1. Introduction
The Technical Pro HB3502U is a versatile audio component designed to integrate amplifier, pre-amplifier, and tuner functionalities into a single unit. It is engineered to deliver robust audio performance with a peak power output of 3500 watts and features a 7.2 channel up-conversion capability. This unit supports multiple audio sources including USB, SD Card, and MP3/iPod players, alongside traditional RCA inputs. It also includes comprehensive microphone controls for karaoke and public address applications, making it suitable for various audio setups from home theaters to mobile DJ rigs.
2. Safety Instructions
- Power Source: Connect the unit only to the specified power supply (110-220V for worldwide usage). Ensure the power outlet is properly grounded.
- Ventilation: Do not block any ventilation openings. Ensure adequate airflow around the unit to prevent overheating. The unit includes efficient forced-air fans for thermal management.
- Water and Moisture: Do not expose the unit to rain, moisture, dripping, or splashing. Do not place objects filled with liquids, such as vases, on the apparatus.
- Heat: Keep the unit away from heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat.
- Cleaning: Unplug the unit from the wall outlet before cleaning. Use a dry cloth for cleaning. Do not use liquid cleaners or aerosol cleaners.
- Servicing: Do not attempt to service this product yourself as opening or removing covers may expose you to dangerous voltage or other hazards. Refer all servicing to qualified service personnel.
- Placement: Place the unit on a stable, level surface. Avoid placing it in direct sunlight or near strong magnetic fields.
3. Features
The HB3502U amplifier is equipped with a range of features designed for comprehensive audio control and playback:
- Power Output: 3500 watts maximum power, suitable for demanding audio setups.
- Channel Configuration: 2-channel amplifier/pre-amplifier with AM/FM tuner, supporting 4 main speaker outputs and 3 surround sound speakers.
- Rack Mountable Design: Features a 2-rack space rugged metal chassis with handles and removable rack-mountable ears for professional installation.
- Multiple Inputs: Front panel USB, SD Card, and MP3 inputs. Rear panel includes 2-channel and 5.1 channel RCA inputs.
- Microphone Inputs: Two microphone inputs with individual volume, bass, treble, and echo controls, plus a dual karaoke mic mixer.
- Output Options: Banana binding post outputs for up to four full-range speakers, push-button surround outputs, two mono RCA dedicated subwoofer outputs, and one RCA dedicated pre-amp output.
- Advanced Controls: Separate pre-amplifier and subwoofer gain controls for precise frequency output management.
- Cooling System: Efficient forced-air fans to prevent excessive thermal buildup during operation.
- Display: Digital fluorescent output display meter for visual feedback.
- Voltage Compatibility: 110-220V for worldwide usage.
4. Setup
Before operating your Technical Pro HB3502U amplifier, follow these steps for proper setup.
4.1 Front Panel Overview
4.2 Power Connection
- Ensure the amplifier's power switch is in the OFF position.
- Connect the power cord to the AC inlet on the rear panel of the amplifier.
- Plug the other end of the power cord into a suitable 110-220V AC power outlet.
4.3 Speaker Connections
The HB3502U supports various speaker configurations:
- Main Speakers: Use the banana binding post outputs on the rear panel to connect up to four full-range speakers. Ensure correct polarity (+ to + and - to -).
- Surround Sound Speakers: Utilize the push-button surround outputs for connecting your surround sound speaker set.
- Subwoofers: Connect powered subwoofers to the two mono RCA dedicated subwoofer outputs on the rear panel.
4.4 Audio Input Connections
- USB/SD Card: Insert a USB flash drive or SD/MMC card into the respective slots on the front panel for digital audio playback.
- MP3/iPod: Connect your MP3 player or iPod to the front panel 3.5mm input jack (labeled HEADPHONES, often used as an auxiliary input).
- RCA Inputs: Use the RCA inputs on the rear panel for connecting external audio sources such as CD players, DVD players, or other audio devices. The unit supports both 2-channel and 5.1 channel RCA inputs.
4.5 Microphone Connections
Connect up to two microphones to the MIC 1 and MIC 2 input jacks on the front panel.
4.6 Rack Mounting (Optional)
The HB3502U comes with removable rack mount brackets. Attach these brackets to the sides of the unit using the provided screws if you intend to install the amplifier into a standard audio rack.
5. Operating Instructions
This section details how to operate the various functions of your HB3502U amplifier.
5.1 Powering On/Off
- To power on the unit, press the POWER button located on the front panel. The digital display will illuminate.
- To power off, press the POWER button again.
5.2 Input Selection
Use the INPUT FUNCTION buttons on the front panel to select your desired audio source:
- Press the corresponding button for USB, SD/MMC Card, AM/FM, or other line inputs (e.g., DVD for RCA inputs).
5.3 Volume Controls
- Master Volume: Adjust the large MASTER VOLUME knob on the right side of the front panel to control the overall output level of the amplifier.
- Pre Out: Use the PRE OUT knob to adjust the volume level for the pre-amplifier output, useful when connecting to another amplifier.
- Sub Out: Use the SUB OUT knob to adjust the volume level for the dedicated subwoofer outputs.
5.4 Microphone Controls
When using microphones, adjust the following controls:
- MIC VOL: Adjusts the overall volume of the connected microphones.
- MIC BASS: Controls the low-frequency response of the microphone audio.
- MIC TREBLE: Controls the high-frequency response of the microphone audio.
- MIC ECHO: Adds an echo effect to the microphone audio.
5.5 AM/FM Tuner Operation
Select the AM/FM input using the INPUT FUNCTION buttons. Use the tuning controls (usually indicated by arrow buttons or a dedicated tuning knob, though not explicitly labeled in the image, standard for tuners) to find and select radio stations. The digital display will show the frequency.
5.6 USB/SD Card Playback
Once a USB drive or SD card is inserted and the corresponding input is selected, the unit should automatically begin playback or allow navigation through files using the control buttons (e.g., play/pause, skip forward/backward).
6. Maintenance
- Cleaning: Regularly wipe the unit with a soft, dry cloth to remove dust. Do not use abrasive cleaners or solvents.
- Ventilation: Ensure that the ventilation openings are clear of dust and debris to maintain proper cooling.
- Storage: If storing the unit for an extended period, disconnect it from the power supply and store it in a cool, dry place.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| No power | Power cord not connected; power outlet faulty; unit power switch off. | Check power cord connection; try a different outlet; ensure power switch is ON. |
| No sound output | Incorrect input selected; volume too low; speakers not connected properly; faulty audio cable. | Select correct input source; increase Master Volume; check speaker connections and polarity; replace audio cables. |
| Distorted sound | Volume too high (clipping); faulty speakers or cables; input source distortion. | Reduce Master Volume; check speakers and cables for damage; test with a different audio source. |
| Microphone not working | Microphone not connected; MIC VOL knob too low; faulty microphone. | Ensure microphone is fully plugged in; increase MIC VOL; test with a different microphone. |
| Unit overheating | Blocked ventilation; prolonged high-volume use. | Ensure ventilation openings are clear; reduce volume or allow unit to cool down. |
8. Specifications
| Model Number | HB3502U |
| Brand | Technical Pro |
| Maximum Power Output | 3500 watts |
| Channel Configuration | 7.2 channel up-conversion (2-channel Amp/Pre-amp/AM-FM Tuner) |
| Inputs | USB, SD Card, MP3/iPod (front panel), 2-channel RCA, 5.1 channel RCA (rear panel), 2 Mic inputs |
| Outputs | 4 Main Speaker (banana binding post), 3 Surround Sound Speakers (push-button), 2 Mono RCA Subwoofer, 1 RCA Pre-amp, 1 RCA Record Line Out |
| Dimensions (L x W x H) | 13 x 19 x 3.5 inches |
| Item Weight | 19 pounds |
| Power Supply | 110-220V (selectable/auto-sensing) |
| Included Accessories | Remote control, removable rack mount brackets, 2 AAA batteries |
9. Warranty and Support
For warranty information and technical support, please refer to the documentation included with your purchase or visit the official Technical Pro website. Keep your proof of purchase for any warranty claims.
