Cleaning: To ensure the best sound quality and the longest product life, we recommend cleaning your ASTRU in-ear monitor ear tips regularly. To ensure the best sound quality and the longest product life, we recommend cleaning your ASTRU in-ear monitor ear tips regularly.

Recommended Burn-In Time (If Performed)
Duration: 30–50 hours to allow the PU to settle fully.

For maximum refinement, up to 80 hours is optional.

What to Play:
Pink noise, low-frequency test tones, or full-spectrum sweeps help the driver reach optimal performance faster.

Regular music also works, just more slowly.

Listening Volume:
Keep the volume at a moderate level (~ 75dB) during burn-in.

Low-end test tones should not be played at high volume during the first 10–15 hours.

Burn-in Cycles:
For best results, use 4–6 hours of playback, followed by a 1- hour rest period.

What Improves After Burn-In (Sound Benefits):

Deeper, Cleaner Bass:
As the PU surround softens naturally, the driver gains more low-end extension and tighter, more controlled sub-bass.

Smoother, More Open Mids:
Midrange becomes cleaner and more coherent as the mechanical suspension stabilizes.

Refined Transients & Natural Detail:
The diaphragm features a PEEK dome, layered with 80 ultra-thin gold coatings applied over a 48-hour sputtering process, topped with a titanium outer layer.

This advanced structure already delivers superb clarity and fast transients, which feel even more natural once the surround settles.

Lower Distortion:
Burn-in helps reduce low-frequency distortion, resulting in a cleaner, more accurate presentation.

Stable High-Frequency Performance:
The multi-stage PEEK–Gold–Titanium dome is extremely stable from first use, maintaining crystal-clear treble throughout the burn-in period.

If you have connected the Boom Mic to your PC and the recorded audio is on the quieter side, it is possible that your PC's motherboard does not have sufficient power to drive the Boom Mic to its optimal capacity. In this case, we recommend using an external DAC/AMP with dual 3.5 mm connections (headphone input and microphone output), and using the provided Y-adapter to create your signal chain. Employing the use of a 3.5 mm female to USB-C male adapter is also a suitable solution.

Troubleshooting: If you are not getting signal on the Left or Right channel, try switching the Left cable to the Right ear cup and vice versa to identify whether the Boom Mic is defective or the headphones are.

Cleaning: To ensure the best sound quality and the longest product life, we recommend cleaning your ALBA in-ear monitor ear tips regularly.To ensure the best sound quality and the longest product life, we recommend cleaning your ALBA in-ear monitor ear tips regularly.

Burn-In Parameters (If Performed)
Duration: 10–30 hours is sufficient for minor compliance settling

Signal Material: Pink noise or full-range music at moderate levels. LF-weighted noise is optional; the effect is minimal

Volume: ~70 dB SPL equivalent; avoid extreme SPL

Rest cycles: optional; not required due to high LCP stability

Expected Acoustic Improvements
Bass: slightly more extended/controlled if the surround relaxes

Mids/Highs: essentially unchanged; LCP provides stable HF and transient response from hour 0

Overall: subtle refinement in naturalness, not tonal shift

In order to extend your 99 Classics headphones' life for as long as possible, we recommend storing them in a dry environment.

In order to avoid potential cosmetic defects, we recommend handling the Empyrean II and Elite headphones with care so as not to exercise excessive pressure on the aluminium grille.

When attempting to detach the 3.5 mm (1/8 inch) cable jacks from your headphones, it is best to grab them by the shell and gently pull them out out one by one, in order to avoid damaging your headphones or your cable.

When attempting to detach the mini-XLR cable inputs from your headphones, it is best to remember that they have a lock-in mechanism in place. Only by firmly pressing the button present on the shell, followed by pulling, can the cable be detached from the headphones.