General Overview
• Designer: Erno Borbély
• Output Power: ≈ 60 W RMS into 8 Ω (about 100 W into 4 Ω)
• Topology: Class AB push-pull with complementary MOSFET output stage
• Period: Originally published in the early 1980s (later refinements appeared through the
1990s–2000s)
• Notable for: Extremely linear MOSFET operation, excellent thermal stability, and very low
distortion (< 0.01 %).
Originally featured in Audio Amateur and The Audio Electronics magazines (circa 1983–1994).
• Borbély later refined these in his EB-60, EB-100, and EB-602 kits sold through Borbély Audio
in Norway.
• His “MOSFET Power Amplifiers” article series remains a classic for DIYers and engineers interested
in lateral-MOSFET linear amplification.
Sound Characteristics
Erno Borbély’s MOSFET designs are known for:
• A tube-like smoothness (due to the lateral MOSFETs’ transfer curves).
• Tight, detailed bass and open, transparent midrange.
• High reliability — very hard to destroy thermally or through speaker load mismatch.
Output power: 60Wrms @ 8 Ohms
Frequency response: 8.2Hz - 35KHz (-1dB)
Input sensitivity: 495 mV
