rolls REQ215 Dual 15-Band Graphic Equalizer User Manual

1. Introduction

The rolls REQ215 is a dual 15-band graphic equalizer designed for modern sound reinforcement applications. It provides precise control over audio frequencies, allowing for detailed sound shaping and acoustic correction. The unit features smooth band-pass filtering and transparent low-noise circuitry, ensuring virtually distortion-free operation.

This manual provides essential information for the proper setup, operation, and maintenance of your REQ215 equalizer. Please read it thoroughly before using the device.

2. Safety Information

Important Safety Instructions:

• Do not expose this equipment to rain or moisture. To reduce the risk of electric shock, ensure the unit is kept dry.
• Do not remove the back cover. There are no user-serviceable parts inside. Refer all servicing to qualified service personnel.
• Ensure the unit is connected to a grounded AC power outlet.
• Avoid placing the unit near heat sources such as radiators, heat registers, stoves, or other apparatus (including amplifiers) that produce heat.
• Clean only with a dry cloth.
• Use only attachments/accessories specified by the manufacturer.

3. Product Features and Controls

3.1 Front Panel Overview

The front panel of the REQ215 provides all the controls and indicators necessary for adjusting your audio signal.

Figure 3.1: Front Panel of the rolls REQ215. This image displays the two independent equalizer channels, each with 15 frequency band sliders, a master level control, an In/Out bypass switch, and a vertical LED meter for signal level monitoring.

• Frequency Sliders (20Hz - 20kHz): Each channel features 15 sliders, allowing for precise boost or cut of specific frequency bands. These are ISO standard 2/3 octave frequency centers.
• Level Controls: A rotary knob for each channel to adjust the overall output level.
• In/Out Switch: A bypass switch for each channel to engage or disengage the equalization effect. When 'Out', the signal passes through unaffected.
• LED Level Indicators: A series of LEDs for each channel indicating signal levels at +17, +10, 0, -7, and -13 dB. These help monitor input/output levels and prevent clipping.

3.2 Rear Panel Connections

The rear panel houses all the input and output connections, as well as the power inlet.

Figure 3.2: Rear Panel of the rolls REQ215. This image shows the AC power input, serial number label, and the audio input/output connectors. Each of the two channels has both balanced XLR and unbalanced RCA input and output jacks.

• AC Power Inlet: Standard IEC power connector for connecting the unit to mains power.
• Serial Number: Unique identifier for the unit.
• Channel 1 Input (XLR & RCA): Connect your audio source for Channel 1 here. Both balanced XLR and unbalanced RCA connections are provided.
• Channel 1 Output (XLR & RCA): Connect the processed audio from Channel 1 to your amplifier or mixer here. Both balanced XLR and unbalanced RCA connections are provided.
• Channel 2 Input (XLR & RCA): Connect your audio source for Channel 2 here. Both balanced XLR and unbalanced RCA connections are provided.
• Channel 2 Output (XLR & RCA): Connect the processed audio from Channel 2 to your amplifier or mixer here. Both balanced XLR and unbalanced RCA connections are provided.

4. Setup

Follow these steps to properly set up your REQ215 equalizer:

1. Power Connection: Ensure the REQ215 is powered off. Connect the provided AC power cord to the AC Power Inlet on the rear panel and then to a suitable grounded electrical outlet.
2. Audio Input Connection: Connect your audio source (e.g., mixer output, preamplifier output) to the Channel 1 Input and Channel 2 Input on the rear panel. You can use either balanced XLR cables or unbalanced RCA cables, depending on your equipment. For optimal signal integrity, use balanced XLR connections if available.
3. Audio Output Connection: Connect the Channel 1 Output and Channel 2 Output of the REQ215 to the inputs of your next audio component (e.g., power amplifier, main mixer inputs). Again, use either balanced XLR or unbalanced RCA cables consistently with your setup.
4. Initial Settings: Before powering on, ensure all frequency sliders are set to their center (0 dB) position. Set the Level controls to their minimum position. Ensure the In/Out switches are in the 'Out' (bypass) position.

5. Operating Instructions

Once the REQ215 is properly connected, follow these steps for operation:

1. Power On: Turn on all connected audio equipment, starting with your source and ending with your power amplifier. Finally, power on the REQ215.
2. Set Levels: Play an audio signal through the system. Gradually increase the Level controls on the REQ215 until the LED meters show appropriate signal levels, ideally peaking around 0 dB. Avoid consistent illumination of the +17 dB LED, which indicates clipping.
3. Engage Equalization: Flip the In/Out switches to the 'In' position to engage the graphic equalizer for each channel.
4. Adjust Frequencies: Move the frequency sliders up to boost a frequency band or down to cut it. Make small adjustments and listen carefully to the effect on the audio.
5. Common Applications:
   • Room Correction: Adjust specific frequencies to compensate for acoustic anomalies in a listening environment.
   • Feedback Suppression: Identify and cut problematic frequencies that cause audio feedback.
   • Tone Shaping: Enhance or reduce certain frequency ranges to achieve a desired sonic character for instruments or vocals.
6. Power Off: When finished, power off your system in reverse order: power amplifier first, then the REQ215, and finally your audio source.

6. Maintenance

To ensure the longevity and optimal performance of your REQ215:

• Cleaning: Wipe the unit with a soft, dry cloth. Do not use liquid cleaners or solvents.
• Environment: Operate the unit in a clean, dry environment, away from excessive dust, moisture, and extreme temperatures.
• Ventilation: Ensure adequate airflow around the unit to prevent overheating. Do not block ventilation openings.
• Cable Management: Periodically check all audio and power cables for damage or loose connections.

7. Troubleshooting

If you encounter issues with your REQ215, refer to the following common problems and solutions:

• No Power:
  • Check if the power cord is securely connected to both the unit and the electrical outlet.
  • Verify that the electrical outlet is functional.
• No Sound Output:
  • Ensure all audio cables are correctly connected to the inputs and outputs.
  • Check that the In/Out switches are in the 'In' position (or 'Out' if you expect bypass).
  • Verify that the Level controls are not set to minimum.
  • Confirm that the audio source is sending a signal and the receiving equipment (amplifier/mixer) is functioning correctly.
• Distortion or Unwanted Noise:
  • Reduce the input or output Level controls to prevent clipping (indicated by the highest LED levels).
  • Ensure all cable connections are secure and not damaged.
  • Check for ground loops by ensuring all equipment is properly grounded.
  • If using unbalanced cables, try balanced XLR cables for better noise rejection.
• Uneven Channel Levels:
  • Adjust the individual Level controls for each channel to balance the output.
  • Ensure all frequency sliders are set symmetrically if a flat response is desired.

8. Specifications

9. Warranty and Support

For warranty information and technical support, please refer to the documentation included with your purchase or visit the official rolls website. Contact their customer service for assistance with any issues not covered in this manual.