Mains Connections

Your 250's or 500's have been factory set to the correct mains voltage for your country (well, that is what we intended to do when we knew where it would be initially shipped). There is NO voltage changeover switch inside! The serial number sticker badge will proclaim the voltage we initially set when the unit first shipped from the factory. Additionally there might be a yellow 120V sticker or a red 230V sticker placed near the IEC power inlet. Check the sticker and the serial number voltage indication for proper mains voltage and confirm that agrees with what comes out of your wall. THIS IS IMPORTANT. Failure to properly comply with mains voltage requirements can cause extensive damage to the system, which of course would not be covered by the warranty. If you relocate from, say, a 120V country to a 240V country, you will need to re-wire the power transformer primaries to agree with new new mains voltage and you will also need replace the mains fuse value with the proper value for the new operating voltage. Or you can ignore all this and use a step-up (or step-down) outboard converting transformer to power the unit from. But he had better be BIG for these huge amps...

ALWAYS DISCONNECT THE IEC MAINS CABLE BEFORE OPENING THE UNIT AND ALWAYS ALLOW 30 MINUTES TO ALLOW THE CAPACITORS TO DISCHARGE FOR SAFETY'S SAKE SO YOU DO NOT HAVE A SHOCKING EXPERIENCE. THOSE EXPERIENCES ARE NOT EVEN A LITTLE FUN.

The mains fuse may be checked by first disconnecting the IEC mains cord from the power supply’s power inlet plug. Then grab the knob cap and gently pull out the fuseholder retainer cover. The fuse and cap should spring outward toward your fingers. Inspect the fuse for the proper rating; change if necessary. The B+ fuse cap cover is to be rotated counter clockwise with a 1/4" flat screwdriver to release it from its housing.

Refer to the fuse rating charts in the specifications section of this manual. If you do not know what a blown fuse looks like, you may measure for continuity across the fuse ends with a multimeter set to read resistance, ohms, or the omega symbol. If your meter reads “OL” when you measure across the fuse, that means “Open Leads” and that would mean the fuse is blown. A blown fuse usually indicates A Very Bad Thing occurred. If this has happened to you, try to figure out why it may have happened. (Using a Fast Blow fuse when we have specified a SLO-BLO fuse is one reason...) If you have no idea why a fuse might have just blown on its own, you might want to consult with Manley Labs or your dealer for further advice as to what Very Bad Thing might have occured, like the power transformer might have decided to retire early or protest its oppressive conditions.

One way this could happen is by running the wrong mains voltage into the unit. Be sure not to do that.

If you live in a strange place...

Export units for certain markets have a moulded mains plug fitted to comply with local requirements. If your unit does not have a plug fitted the coloured wires should be connected to the appropriate plug terminals in accordance with the following code.

GREEN/YELLOW	EARTH terminal
BLUE	NEUTRAL terminal
BROWN	LIVE terminal

As the colours of the wires in the mains lead may not correspond with the coloured marking identifying the terminals in your plug proceed as follows:

The wire which is coloured GREEN/YELLOW must be connected to the terminal in the plug which is marked by the letter E or by the safety earth symbol or coloured GREEN or GREEN and YELLOW.

The BLUE coloured wire must be connected to the terminal in the plug which is marked by the letter N or coloured BLACK.

The BROWN coloured wire must be connected to the terminal in the plug which is marked by the letter L or coloured RED.

DO NOT CONNECT OR SWITCH ON THE MAINS SUPPLY UNTIL ALL OTHER CONNECTIONS HAVE BEEN MADE. (...or else...)

AMPLIFIERS specifications

Manley Labs, a renowned name in high-fidelity audio equipment, has established a reputation for its premium amplifiers, celebrated for their exceptional sound quality and innovative design. With a commitment to craftsmanship and the integration of cutting-edge technology, Manley amplifiers cater to audiophiles and professionals alike, delivering a listening experience that is both immersive and authentic.

One of the hallmark features of Manley amplifiers is their use of high-quality vacuum tubes in many of their models. The warmth and richness that tubes impart to the audio signal are particularly appealing to music lovers who seek a classic analog sound. Models like the Manley Stingray and the Manley 300B offer a distinctive tonal character, allowing musicians and listeners to experience the nuances of recordings as intended by the artists.

In addition to tube technology, Manley amplifiers frequently incorporate advanced solid-state circuitry, striking a balance between traditional warmth and modern reliability. The Manley Reference Amplifier exemplifies this hybrid approach, featuring a robust power supply and precision engineering that ensures a clean, dynamic sound. This versatility allows the amplifiers to perform beautifully in various listening environments, from home setups to professional studio applications.

Manley Labs is also notable for its attention to build quality. The amplifiers are crafted in the USA, utilizing high-grade components and rigorous quality control processes. This commitment to craftsmanship means that every unit is built to last, ensuring long-term reliability and performance. The aesthetic appeal of Manley amplifiers, with their distinctive vintage-inspired designs and premium finishes, further enhances their desirability.

Another key characteristic of Manley amplifiers is their versatility in handling various types of audio signals. Models like the Manley Neo-Classic 300B can accommodate both low-impedance and high-efficiency speakers, making them suitable for a wide range of setups. Additionally, features such as customized input and output transformers help to optimize the performance for different audio sources.

In conclusion, Manley Labs amplifiers embody a blend of vintage charm and contemporary engineering. Their proprietary tube designs, robust solid-state options, and unwavering quality make them a standout choice for anyone seeking an exceptional audio experience. Whether in a casual listening room or a high-end studio, Manley amplifiers promise to deliver richness, clarity, and a connection to the music that transcends the ordinary.