Uploaded January 2026 | Updated September 2026, 2 weeks ago
tests the ZK TB21 amplifier board with a focus on bass and treble performance. Hear how the tone controls affect sound output and clarity. A simple but detailed test of bass, mids, and highs.
tests the ZK TB21 amplifier board with a focus on bass and treble performance. Hear how the tone controls affect sound output and clarity. A simple but detailed test of bass, mids, and highs.
![Harman Kardon Onyx Studio 9 speaker sound/bass excursion test [no grill]](https://i.ytimg.com/vi/mbuTh_yBIlI/mqdefault.jpg "Harman Kardon Onyx Studio 9 speaker sound/bass excursion test [no grill]
How to remove the speaker grill on the Harman Kardon Onyx Studio 9 portable bluetooth speaker + bass excursion and sound test to see how loud and powerful this portable Bluetooth speaker really is testing dB SPL test. The Onyx Studio 9 is known for its premium design and rich sound, but today we focus on what’s happening behind the grill. I demonstrate how the grill is held in place using plastic clips (similar to Hi-Fi speaker fabric covers) and explain how to remove it carefully without damaging the housing. Once the grill is off, we take a closer look at the woofer, passive radiator, and three tweeters, then move on to a real sound & bass excursion test to check speaker movement, low-frequency performance, and overall loudness. Note: Removing the grill may cause minor scratches if done carelessly. I recommend using tape or plastic tools to protect the speaker finish.
USB C type cable on Aliexpress:
- https://s.click.aliexpress.com/e/_c30UdpKH
Karman Kardon Speakers on Amazon:
- Global https://amzn.to/4p8PvZD
- UK https://amzn.to/4qnPgLy
- DE https://amzn.to/49i2L9L
USB C type cable on Amazon:
- Global https://amzn.to/4qmWak5
- UK https://amzn.to/45eg74j
- DE https://amzn.to/49m7GGE
affiliate links
Harman Kardon Onyx Studio 9 Key Features & Specs:
- Portable Bluetooth speaker
- Premium Harman Kardon sound tuning
- Powerful woofer with passive radiator for deep bass
- 3 tweeters for wider sound coverage
- Wireless Bluetooth audio streaming
- Built-in rechargeable battery
- Stylish fabric and aluminum design
Harman Kardon Onyx Studio 9 Specifications:
- Rated Output Power: 50 W RMS
- Power Supply: 100–240 V AC, 50/60 Hz
- Speakers: Woofer: 1 × 120 mm and Tweeters: 3 × 20 mm
- Frequency Response: 50 Hz – 20 kHz (-6 dB)
- Signal to Noise Ratio: more than 80 dB
- Product Dimensions (W × H × D): 289.2 × 287.5 × 130 mm (11.39 × 11.32 × 5.12)
- Gross Weight: 3.33 kg (7.34 lbs)
- Bluetooth Version: 5.3 (A2DP 1.4, AVRCP 1.6)
- USB Port: Type-C (5 V / 2.1 A (Max))
- Battery Type: Li-ion 17.14 Wh (3.63 V / 4722 mAh)
- Charging Time: Approx. 4 hours
- Music Play Time: Up to 8 hours (depending on volume and content)
- Cable Length: 2.0 m (6.6 ft)
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This video is titled in different languages for our international audience:
- latviski: Kā noņemt Harman Kardon Onyx Studio 9 skaļruņa resti + basa ekskursijas tests
- auf Deutsch: Harman Kardon Onyx Studio 9 Lautsprechergitter entfernen + Bass-Excursion-Test
- en español: Cómo quitar la rejilla del altavoz Harman Kardon Onyx Studio 9 + prueba de excursión de bajos
- на русском языке: Как снять решётку динамика Harman Kardon Onyx Studio 9 + тест хода баса
- en français: Comment retirer la grille du haut-parleur Harman Kardon Onyx Studio 9 + test d’excursion des basses
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Test Track: Uplink & Castion - Euphoria [NCS Release]
Music provided by NoCopyrightSounds.
Watch more NCS on YouTube: https://NCS.lnk.to/YouTubeAT
Free Download / Stream: https://ncs.io/Euphoria
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