UOTANG MK9000 Audiophile-Grade 300B Vacuum Tube Amplifier Pure Class A Push-Pull Hi-Fi Tube Amp

Description:
UOTANG MK9000 adheres to the traditional essence of tube amplifiers while integrating UOTANG's innovative modern circuit design philosophy. It represents a powerful combination, delivering a modern interpretation of intricate traditional circuits.

UOTANG MK9000 is a high-power vacuum tube amplifier adopting pure Class A and push-pull topology, which breaks the efficiency limitations of conventional 300B tube amplifiers. It employs rare genuine 300B tubes as output power tubes, operating under a true pure Class A push-pull configuration with 300B tubes serving as transistors. This is the core highlight of the MK9000 and a distinctive feature that sets it apart from similar competing products.

The MK9000 retains the tonal warmth of single-ended 300B output while boasting the high efficiency of push-pull architecture, delivering outstanding performance superior to standard benchmarks in dynamics, damping factor and resolution. While inheriting the core merits of classic tube amplifiers, the MK9000 incorporates UOTANG's cutting-edge modern circuit design. Centered on pure Class A push-pull framework, direct-coupled long-tailed phase inverter and zero negative feedback design, it is equipped with RCA 6GH8A, 17BE3 and UOTANG custom 300B vacuum tubes. It restores the mellow timbre of direct-heated cathode 300B tubes. The push-pull circuit ensures symmetrical driving and balanced phase response, and the zero negative feedback topology preserves rich harmonic overtones. The MK9000 tube amplifier lets you perceive the vivid vitality and warm texture of sound.

The MK9000 delivers remarkable design and performance across all core technical aspects. It features direct-coupled long-tailed phase inverter design, zero negative feedback circuit, triple purification via CLC filter, full-range interface compatibility, pure power amplifier mode, freely switchable dual NFB modes, dual independent wide-frequency output transformers, cathode follower circuit, full-wave tube rectification, tempered glass front panel and full automotive-grade baking varnish body finish.

Features:
UOTANG MK9000 Pure Class A Push-Pull 300B Large Tube Amplifier
* Floor-standing and Bookshelf Speakers Driven Effortlessly
* Pure Class A Tube Amplifier
* 300B x 4 Push-Pull Output
* Direct-Coupled Long-Tailed Phase Inverter Design
* Zero Negative Feedback Design
* Full-Wave Tube Rectification
* Triple Purification with CLC Filter Circuit
* 11 Brand Vacuum Tubes Installed
* High-Power EI-Type Transformer Power Supply
* Dual NFB Mode Switching
* Large Screen Dual Meters
* Can Be Used As Pure Power Amplifier
* Comprehensive Interface Configuration
* Hand-Wound Chassis Plus PCB Circuit Board
* Tempered Glass Panel with Baking Varnish Finish

Combines Distinctive Timbre Characteristics with High Efficiency
* Pure Class A Tube Amplifier
* Direct-Coupled Long-Tailed Phase Inverter Design
* 300B × 4 Push-Pull Output
* Zero Negative Feedback Design

Pure Class A Push-Pull Vacuum Tube Amplifier
* We developed the MK9000 with extremely high technical barriers, a tube amplifier with nearly no equivalent counterparts. It breaks the existing technical bottlenecks for audiophiles who favor authentic tube sound, daring to adopt 300B tubes for pure Class A push-pull operation.
* The MK9000 is a genuine pure Class A push-pull tube amplifier utilizing 300B tubes as output power valves.

Genuine High-Power Push-Pull Output with Four 300B Tubes
* It subverts the mainstream market norm where 300B tubes only act as driver stages and indirectly compromise sound quality. The MK9000 fully unlocks the linear amplification performance of direct-heated triodes, fundamentally refusing to compromise or distort the original acoustic properties of 300B tubes. The core output section of the MK9000 adopts UOTANG-branded 300B vacuum tubes to form a pure Class A push-pull output circuit. The push-pull structure counteracts even-order harmonic distortion while retaining the unique second-order harmonic overtones exclusive to UOTANG MK9000's 300B tubes. Its linear performance, even-order harmonic characteristics and rich mid-range saturation are fully delivered in the final audio output. Especially within this highly technically demanding Class A push-pull design, its warm, delicate classic tube timbre is maximized.

Silent Guardian of High Fidelity: Direct-Coupled Long-Tailed Phase Inverter Design
* The MK9000 adopts the direct-coupled long-tailed phase inverter circuit as the phase controller of its push-pull architecture, converting single-ended input signals into symmetric and balanced positive and negative half-cycle drive signals. Adopting the optimal combination of DC coupling and long-tailed bias configuration, it builds an accurate and solid signal foundation for the 300B push-pull output of the MK9000. The direct-coupled long-tailed phase inverter design of the MK9000 achieves perfect synergy with its pure Class A push-pull architecture. The MK9000 not only resolves the inherent flaws of traditional 300B phase inverter circuits, but also fully unlocks the musicality of 300B tubes, embodying both sophisticated technology and relentless pursuit of premium sound.

Zero Negative Feedback Design
* The UOTANG MK9000 features full-band zero negative feedback design. There is no feedback loop routed back from the output stage within the signal path from the input stage to the power stage. This design fully preserves the noble and authentic timbre of the MK9000's 300B vacuum tubes.
* Fully retain the genuine warm timbre of authentic 300B tubes, delicate instrument decay harmonics, and vocal breath details.
* Conventional negative feedback circuits compress dynamic fluctuations of sound, while zero negative feedback imposes no such restriction and delivers an expansive dynamic range.
* Zero negative feedback demands far stricter component quality standards. Paired with a large power transformer and multi-stage filtering, it achieves an ultra-quiet noise floor.
* The streamlined zero negative feedback circuit eliminates blocking capacitors and adopts direct coupling, delivering an extended frequency response range.

Direct Coupling Circuit Design with High-Fidelity Pre-processing for Pure Signals
* The input stage of the MK9000 utilizes the triode section of vintage American RCA 6GH8A tubes. Equipped with a common-cathode amplifier circuit, the direct-coupled design removes coupling capacitors and introduces signals directly. It maintains the continuity of DC bias configuration, freeing the low-frequency response of the MK9000 from capacitor limitations. This endows the MK9000 with outstanding ultra-low frequency extension capability.

Cathode Follower Circuit Design Preserves Transient Signal Details
* Integrated cathode follower circuitry ensures stable signal transmission across the multi-stage amplification system. The MK9000 leverages the triode segment of the 6GH8A tube to construct the cathode follower circuit. It buffers the impedance mismatch between the high-impedance preamplifier stage and the rear load, enabling clean signal transmission for the MK9000. It safeguards subtle transient details and dynamic information within audio signals.

Dual Hybrid Full-Wave Rectification: Superimposed Secondary Tube Timbre
* The UOTANG MK9000 adopts high-voltage transistor full-wave rectification followed by secondary rectification via 17BE3 vacuum tubes. This design preserves dynamic response while enriching tonal charm and lowering ripple fundamental noise at the source. Its dynamic response aligns closely with the current characteristics of 300B tubes, maintaining the operating point of 300B tubes within the linear amplification region for more natural vocal density and instrumental texture. Meanwhile, the second harmonics naturally generated during the MK9000 rectification process overlap with the even-order harmonics of 300B tubes, adding authentic analog warmth reminiscent of the vinyl era tube sound.

Triple Signal Purification via CLC Filter Restores Silent Background and Reveal Subtle Faint Audio Details
* The first stage capacitor C1 of the MK9000 quickly absorbs high-frequency noise with premium-grade capacitance components. The middle inductor L is a choke coil that stores magnetic energy through electromagnetic induction. It continuously delivers stable current during large dynamic peaks to strengthen low-frequency extension and control. When handling small signals, the inductor's internal resistance rises automatically as current diminishes, eliminating low-frequency hum caused by reverse current and enabling smoother, more natural dynamic transitions for the MK9000. The final stage capacitor C2 precisely filters residual ripples to reduce hum interference. The combination of 17BE3 full-wave rectification and CLC filter is not a simple stack of components; it represents in-depth optimization tailored for the acoustic properties of 300B tubes. It delivers lower noise, more linear response, and more musical power supply characteristics to create an ideal operating environment for the MK9000's 300B tubes. True premium sound relies on every power cycle of the power supply resonating synchronously with music.

Wide-Band Lossless Transmission Architecture
* A high-power EI-type power transformer custom-engineered exclusively for the 300B tubes of the MK9000. It adopts Class A iron core isolation transformers wound with 180°C heat-resistant QZY polyester imide enameled wire. The premium isolated transformer effectively eases current surges and enhances low-frequency bounce control performance.

Groundbreaking Choice for Acoustic Performance and Design
* Preamp Voltage Amplifier & Phase Inverter Driver Tubes: 6 Imported Vintage 6GH8A Tubes. Six genuine vintage American RCA 6GH8A vacuum tubes are selected, featuring an independent cathode design. They support differential amplification and phase splitting functions to effectively suppress noise interference, and inject moderate second harmonics during amplification to deliver non-linear tonal embellishment to audio signals.
* 17BE3 Rectifier Tubes: Vintage American RCA 17BE3 tubes are deployed for tube-type rectification and overload protection. The independent dual high-voltage circuit cuts power consumption of vacuum tubes and further boosts overall tube timbre. The 17BE3 delivers powerful analytical capability with neutral, straightforward sound characteristics, reproducing more authentic and natural timbre.
* Output Power Amplifier Tubes: 4 Custom UOTANG 300B Tubes. Custom UOTANG 300B tubes power the Class A push-pull amplification paired with direct-coupled long-tailed phase inverter circuit design. It retains the linear advantages of Class A topology and offsets even-order harmonics via symmetrical structure, striking an optimal balance between pristine clarity and powerful output. It delivers delicate, mellow sound that preserves the noble inherent character of 300B tubes, with more controllable explosive power than single-ended designs, achieving an exquisite balance of high fidelity and rich tonal charm.

Adjustable NFB Negative Feedback Technology
* The UOTANG MK9000 supports free switching between two NFB modes, unlocking two completely distinct musical signatures via 0dB and -3dB settings to help you discover your exclusive sonic aesthetic.
* -3dB Mode (Gear 1): Refined, Balanced & Exquisite. Moderate negative feedback is introduced to precisely optimize the frequency response curve, delivering smoother, well-structured sound with soft, pure and mellow tonal characteristics, ideal for vocal, string and similar music genres.
* 0dB Mode (Gear 2): Pure Original Sound, Full Dynamic Range. Negative feedback is completely bypassed to faithfully restore the original harmonic characteristics of vacuum tubes, presenting open, bold and powerful sound that suits music with grand dynamic scenes.

Full-Width Panel, Dual Meters, Dual Functions
* Real-time operating status monitoring at a glance
* Precise fixed bias adjustment
* The MK9000 is equipped with high-precision dual-function stereo UV audio level meters. The meters monitor operating conditions and support bias adjustment, enabling intuitive observation of tube working status and convenient fixed bias tuning.
* Independent external BIAS ADJ controls allow effortless monitoring and fine-tuning of operating parameters.
* The full-width integrated meter panel delivers immersive visual feedback linked to audio details, paired with a black background and soft warm white backlight to convey understated premium texture.

Dual Modes: Power Amp Only/Integrated Amplifier
* The UOTANG MK9000 can operate as a standalone power amplifier, with dual modes balancing ease of use and advanced customization.
* Power Amp Only Mode: Directly connect an independent preamplifier via the Pre In port, compatible with both tube and solid-state preamps. Its 2000mV high-sensitivity input works with 99% of preamplifiers on the market.
* Integrated Amplifier Mode: Directly connect audio sources via dual RCA inputs, balanced inputs and turntable inputs, with a 420mV sensitivity plug-and-play design.

Full-Compatible Interface Design: Adaptable to Diverse Audio Sources
* The MK9000 is equipped with three major input ports: turntable input, dual RCA inputs and balanced inputs. It delivers universal compatibility covering analog audio sources, digital playback devices, home audio systems and professional setups, unlocking premium sound performance for every audio medium.
* Turntable Input: The dedicated PHONO port is custom-built for analog LP turntables to restore the mellow texture of vinyl records. Its exclusive MM input features a precise 51kΩ impedance matching the output characteristics of moving magnet cartridges to eliminate load distortion, fully preserving the micro groove details and analog warmth of vinyl records.
* Dual RCA Inputs: Two groups of CD & AUX dual RCA ports support 99% of mainstream home audio devices including CD players, audio decoders and streaming players. With a 420mV input sensitivity, it offers plug-and-play operation without complicated setup.
* Full Balanced XLR Input: The balanced port adopts a 3-pin XLR structure that transmits differential positive and negative signals to effectively filter electromagnetic interference during signal transmission.

Hand-Wired Chassis for Large Signals + PCB for Small Signals
* The MK9000 combines hand-wired point-to-point construction for high-current large-signal paths with printed circuit boards for delicate small-signal circuits. Custom-tuned for distinct signal properties, this design strikes a balance between anti-interference stability and pure signal integrity, ensuring long-term reliable operation and high-fidelity audio reproduction.
* Large Signal Hand-Wired Chassis: High-current circuits such as power amplification stages and power supply rectification & filtering adopt hand-wired wiring to guarantee stable large-current transmission.
* Small Signal PCB Soldering: Pre-amplification, phase inverter circuits and control modules are laid out on PCBs with optimized signal traces to avoid electromagnetic interference from high-current circuits to delicate small signals.

Power-On Delay Warm-Up Protection
* The UOTANG MK9000 features a built-in warm-up system with approximately 30 seconds of mute after power-on. Integrated power-on delay protection and mute delay protection deliver shock-free power-up timing. Low voltage heats the tube filaments first with high voltage delayed, while low current pre-charges capacitors for energy storage. High voltage ramps up gradually to full level before audio output, enabling sufficient warm-up for all vacuum tubes.

Elegant and Refined Timbre
* It delivers the poised sonic demeanor inherent to pure Class A circuits and the technical advantages brought by direct-coupled architecture. A highly symmetrical differential phase inverter circuit constructs an accurate stereo soundstage with striking dynamic impact. Human vocals sound warm, intimate and uncolored, balancing rich density and natural breathing texture. Dynamic range is reproduced authentically to deliver studio-grade immersive live sound experience.

Recommended Matching UOTANG Speakers
* T806
* T803
* T602
* T605

More Details:
* Premium Texture from Automotive-Grade Body Painting Craft
* Tempered Glass Front Panel Creates Dazzling Visual Echo with Vacuum Tubes
* Pure Aluminum Alloy Infrared Remote Controller with Exquisite Matte Natural Texture: The MK9000 is equipped with a premium metal remote controller for audio volume adjustment.
* Japan ALPS Motorized Potentiometer with High Precision, Low Sonic Contamination: It guarantees balanced sound output between left and right channels, featuring superior linear precision and minimal dynamic noise.
* Independent Audio Relays for Omni-Directional Targeted Protection: Three groups of audio inputs are each fitted with an independent relay, delivering separate protection for every input channel.
* Independent Output Relays Provide Separate Dual-Channel Protection: Each channel is protected by an individual relay, plus an extra grounding relay for the earth wire.
* True Balanced Audio Input Ports Satisfy Demands for Finer Audio Details: It is equipped with XLR balanced audio input jacks to reproduce richer sonic micro-details.
* Spherical Anti-Vibration Feet for Superior Shock Isolation: The MK9000 adopts custom spherical shock-absorbing foot pads for outstanding vibration suppression performance.
* Pure Copper Gold-Plated Terminals for Efficient & Stable Signal Transmission: Low output internal resistance delivers excellent signal conductivity, effectively reducing transmission loss.
* Easy Plug-and-Play Protective Cover with Automotive-Grade Precision Baking Varnish Craftsmanship: Both the main chassis and mesh grille adopt baking varnish finishing, forming an integrated seamless body with a grand visual presence.
* High-Precision Voltage Stabilization Circuit Built with Four Imported Voltage Regulator Tubes: It supplies continuous stable voltage to the entire amplifier unit, delivering rich and powerful low-frequency response, crisp mid-to-high frequencies, and retaining abundant micro-details even under large dynamic swings.
* Premium Imported Brand Capacitors & Japanese 5-Band High-Quality Resistors: It is fitted with German CHIRMCAP audio capacitors, Rubycon, Nichicon and Black Diamond electrolytic & film capacitors that feature high temperature resistance, long service life and low internal resistance.

Specifications:
* Product Dimensions: 430mm(W) x 217mm(H) x 385mm(D) (Including Terminal Posts)
* Rated Output Power: 24W + 24W (RMS Operating Condition)
* Total Harmonic Distortion: ≤1% (1kHz)
* Input Sensitivity: 420mV (Integrated Input)/2000mV (Power Amp Only Input)
* Input Impedance: 100KΩ
* MM Phono Amp Input Impedance: 51KΩ
* MM Phono Amp Voltage Gain: 40dB (1kHz)
* MM Phono Amp RIAA Frequency Response: 0.25dB 20Hz-20KHz
* Output Impedance: 4Ω, 8Ω, 16Ω
* Overall Frequency Response: 18Hz-32kHz (-1.5dB)
* Left/Right Output Balance: <0.5dB
* Signal-To-Noise Ratio: 89dB
* Total Power Consumption: 280W
* Net Weight: 28KG
* Vacuum Tubes: 6 x 6GH8A, 1 x 17BE3, 4 x 300B
* Power Supply Voltage: 220V ±5% (50Hz)

Packing List:
* 1 x Set of Tube Amplifier

Packaging Details:
* Package weight: 30kg