QULOOS MUB5 R2R Portable DAC & Headphone Amplifier (Like New)

Features High-End Portable DAC/AMP. 19+5 Segmented R2R DAC Architecture. Precisely matched Resistors Array with 0.01% Tolerance. Custom Oversampling(OS) and Non-Oversampling(NOS/M1) Modes. Discrete Headphone Amplifier Section with FZT Power Transistors. OPA627 Buffer Stage. Up to 2.5W Per Channel Output. Versatile Functionality With Multiple Input Options(Coaxial, Optical, Bluetooth, and USB Type-C). 3.5mm+4.4mm Headphone Outputs. Line-Out Function Support. 120-Level Precise Volume Adjustment. Touch-Sensitive Display Panel, Physical Volume Knob. Professionally Designed Shielded Power Supply. Up to 8 Hours Battery Backup. QC Fast Charging Support. DC-IN With Battery Bypass Technology. QULOOS MUB5 is a reference-grade portable DAC and Headphone Amplifier designed with a segmented R2R ladder DAC architecture. Quloos has professionally designed a high-precision 19+5 segmented R2R DAC architecture. They have matched resistors with 0.01% tolerance. The MUB5 has a total of 178 resistors that form this full R2R network array and provide high-resolution audio signal processing. It’s designed to bring life to your music with its ultra-clean and rich R2R DAC arrangement, a high-power discrete amplification section, and a clean, NDCS shielded power supply with 20 independent power circuits, LTC6655 voltage reference, and QA661 low-jitter crystal oscillators. Upgrade your portable arsenal with the all-new Quloos MUB5 and unlock pure high-fidelity sonic excellence for yourself!! Pure R2R DAC Architecture QULOOS MUB5 features a 19+5 segmented R2R DAC arrangement. It features 178 precision-matched resistors, which are matched with 0.01% tolerance. This R2R DAC arrangement provides crisp, high-resolution audio signal processing and delivers a rich, musical sound profile with high accuracy and pure high-resolution audio excellence. Customize Your Sound With Two Filter Options QULOOS MUB5 has two filter options, custom Oversampling(OS) and No-Oversampling(NOS/M1). The NOS mode packs an accurate, expansive, and precise sound response, while the NOS mode delivers a relaxed sound response. The NOS mode provides pure sound as it is recorded and shows no colouration from the MUB5. Fully Discrete High-Power Amplification QULOOS MUB5 features a fully discrete headphone amplification section with FZT power transistors and OPA627 chips in the buffer stage. It produces an impressive output thrust reaching up to 1.5W in battery mode and up to 2.5W per channel in 12V DC-in mode. With such a strong output, MUB5 drives most IEMs and Headphones with ease. Even for demanding Headphones, MUB5 works like a charm. Multiple Input, Output Options QULOOS MUB5 is a high-end portable DAC/AMP. It has multiple input and output options, which make the MUB5 a highly versatile device that fits into every scenario. It supports USB, Coaxial, Optical, and Bluetooth connections for input. With 3.5mm and 4.4mm headphone outputs and line-out functionality, the MUB5 can work as a headphone amplifier as well as an adjustable preamp. Clean Power Delivery with Properly Shielded Power Supply Design QULOOS MUB5 gets clean power to each component on the circuitry. The DAC/AMP features a specially designed NDCS shielded power supply with 20 independent power circuits, an LTC6655 voltage reference chip, and QA661 crystal oscillators. With such a clean and efficient power supply design, the MUB5 offers ultra-clean performance with no noticeable interference from the power supply. It has a rated battery life of about 7 to 8 hours and supports the QC fast charging protocol as well. Product Specifications Basic Specifications Dimensions ≈ 138 × 80.5 × 23 mm Weight ≈ 360 g Audio Inputs USB Type-C, RCA Coaxial, Optical, 3.5 mm Line-In, Bluetooth Outputs 3.5 mm Single-ended / 4.4 mm Balanced (switchable PO/LO) DAC Chip In-house developed discrete R2R DAC R2R Buffer OPA627 Headphone Amp FZT power transistor fully discrete headphone amp Digital Output Bluetooth Format Bluetooth 5.0, LDAC, APTX, APTX-HD, AAC, SBC Bluetooth Direction Unidirectional, MUB5 as Bluetooth receiving terminal USB Protocol UAC1.0 / UAC2.0, supports Windows, Mac, Android, iOS USB Sampling Rate Up to PCM 32-bit 384 kHz, DSD512 Optical/Coax Sampling Rate Up to PCM 24-bit 192 kHz, DSD64 (DoP) Technical Specs Line-In Voltage ≤ 2.6 V rms Line Out Voltage (menu adjustable) BAL 4 V & SE 2 V BAL 2.8 V & SE 1.4 V BAL 2 V & SE 1 V Output ADJ (adjustable) Frequency Response (M2 Mode) 20 Hz – 20 kHz (±0.5 dB) THD+N 0.003% (Balanced & Single-ended) SNR 116 dB (Balanced & Single-ended) Dynamic Range 112 dB (Balanced & Single-ended) Channel Separation 104 dB (Balanced & Single-ended) Crosstalk 93 dB (Balanced), 64 dB (Single-ended) Headphone Output Impedance <1Ω (Balanced), <2Ω (Single-ended) Headphone Matching Range 8Ω – 600Ω Output Levels (Vrms) @ Gain=N, VOL=120 5.5 V rms (BAL) / 2.5 V rms (SE) @ Gain=N, VOL=30 2.7 V rms (BAL) / 1.1 V rms (SE) @ Gain=N, VOL=10 7.0 V rms (BAL) / 4.0 V rms (SE) Output Power (mW) Internal Battery (THD=0.1%) 1500 mW + 1500 mW @ 32Ω (BAL, instantaneous) 500 mW + 500 mW @ 32Ω (SE, instantaneous) 320 mW + 320 mW @ 300Ω (BAL, sustained) 80 mW + 80 mW @ 300Ω (SE, sustained) DC12V 2A Input (THD=0.1%) 2500 mW + 2500 mW @ 32Ω (BAL, instantaneous) 900 mW + 900 mW @ 32Ω (SE, instantaneous) 530 mW + 530 mW @ 300Ω (BAL, sustained) 120 mW + 120 mW @ 300Ω (SE, sustained) Battery Battery Life ≈ 8 hours (HPA=PSV≠6V, 16-bit/44.1 kHz playback, DM7Ti earphones, auto screen off) Charging Time ≈ 4–5h (Type-C slow), ≈ 3h (Type-C fast), ≈ 3h (DC 12V ≥2A) External Power Input Type-C (supports fast charge): 5V ≥ 2A, 12V ≥ 1A (QC2.0) DC 12V Input (recommended): 12V ≥ 2A (fast charge, compatible with 5–21V stable supplies, fixed polarity) Charging Equipment Type-C charger (phone charger), DC12V ≥2A power adapter / cable