Hi everyone,
A person in a hurry to test two amps (a Nad 3120 and an Audiophonics MOS120) connected to the same pair of speakers to these amps.
The MOSFET Audiophonics is alive, but the Nad didn't make it. Sound is now super distorted.
Two of the four fuses are dead. When I replace the 1A that is dead, it immediately flash and dies after powering on the amp.
What's your take on this ?
All the best
A person in a hurry to test two amps (a Nad 3120 and an Audiophonics MOS120) connected to the same pair of speakers to these amps.
The MOSFET Audiophonics is alive, but the Nad didn't make it. Sound is now super distorted.
Two of the four fuses are dead. When I replace the 1A that is dead, it immediately flash and dies after powering on the amp.
What's your take on this ?
All the best
Last edited:
NAD3120
The 3120 has two independent supplies. A regulated +33.0/-24.2 supply that is fused with 1A fuses and a high power +33.3/-33.3 unregulated supply that is fused with 4A fuses. The regulated supply is used throughout the preamp and the power amp and the high power section is used for the discreet darlington output transistor circuit.
Because the fuse opens so violently, I would expect a short circuit somewhere in the amplifier or in the regulator circuit. It is important to determine the exact fuses that are blowing in order to narrow it down. Short circuits can be challenging to find sometimes because you can not troubleshoot the circuit under live conditions.
Bob
The 3120 has two independent supplies. A regulated +33.0/-24.2 supply that is fused with 1A fuses and a high power +33.3/-33.3 unregulated supply that is fused with 4A fuses. The regulated supply is used throughout the preamp and the power amp and the high power section is used for the discreet darlington output transistor circuit.
Because the fuse opens so violently, I would expect a short circuit somewhere in the amplifier or in the regulator circuit. It is important to determine the exact fuses that are blowing in order to narrow it down. Short circuits can be challenging to find sometimes because you can not troubleshoot the circuit under live conditions.
Bob
"connected to the same pair of speakers to these amps."
Not at the same time --I hope ?
The two 1amp fuses connect to the power supply transformer AC output
I would first check the Full-wave rectifier for a faulty diode .
Next check out both pass transistors in the power supply for short circuit ,if they are faulty it could be a fault in your output transistors .
Thats just an initial check before you become more involved.
Not at the same time --I hope ?
The two 1amp fuses connect to the power supply transformer AC output
I would first check the Full-wave rectifier for a faulty diode .
Next check out both pass transistors in the power supply for short circuit ,if they are faulty it could be a fault in your output transistors .
Thats just an initial check before you become more involved.
