Klein & Hummel O300 – Professional 3‑Way Studio Monitors (Used, Fully Working)

Selling my trusted Klein & Hummel O300 monitors — a legendary 3‑way active system known for accuracy, depth, and effortless translation. These are used but in full working order, with cosmetic scratches on the sides. The marks are visible in the photos, and I’ve included a video link where they can be seen more clearly. Sonically, they perform exactly as they should. Note on the video edges of monitor look a little weird, this is just because I used a background remover, they do not have wobbly edges. The sale includes the original double walled boxes, which they will be shipped in and the original manuals and European power leads.

⭐ Why These Monitors Are Special

  • True 3‑way design with dedicated drivers for lows, mids, and highs
  • Exceptionally flat, neutral frequency response — ideal for mixing and mastering
  • Renowned imaging and stereo depth, still competitive with modern high‑end monitors
  • Built to a broadcast‑grade standard with extremely low distortion
  • A favourite in professional studios long before Neumann acquired K&H

🔧 Technical Specifications

  • Drivers:
    • 8” woofer
    • 3” soft‑dome midrange
    • 1” titanium tweeter
  • Amplification:
    • 150 W (bass)
    • 70 W (mid)
    • 70 W (treble)
  • Frequency Response: approx. 34 Hz – 20 kHz
  • Max SPL: around 112 dB
  • Inputs: XLR
  • Design: Sealed cabinet for tight, accurate low‑end
  • Dimensions: 330 × 253 × 300 mm
  • Weight: 13.5 kg each

🔄 Comparison to Neumann KH310

The O300 is the predecessor to the Neumann KH310, and they share the same design philosophy. Both are 3‑way sealed monitors with a focus on precision and neutrality. Key differences:

  • Midrange driver:
    • O300 uses a 3” soft‑dome mid, known for its smoothness
    • KH310 uses a 4” composite mid, offering slightly more output and detail
  • Amplification:
    • KH310 amps are more modern and efficient
  • Voicing:
    • O300 is often described as a touch warmer and more natural
    • KH310 is a bit cleaner and more analytical

In practice, the O300 still holds its own against the KH310 and is preferred by many engineers for its musical midrange and classic K&H character.

This item is sold As-Described

This item is sold As-Described and cannot be returned unless it arrives in a condition different from how it was described or photographed. Items must be returned in original, as-shipped condition with all original packaging.Learn More.

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Listeda month ago
ConditionGood (Used)
Good condition items function properly but may exhibit some wear and tear.Learn more
Brand
Model
  • 0300
Finish
  • Black / Grey
Categories
Year
  • 2000's
Made In
  • Germany

Product safety information may be available here.

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Dublin, Ireland
Joined Reverb:2025

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