1. Bubuka
The KGUSS TOPPING DX3pro+ is a high-performance Digital-to-Analog Converter (DAC) and Headphone Amplifier (HPA) designed for high-fidelity audio. It features multiple input options including USB, optical, coaxial, and Bluetooth, along with line out and headphone amplifier outputs. Equipped with an ES9038Q2M DAC chip and XMOS XU208 USB interface, it supports high-resolution audio up to 32-bit/768kHz PCM and DSD512. The integrated NFCA headphone amplifier circuit provides powerful and clean output for various headphones. This manual provides detailed instructions for optimal use.
2. Eusi Paket
Pastikeun yén sadaya item anu didaptarkeun di handap kalebet kana pakét anjeun:
- DX3pro+ Unit
- DC15V / 1A adaptor kakuatan
- Kadali jauh
- Kabel USB
- Anteneu Bluetooth
- Manual pamaké
- Kartu Garansi

Figure 2.1: Contents of the DX3pro+ package.
3. Produk Langkungview
3.1 Panel payun

Figure 3.1: Front panel of the DX3pro+.
- Kaluaran Headphone 3.5mm: Sambungkeun headphone anjeun didieu.
- Layar LED: Displays current status, input, volume, and samplaju le.
- Panarima Remote Control: Pikeun narima sinyal ti remot kontrol.
- Volume Knob / Multi-function Button: Rotate to adjust volume; press to switch inputs or enter settings menu.
3.2 Panel tukang

Figure 3.2: Rear panel of the DX3pro+.
- RCA Output (Rout, Lout): Right and Left channel single-ended RCA outputs for connecting to an amplifier atawa speaker aktif.
- Coaxial SPDIF Input (COAX 1, COAX 2): Two coaxial digital audio inputs.
- Optical SPDIF Input (OPTICAL): One optical digital audio input.
- USB Input (USB): Connect to a computer or compatible media player for USB DAC functionality.
- Bluetooth Antenna (ANT): Connect the provided Bluetooth antenna for wireless audio reception.
- Input Daya (DC15V): Connect the DC15V/1A power adapter here.
4. Setélan
4.1 Sambungan Daya
Connect the provided DC15V/1A power adapter to the "DC15V" input on the rear panel of the DX3pro+, then plug the adapter into a power outlet. The device will enter standby mode, and the screen will display a bright spot.
Video 4.1: Demonstrates the power connection and initial setup steps for the DX3pro+.
4.2 Sambungan Input
Connect your audio source devices to the corresponding inputs on the rear panel:
- USB: Use the supplied USB cable to connect the DX3pro+ to your computer or a compatible media player. Ensure your device supports OTG external sound card functionality if connecting to a mobile phone or tablet.
- Optik/Coaxial: Connect digital audio sources such as CD players, game consoles, or TVs using optical or coaxial cables.
- Bluetooth: Screw the Bluetooth antenna onto the "ANT" connector. Pair your Bluetooth-enabled device (phone, tablet, laptop) with the DX3pro+ to stream audio wirelessly.

Figure 4.1: Connecting the DX3pro+ to a mobile device via USB for high-performance DAC functionality.
5. Parentah Operasi
5.1 Power On/Off and Standby
- Daya Hurung: Connect the power supply. The device will automatically power on and enter standby state, indicated by a bright spot on the screen.
- Antosan: When the device is working, press and hold the volume knob on the front panel to enter standby state. To exit standby, press the knob again or use the remote control.
5.2 Pamilihan Input
Press the volume knob on the front panel to cycle through available input channels (USB, OPT, COAX1, COAX2, BT). The selected input will be displayed on the screen.
5.3 Volume adjustment
Rotate the volume knob on the front panel to adjust the output volume. The volume can also be adjusted using the remote control.
5.4 Setélan Menu
To enter the setup menu, press and hold the volume knob when the power is off, then power up the unit. Rotate the knob to navigate between settings and press to confirm. Press and hold the knob until "8-8" is displayed to save settings.
- PCM Filter Setting (F-1 to F-5): Adjust PCM filter characteristics.
- Screen Brightness Setting (L-1 to L-3): Saluyukeun kacaangan tampilan.
- Automatic Standby Setting (A-O, A-C): Enable or disable automatic standby.
- Line Out Channel Setting (O-1 to O-3): Select output channel mode (Headphone amp, Headphone amp + Line out, Line Out).
- Output Mode Setting (m-P, m-d): Select between Pre-amp mode (volume adjustable) or DAC mode (fixed 2Vrms output).
- Headphone Amp Gain (GAIN +6dB, +19dB): Adjust headphone amplifier gain for different headphone sensitivities.
- Bluetooth Setting (BT ON, BT OFF): Aktipkeun atawa mareuman Bluetooth.
Video 5.1: Demonstrates how to navigate and adjust settings in the DX3pro+ menu.
6. Fitur sareng Spésifikasi
6.1 Fitur konci
- High-performance DAC with USB, optical, coaxial, and Bluetooth inputs.
- ES9038Q2M DAC chip for high-resolution audio.
- XMOS XU208 for USB input, supporting PCM up to 32-bit/768kHz and native DSD512.
- NFCA headphone amplifier circuit with two gain settings (+6dB, +19dB).
- Bluetooth 5.0 with LDAC, AAC, SBC, APTX, APTX LL, and APTX HD protocols.
- Multiple output modes: Headphone amp, Headphone amp + Garis kaluar, DAC, sareng Pra-amppangagung.
- Digital volume adjustment with no channel imbalance.

Figure 6.1: Key features and improvements of the DX3pro+ model.
6.2 Spésifikasi Téknis
| Spésifikasi | Nilai |
|---|---|
| merek | KGUSS |
| Nomer modél | TOPPING DX3pro+ |
| Diménsi | 16.5cm L x 12.0cm W x 4.0cm H (6.5"L x 4.72"W) |
| Item Beurat | 420g (0.93 lbs) |
| Bahan | alumunium |
| Maksimum Suplai Voltage | 15 volt |
| Tipe panganteur | Coaxial, USB, Optical, Bluetooth |
| USB IN (PCM) | 44.1kHz-768kHz / 16bit-32bit |
| USB IN (DSD) | DSD64-DSD512 (Native), DSD64-DSD256 (DoP) |
| COAX / OPT IN | 44.1kHz-192kHz / 16bit-24bit, DSD64 (DoP) |
| BT IN | AAC / SBC / APTX / APTX LL / APTX HD / LDAC |
| THD+N @1kHz (A-wt) | <0.00015% (RCA Out), <0.00015% (HP Out @1500mW (32Ω)) |
| SNR @1kHz (A-wt) | 122dB (RCA Out), 120dB (HP Out) |
| Output Power (HP Out) | 1800mW x 2 @32Ω THD+N<0.1%, 900mW x 2 @64Ω THD+N<0.1%, 250mW x 2 @300Ω THD+N<0.1% |

Figure 6.2: Comprehensive technical specifications for the DX3pro+.
7. Cara ngungkulan
This section addresses common issues you might encounter with your DX3pro+ and provides solutions. For more detailed troubleshooting, refer to the official support resources.
Video 7.1: Official troubleshooting guide for the TOPPING DX3pro+.
Masalah umum sareng Solusi:
| Fenomena | Solusi |
|---|---|
| Can't be turned on |
|
| Taya sora |
|
| Maén deui ribut |
|
| One channel with noise/no output |
|
| Channel imbalance |
|
| Teu tiasa nyapasangkeun Bluetooth |
|
| Bluetooth in: the sound is cut off |
|
| The connected USB device does not recognize this unit |
|
| Kadali jauh teu ngabales |
|
| The sample rate displayed on the device does not match the music file |
|
| HP -3 |
|
| DFU |
|
| HP ERR |
|
| IN Err / INH Err / INL Err |
|
| d-3 |
|
| Can't adjust this unit's volume |
|
8. Garansi jeung Rojongan
KGUSS and HIFI College are committed to customer satisfaction. We offer the following support:
- 30 poé jaminan duit-balik pikeun alesan naon.
- More than 12-month warranty on all quality defects.
- Ngarojong 30-day price matching.
- For any questions or support, please contact HIFI College at HIFICOLLEGE@gmail.com.
HIFI College is an authorized distributor for KGUSS, TOPPING, GUSTARD, and FX-AUDIO/xDuoo products, ensuring authenticity and reliable support.
