Benefit: Smooths harsh recordings and older CDs by reducing digital artifacts.
Suitable Audience: Users listening to early digital recordings or sensitive to harsh treble.
3. Linear Phase Fast Roll-Off
Key Feature: Linear phase filtering with fast roll-off and flat response.
Benefit: Provides maximum accuracy and neutral frequency response.
Suitable Audience: Reference listeners and users prioritizing technical precision.
4. Linear Phase Fast Roll-Off Low Ripple
Key Feature: Linear phase fast roll-off with minimized ripple.
Benefit: Ensures pure tonal accuracy with minimal coloration.
Suitable Audience: Studio monitor users and listeners seeking tonal neutrality.
5. Linear Phase Slow Roll-Off
Key Feature: Linear phase filtering with gradual high-frequency roll-off.
Benefit: Produces relaxed, smooth treble suitable for long listening sessions.
Suitable Audience: Users who prefer softer highs and fatigue-free listening.
6. Minimum Phase Fast Roll-Off
Key Feature: Minimum phase fast roll-off emphasizing transient clarity.
Benefit: Delivers punchy, dynamic sound with clear transients.
Suitable Audience: Listeners who enjoy bass impact and energetic live music.
7. Minimum Phase Slow Roll-Off
Key Feature: Minimum phase filtering with reduced digital filtering intensity.
Benefit: Creates a warm, natural, and analog-like presentation.
Suitable Audience: Users who prefer smooth, musical, and less processed sound.
8. Minimum Phase Fast Roll-Off Low Dispersion Recommended
Key Feature: Minimum phase fast roll-off optimized for clarity and timing balance.
Benefit: Offers the best balance of clarity, smoothness, and timing.
Suitable Audience: Most users looking for an all-around balanced sound profile.

DAC Digital Filter Settings


  1. Open the WiiM Home app.
  2. Go to the Devices tab > Device Settings > Audio Output.
  3. Select Speaker Out as the audio output, then tap on DAC Digital Filter Type.
  4. Select the filter that best matches your listening preference.