Introduction and Overview
The Technical Pro H502URBT is a versatile digital hybrid amplifier designed to deliver powerful and clear audio performance. It integrates a preamp tuner, USB and SD card playback, Bluetooth connectivity, and FM radio, making it suitable for a wide range of audio applications from home entertainment to professional setups. This manual provides detailed instructions for setting up, operating, and maintaining your amplifier to ensure optimal performance and longevity.

Figure 1: Front view of the H502URBT Amplifier.

Figure 2: Rear view of the H502URBT Amplifier, showing connections.
Key Features
The H502URBT amplifier is equipped with a comprehensive set of features to enhance your audio experience:
- High Power Output: 3500 watts peak power for robust sound delivery.
- Multiple Audio Inputs: RCA (2 audio sources), USB, SD Card, MP3 (3.5mm) for diverse connectivity.
- Versatile Outputs: Banana binding post (4 speakers), push button (surround sound speakers), RCA (record line, preamp, 2 mono to subwoofer), Headphone (3.5mm).
- Digital Media Playback: Plays .mp3, .wav, .wma files from USB drives and SD Cards (max 32GB).
- iPod/iPhone Compatibility: USB input allows direct connection for iPods.
- Recording Function: Records .wav files onto USB Flash Drive or SD Card from Tuner & RCA inputs (128 kbps / 44.1 KHz sampling rate).
- Bluetooth Connectivity: Features Bluetooth v2.0 with EDR (2.4 GHz) for wireless connection to A2DP stereo Bluetooth devices, with a range of 30 feet.
- Integrated Tuner: AM/FM digital tuner.
- Microphone Inputs: Dual 1/4'' mic inputs with independent volume, echo, bass, and treble controls.
- Audio Controls: Bass, treble, and balance controls, separate gain control for preamp and subwoofer outputs.
- Display: Digital FL readout with spectrum display.
- Convenience: Built-in Speaker selector, cooling speed fan, removable rack-mount brackets, wireless remote included.

Figure 3: Key features and connectivity options.
Physical Overview
Front Panel Controls and Indicators

Figure 4: Front Panel Layout.
- Power Button: Turns the unit on or off.
- Input Selector: Cycles through RCA, USB, SD, MP3, Bluetooth, and FM inputs.
- USB/SD Card Slots: For playing media files from USB drives and SD cards.
- MP3 Input (3.5mm): Connect external audio devices.
- Headphone Output (3.5mm): For private listening.
- Microphone Inputs (1/4''): Connect up to two microphones.
- Mic Volume/Echo/Bass/Treble Controls: Adjust microphone audio.
- Master Volume: Controls the overall output volume.
- Bass/Treble/Balance Controls: Adjust audio tone and channel balance.
- Digital FL Readout: Displays current status, track information, and spectrum analysis.
Rear Panel Connections

Figure 5: Rear Panel Connections.
- RCA Audio Inputs (L/R): Connect external audio sources like CD players, DVD players, or other audio devices.
- Speaker Outputs (Banana Binding Post): Connect main speakers.
- Surround Sound Speaker Outputs (Push Button): Connect surround sound speakers.
- RCA Record Line Output: For connecting to a recording device.
- RCA Preamp Output: For connecting to an external power amplifier.
- RCA Subwoofer Outputs (Mono): Connect to powered subwoofers.
- FM Antenna Input: Connect the included FM antenna for radio reception.
- Power Input: Connect the AC power cord.
Setup
1. Connecting Speakers
- Ensure the amplifier is turned off and unplugged from the power outlet.
- Connect your main speakers to the "SPEAKER OUTPUT" banana binding posts on the rear panel. Ensure correct polarity (red to red, black to black).
- If using surround sound speakers, connect them to the "SURROUND OUTPUT" push button terminals, observing polarity.
- For powered subwoofers, connect them to the "SUB OUT" RCA outputs.
2. Connecting Audio Sources
- For external audio devices (e.g., CD player, TV), connect their RCA audio outputs to the "RCA INPUT" jacks on the rear panel.
- For portable devices, use the 3.5mm MP3 input on the front panel.
- For USB drives or SD cards, insert them into the respective slots on the front panel.
- Connect the FM antenna to the "FM ANTENNA" terminal for radio reception.
3. Power Connection
- Once all audio and speaker connections are made, plug the amplifier's power cord into a standard AC power outlet.

Figure 6: Example of a typical home audio setup.
Operating Instructions
1. Power On/Off
Press the POWER button on the front panel or the remote control to turn the amplifier on or off. The digital display will illuminate when the unit is powered on.
2. Input Selection
Press the INPUT button on the front panel or the remote control to cycle through the available audio sources: RCA, USB, SD, MP3, Bluetooth, and FM. The selected input will be displayed on the digital readout.
3. Bluetooth Operation
- Select the Bluetooth input using the Input Selector.
- On your Bluetooth-enabled device (e.g., smartphone, tablet), enable Bluetooth and search for available devices.
- Select "Technical Pro H502URBT" from the list of devices to pair.
- Once paired, you can stream audio wirelessly from your device to the amplifier.
4. USB/SD Playback
- Insert a USB flash drive or SD card (up to 32GB) containing .mp3, .wav, or .wma files into the corresponding slot on the front panel.
- Select the USB or SD input.
- The amplifier will automatically begin playing the media. Use the playback controls (Play/Pause, Next/Previous Track) on the front panel or remote. Track title, number, and elapsed time will be displayed.
5. Microphone Usage
- Plug 1/4'' microphones into the MIC1 or MIC2 inputs on the front panel.
- Adjust the MIC VOL, MIC ECHO, MIC BASS, and MIC TREBLE knobs to achieve the desired sound.
6. Recording Function
The amplifier can record audio from the Tuner or RCA inputs directly to a connected USB flash drive or SD card as .wav files. To record, ensure a USB drive or SD card is inserted, select the desired input source, and initiate recording via the appropriate control (refer to the full manual for specific recording button location if not explicitly labeled).
7. Tone and Volume Controls
Use the MASTER VOLUME knob to adjust the overall sound level. The BASS, TREBLE, and BALANCE knobs allow you to fine-tune the audio output to your preference.
Maintenance
Proper maintenance ensures the longevity and optimal performance of your amplifier.
- Cleaning: Disconnect the power before cleaning. Use a soft, dry cloth to wipe the exterior of the unit. Do not use liquid cleaners or aerosol sprays, as they may damage the finish or internal components.
- Ventilation: Ensure that the ventilation openings on the amplifier are not blocked. Adequate airflow is crucial to prevent overheating.
- Storage: If storing the unit for an extended period, keep it in a cool, dry place away from direct sunlight and extreme temperatures.
Troubleshooting
If you encounter issues with your amplifier, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No power | Power cord not securely connected; Power outlet not active; Unit fuse blown. | Check power cord connection; Test outlet with another device; Consult a qualified technician for fuse replacement. |
| No sound output | Incorrect input selected; Speaker wires loose or incorrectly connected; Volume too low; Mute function active. | Select correct input; Check all speaker connections and polarity; Increase Master Volume; Ensure unit is not muted. |
| Bluetooth not connecting | Amplifier not in Bluetooth mode; Device too far; Device already paired with another unit. | Ensure amplifier is on Bluetooth input; Move device closer; Disconnect device from other Bluetooth connections and try again. |
| USB/SD playback issues | Unsupported file format; USB/SD card corrupted; Card size exceeds 32GB. | Ensure files are .mp3, .wav, or .wma; Try a different USB/SD card; Use a card within the 32GB limit. |
| Distorted sound | Volume too high; Speaker impedance mismatch; Poor cable connection. | Reduce volume; Ensure speakers match amplifier impedance; Check all audio cable connections. |
Specifications
Detailed technical specifications for the Technical Pro H502URBT Digital Hybrid Amplifier:
| Feature | Detail |
|---|---|
| Peak Power | 3500 Watts |
| Product Dimensions | 19.1 x 14 x 18 inches |
| Item Weight | 14.9 pounds |
| Model Number | H502URBT |
| Connectivity Technology | RCA, Bluetooth, USB |
| Controller Type | Android (compatible) |
| Compatible Devices | Speaker, iPod, iPhone |
| Audio Output Mode | Mono (for subwoofer), Stereo |
| Surround Sound Channel Configuration | 7.2 Channel up conversion |
| USB & SD Card Max Size | 32GB |
| Recording Format | .wav (128 kbps / 44.1 KHz) |
| Bluetooth Version | v2.0 with EDR |
| Bluetooth Range | 30 Feet |
| Color | Black |

Figure 7: Product Dimensions.
Warranty and Support
Technical Pro products are manufactured with high standards and undergo rigorous quality control. This product is covered by a manufacturer's warranty against defects in materials and workmanship. For specific warranty terms and conditions, please refer to the warranty card included with your purchase or visit the official Technical Pro website.
For technical support, troubleshooting assistance, or service inquiries, please contact Technical Pro customer service. Contact information can typically be found on the Technical Pro website or in your product packaging.





