Introduction, Thank YOU | Manley Labs 300B specs

INTRODUCTION

THANK YOU!...

for choosing the Manley Laboratories "The 300B Preamplifier". Designed by David Manley, the 300B Preamplifier uses the best available parts with the shortest, cleanest, signal path possible. This Preamp features the 300B direct heated triode as the line and headphone driver. The 300B is typically used in low power amplifiers as the only power tube. These amps generally deliver 5 to 9 watts single-ended and cost from $3000 to over $100,000 Some of these amps sound very nice coupled with efficient speakers. We build an amplifier that uses a pair of 300B's that can be operated single-ended or push-pull and delivers up to 36 watts. We consider the 300B to be an extremely good tube for low power purposes. Driving headphones and cables is a very good application for these tubes. Here is where the impedances are not too low and the power requirements are not too high, however, these applications are near the limits of where smaller triodes and dual-triodes are usable. We combine the classic 300B with another classic - the 6SL7GT to provide the complete amplification stage. To complement this tube choice we chose to use tube based rectification and regulation as well as our usual extreme filtering.

To complement our best sounding line driver to date, we used the techniques of the best passive preamps. We used a 24 position gold contact Grayhill switch with metal-film 1% 1/2 watt resistors for a superior audio attenuator and a widely separated ceramic switch for input selection. Also used were, gold plated connectors, high purity copper wire, Mil-spec printed circuit boards with extra thick copper and plating, and custom designed transformers.

The elegant front panel finish is a high purity plated gold that complements the electronics both visually and in its long lasting outstanding quality. Please take a few moments to read through this manual, there may be features and information about this preamplifier which you should familiarise yourself with.

Thank you again, and please enjoy!

GENERAL NOTES

LOCATION & VENTILATION

The Purist Preamplifier must be installed in a stable location with ample ventilation. It is recommended, if this unit is rack mounted, that you allow enough clearance on the top and bottom of the preamp such that a constant flow of air can flow through the ventilation slots. We also recommend that the preamplifier be placed at least 10 inches away from its amplifier.

WATER & MOISTURE

As with any electrical equipment, this preamplifier should not be used near water or moisture.

SERVICING

The user should not attempt to service the preamplifier beyond that described in the owner's manual. Refer all servicing other than tube replacement to Manley Laboratories.

SPECIAL NOTES

The 300B's are packaged separatly to prevent damage. You will need to carefully plug them in before powering the preamp. Pay attention to the size of the pins to properly align the tubes before inserting. The large pins go into the large sockets. It is difficult but possible to insert the 300B's wrong and damage the preamp. Tubes may become loose during transit. Straighten and press down each tube before plugging the preamplifier into the mains socket. Furthermore, do not touch the tubes after the preamplifier has been switched on, as the tubes do become very hot during operation and should only be handled after the power has been turned off and the tubes have cooled.

300B specifications

Manley Labs 300B is a high-fidelity tube amplifier that has gained a reputation among audiophiles for its exceptional sound quality and craftsmanship. This amplifier is named after its use of the 300B vacuum tube, a component famous for producing a warm, rich sound that is both detailed and engaging. The Manley Labs 300B amplifier has become a reference point for those who appreciate the artistic qualities of sound reproduction.

One of the key features of the Manley Labs 300B is its fully balanced design, which helps to minimize noise and distortion. This design approach allows for greater dynamic range and clarity in the audio signal. The use of premium components throughout the circuit further enhances performance, ensuring that every note is rendered accurately and with depth.

In terms of power, the Manley Labs 300B delivers 8 watts per channel in a class A operation, which is a hallmark of high-end audio equipment. While this may seem modest by modern standards, the quality of sound produced is often more important than sheer wattage. The 300B’s output stage offers a creamy and dynamic sound, excelling particularly with vocal and instrumental music, where it conveys subtle details with remarkable fidelity.

Another significant aspect of this amplifier is its flexibility in terms of speaker compatibility. It is designed to drive a variety of speakers, making it a versatile choice for different listening environments. The Manley 300B supports both 4 and 8-ohm output impedance settings, allowing users to match it to their favorite loudspeakers for optimal performance.

Additionally, the amplifier's construction is noteworthy. It features a robust chassis that not only reduces resonance but also adds to the overall durability of the unit. The hand-built nature of the Manley Labs 300B ensures that each piece is crafted with meticulous attention to detail and quality.

The Manley Labs 300B also comes equipped with a rich array of features, including an input selector, volume control, and high-quality binding posts for speaker connections. These components are not just functional; they also reflect Manley’s commitment to providing a user-friendly and high-performance experience.

In summary, the Manley Labs 300B is a sophisticated and beautifully crafted tube amplifier that offers a level of sonic performance that is hard to match. Its combination of high-quality components, thoughtful design, and powerful performance make it a standout choice for audiophiles seeking a true musical experience. Whether used in a dedicated listening room or as part of a larger audio setup, the Manley Labs 300B delivers a sound that is both engaging and lifelike.