Bang & Olufsen Penta Mk2 (1978)
The Bang & Olufsen Penta Mk2 came out in 1978. It belongs to B&O's Penta series, and the Mk2 refined the original with better acoustic performance and build quality. The design is minimalist Scandinavian, and the construction is modular.
Specifications
| Feature | Specification |
| Year of Production | 1978–1982 |
| Power Handling | 60W RMS per channel |
| Impedance | 4 ohms |
| Sensitivity | 86 dB |
| Frequency Response | 45 Hz – 20 kHz (approximate) |
| Tweeter | 1" dome with Acoustic Lens technology |
| Woofer | 2 x 6.5" woofers (one per column) |
| Crossover | Adjustable passive network, 2.5 kHz nominal |
| Enclosure | Modular columns, beech wood construction |
| Placement | Wall-mountable or stand-mounted |
| Dimensions (H×W×D) | 95 cm × 22 cm × 22 cm per column |
| Weight | 12 kg per column |
Design and Key Features
The Penta Mk2 is a modular design built as two separate vertical columns - one holds the woofer and the other the tweeter. The split was meant to improve stereo imaging and reduce inter-driver interference. Each column is made from solid beech wood, which adds visual warmth and acoustic damping.
The Acoustic Lens tweeter is the standout B&O feature here. It spreads high frequencies evenly across a wide listening area, which reduces the "sweet spot" limitation common in conventional tweeters. The lens gives a smooth off-axis response and consistent clarity throughout the room.
An adjustable crossover network lets you tune the tonal balance. That helps when adapting the speakers to different room acoustics or personal preferences. The system is also wall-mountable, which fit B&O's design philosophy of working into modern living spaces.
Sound Signature
The Penta Mk2 has a neutral and precise sound profile. Highs are clear and detailed, thanks to the Acoustic Lens. The midrange is well balanced, so vocals and acoustic instruments sound natural and present. Bass is tight and controlled, but modest because of the sealed enclosure and the 45 Hz lower limit. Smaller to medium-sized rooms suit it best.
Imaging is excellent, with a wide and stable soundstage. That comes from the vertical driver separation and the time-aligned crossover. It isn't bass-heavy, but it is accurate and tonally coherent, which suits jazz, classical, and vocal-centric music.
Historical Significance
The Penta Mk2 came out during a period of bold experimentation at Bang & Olufsen. As part of the Penta series, it pioneered the modular speaker concept and challenged traditional cabinet designs. The look is minimalist - no grilles, clean lines, natural wood - and reflected the Danish modernist movement. It set a precedent for later B&O products.
The speaker became a symbol of luxury hi-fi in the late 1970s and early 1980s. It showed up often in architect-designed homes and high-end audio showrooms.
Maintenance and Restoration Tips
Because of their age, Penta Mk2 speakers often need maintenance to restore optimal performance:
- Foam Surround Replacement: The original foam surrounds on the woofers are prone to disintegration after 40+ years. Re-coning or replacing with modern rubber surrounds is highly recommended.
- Crossover Capacitors: Electrolytic capacitors in the crossover network degrade over time, leading to muffled sound or imbalance. Replacing these with modern film capacitors improves clarity and reliability.
- Wiring and Connectors: Check for corrosion on binding posts and internal wiring. Clean or replace as needed to ensure solid electrical contact.
- Wood Finish Care: Clean beech wood columns with a soft, dry cloth. Avoid harsh chemicals; use wood conditioner sparingly to restore luster.
- Mounting Hardware: If wall-mounting, ensure brackets are secure and compatible with modern standards.
Restored pairs in original condition are highly sought after and can command premium prices in the vintage audio market.
Collectibility and Market Value
The Bang & Olufsen Penta Mk2 has a collectibility rating of 7/10. Audiophiles and design collectors both want it, thanks to its design, its historical relevance, and its link to B&O's golden era.
As of 2024, a pair of Penta Mk2 speakers typically sells for $300-$600, depending on condition, originality, and restoration quality. Fully restored units with upgraded components and preserved wood finishes tend to reach the higher end of the range. Original packaging or accessories can add to the value.
Conclusion
The Bang & Olufsen Penta Mk2 remains a testament to the fusion of form and function in high-end audio. More than just speakers, they are design artifacts from a pivotal moment in audio history. With proper care and restoration, the Penta Mk2 continues to deliver a listening experience that is as emotionally engaging as it is technically refined—proving that great design is truly timeless.
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