Description
Based on our experience, we have created an amplifier whose sound will satisfy even the most demanding listener. If to summarize the sound of this unit, it would be characterized by words such as ‘scale’, ‘fullness’, and ’layering’. No detail has been overlooked in the development of this model.
Mono Input and Sync Module
For the most demanding listeners, we have developed a scheme to synchronize the two amplifier units. This allows for an even greater power reserve, resulting in a previously unattainable listening experience.
Each channel of the amplifier operates in a fully balanced mode. You simply select which unit is the primary and which is the secondary.
This will synchronize the volume levels of the two units. The synchronization system also allows you to control the operation of the second amplifier, so that when the primary unit is switched on, the second unit is automatically switched on.
Power Supply
The amplifier is built on the dual mono principle, with each channel having its own power supply and power transformer. This provides a wide soundstage and dynamic range. The power supply for each channel uses four high-capacity capacitors manufactured by Cornell Dubilier Electronics, capable of delivering significant current at their output and having a low output impedance. This is the basis for dynamic and detailed sound.
The power supply utilizes custom power transformers with a very low dissipation field and noise. This permits the amplifier circuit to function without any apparent hum, even when using high-sensitivity headphones.
We have also used an Ultra Pure Oxygen Free Copper (UP-OFC) power cable with additional shielding from Neotech from the AC Inlet socket to the power transformers. This has allowed us to achieve a more focused sound in the low-frequency range and more punch in the mid/high range. You will get the most out of this unit if you use a good-quality power cable, but you can be sure that you already have a great basis!
Amplifier Part
The output stage operates in class A, which allows transmitting signals of small amplitude with the highest accuracy. The amplifier circuitry uses J-Fet transistors at the input for a meaty and smooth sound, and bipolar transistors at the output, specially designed for use in high-end audio circuits, to deliver the highest fidelity and transparency. The power supply for the amplifier circuitry is 70 volts to ensure uncompromising dynamic performance with the most demanding headphones on the market.
By refining the heat sink design, the amplifier circuitry is promptly prepared for utilization, and subsequently shares in its greatest sound quality only after a mere 15 minutes. In addition, we have partially placed the heat sink under some of the PCB components, which allows the amplifier circuitry to start up faster and provides better thermal stability for the entire circuitry.
We use Ohno monocrystalline copper (UP-OCC) cable at the output. This allows the amplifier’s circuitry to unfold to its full potential – the mid-range comes into full color and no detail is hidden from the listener’s ears.
To achieve a balanced and refined sound, the amplifier has been carefully selected from a wide range of components. Components used in the circuits include Takman resistors (Rex and Rey series), extremely expensive Vishay VAR series uncased audio resistors, PRP resistors, Cornell Dubilier, Nichicon, Wima, and Epcos capacitors.
Volume control
The volume control is based on a relay attenuator and contains 64 steps. The control circuit uses Panasonic fast signal relays with low contact resistance. The analog signal is fed to the relay attenuator located next to the input sockets, and the ALPS variable potentiometer (Blue Velvet series) is used for control only.
This arrangement allows the classic potentiometer to be used for volume control, with the analog signal going to a relay control located next to the input jacks. This allows for high sonic transparency even at low volumes.
In this amplifier model, we have enhanced the volume control program for better system response and improved overall usability. This volume control eliminates the problem of volume imbalance between channels and enables you to finely tune the level even on high-sensitive headphones.
Aluminum RC
Optionally we offer a volume remote control with a laconic and austere design. The unit is CNC-machined from top-quality aluminum to guarantee its strength and durability.
The remote is coated in a black anodized finish, imparting a stylish appearance while shielding it from abrasions. The buttons have a distinct, effortless movement and are tactually distinguishable. Our accessory guarantees reliability and functionality, making it a delightful supplement to your amplifier.
Neotech UP-OFC Power Cable
In the discerning world of high-fidelity audio, every component, including often-overlooked power cables, plays a crucial role in shaping the overall sound quality. Drawing upon extensive experience in crafting high-end audio systems, we’ve selected a meticulously optimized solution at an exceptionally reasonable value. We want to share high-quality power cable which enhances audio quality by expanding dynamic range, with improved resolution, and offers a noticeable and rewarding addition to your desktop system.
Our power cable based on an NEP-5002 conductor from Neotech, delivers outstanding value for money. Its construction features thick conductors (0.42mm) of ultra-pure oxygen-free copper (UP-OFC), ensuring exceptional dynamics and resolution. The ground conductor’s smaller cross-section (1.43mm2) results in a slim and flexible cable for a better user experience.
The cable provides complete protection from external electromagnetic radiation, thanks to an internal aluminum foil shield and a drain wire. Filling the free volume with synthetic fiber ensures comfortable flexibility and a “memory” effect, allowing the cable to be easily positioned and maintained in the desired position.
Each cable is hand-crafted in our workshop and equipped with high-quality TAFF or VIBORG connectors with gold-plated copper contact groups. The cable is supplied in a length of 1.8 meters (6 feet). We are striving to enhance your audio experience and unlock the true potential of your sound system.
Neotech UP-OCC Headphones AdapterÂ
For a fully balanced connection between headphones and two devices using a conventional balanced XLR 4-pin cable, we offer a high-quality DUAL 3-pin male to 4-pin XLR female adapter cable.
It is designed with four separate wires, each made up of Neotech UP-OCC multi-strand cable produced from Ohno cryo-treated monocrystalline copper. The wire gauge is 22 AWG (one wire comprises 115 cores with an overall cross-section of 0.33 mm2). Each cable is meticulously crafted in our workshop and fitted with connectors supplied by Neutrik, a world-renowned leader in high-quality connectors with a reputation for exceptional reliability. The cable comes in a length of 1.1 meters (3.6 feet).
paul99kg (verified owner) –
FA-10 was already one of the best headphone amplifiers I have for any planers such as Abyss 1266, Audeze LCD etc over the years. The Mentor Fully Balanced Stack is just out of this world! Image clarity and separation, bass slam, sound coherency was eyes-opening good! I am using Smyth Research Realiser for an immersive headphone listening setup that can mimic the exact listening experience of my big rig of tri-amped Full size Ribbon loudspeakers and horns with REL subs etc in my listening room. With the Mentor Fully Balanced Stack, the headphone setup now will sounded even better than my big rig!, Sound over the Mentor is more realistic and majestic and yet detailed and neutral and fast I cannot imagine any equipment can bring this to happen. Thank you Flux Lab for making the Mentor Stack!!!
michaelidesx (verified owner) –
I was looking at various headphone amplifiers that could drive my Hifiman Susvara and the Volot amplifier by Flux Lab Acoustics was a match made in heaven for my Susvara but unfortunately Volot was discontinued. That’s when I found out about the Mentor amplifier from Flux Lab Acoustics and I was especially interested in the Mentor stack because it could deliver 33.5 watts per channel in 32 Ω and 6.4 watts per channel in 300 Ω which are insane numbers for a headphone amplifier!
The Mentor stack delivers a highly technical and resolving sound that is very neutral and the voice and notes are full of life and emotion and very engaging, I feel like I am sitting in the front row of a very wide musical hall and a live performance is unfolding in front of me. The Mentor stack can tackle anything you throw at it and it will excel while doing it. I feel like it does everything at the correct amount without feeling that something is off. I would give the Mentor stack extremely high marks in every category and also the amplifiers don’t even get hot, just barely warm after hours and hours of continuous listening. I feel like the Mentor stack is the perfect amplifier if you want to drive power hungry headphones and not break the bank and also without dipping your toes in the potentially dangerous territory of speaker amplifiers.
Flux Lab Acoustics have a winner in their hands (AGAIN!) and I am happy and proud to support their incredible products and amazing customer service. Thank you for this wonderful product!