User manual NAD M25

[. . . ] 1 Read instructions - All the safety and operating instructions should be read before the product is operated. 2 Retain instructions - The safety and operating instructions should be retained for future reference. 3 Heed Warnings - All warnings on the product and in the operating instructions should be adhered to. 4 Follow Instructions - All operating and use instructions should be followed. [. . . ] The Soft Clipping LED on the front panel illuminates when the Soft Clipping circuit is engaged. Soft Clipping can be defeated with a rear panel switch. The 12V trigger connection on the back panel allows the amplifier to be switched from On to Stand-by and vice-versa remotely. This way, the M25 can be part of a system which can be turned on and off with a single command, easing operation. The 12V trigger also allows the amplifier to be installed in places not in easy reach. THE DESIGN The NAD M25 houses seven individual amplifiers, each on separate circuit board. Each amplifier channel acts as a "mono block" within the chassis. each input connector , and set of loudspeaker output terminals , is directly connected to that channel's circuit board. This design eliminates extra wiring and keeps signal paths short. furthermore , this modular design increases reliability and thermal efficiency. The input circuit uses a totally new dual differential input topology that operates in true Class-A mode. The special HolmgrenTM toroidal transformer has less hum and magnetic leakage than conventional toroidal transformers, but retains the usual benefits of high efficiency and high power-to-weight ratio. This provides highly effective protection that does not effect audio performance. Each channel is protected against excess temperature, DC fault and loudspeaker short-circuit. The M25's inherently conservative, high-voltage/high-current output stage has been designed for years of trouble-free service. NAD was the first company to introduce a THX® Certified power amplifier. As a result the NAD M25 will handle the most demanding signals with ease, and yet preserve every subtle audio detail in the most demanding THX® Ultra2TM Surround systems. POWERDRIVE To meet the diverse requirements of high current drive and high dynamic power, our patented PowerDrive amplifier circuit will build further on our reputation for amazingly effective power. By adding a second high-voltage rail to our well regulated high-current power supply, we get an "overdrive" that can nearly double the continuous power on a short term dynamic power basis. This is a further development and refinement of our renowned Power Envelope circuit, utilized by NAD in the 80's and 90's. PowerDrive differs from Power Envelope in that it offers greater amplifier stability and low impedance drive capability, resulting in less distortion when driving real speakers with real program material INSTALLATION PRECAUTIONS WARNING - To reduce the risk of fire or electrical shock, do not expose the amplifier to rain or moisture. Do not transport the apparatus using one shipping container; to do so may result in damage to either the apparatus or personnel. [. . . ] Then remove all connections from the amplifier. Only replace the fuse with the same type, size, and specification. In the event of radio hum or radio interference, this terminal can be connected to a `true earth' such as a copper plated rod driven several feet into the ground. The Protection LEDs turn red for about 3 seconds, every time the amplifier is switched on. [. . . ]