MBL Noble Line N11/N15 Preamp & Monoblock Power Amps Jürgen Reis

Jürgen Reis

MBL's chief engineer and 'public face' of this respected German brand, Jürgen Reis, is cautious about revealing too much about the proprietary working behind his 'LASA 2.0' amplifier technology.


'We have optimised the behaviour of the output stage circuitry to drive real loads', he emphasised during our call over the Xmas break. 'We employ a "four quadrant" test that looks at our amplifier output current and voltage both in- and out-of-phase,

ensuring it will drive the most reactive loudspeaker loads without becoming overstrained. We've also introduced a low-impedance grounding concept for the power supply and output stage, meaning higher transparency and improved control over the frequency range.'

At the heart of the N15 is a proven Ncore NC1200 Class D module from Hypex whose 5th-order self-oscillating control (feedback) loop encompasses the full audio path, including the output filter network. It's this technique that ensures the N15 maintains a predictable frequency response regardless of the speaker load, unlike more traditional Class D

amplifiers. Nevertheless, MBL has nested the NC1200 module within a distinctly 'audiophile' environment, including a huge linear power supply and with proprietary switching transistors at the amplifier's output.

There's some customisation of the Ncore module's parameters, too. 'We have made the amplifier's transition to clipping more gentle', says Jürgen, 'even at very high sound levels or when driving tough speaker loads, the amplifier will not appear aggressive or distorted'. PM

MBL Akustikgeräte GmbH & Co. KG
Berlin, Germany
Supplied by: Stranger High Fidelity, Real World Studios, Wilts
07702 155847