DB Drive OKUR A7 Series Amplifiers User Manual & Installation Guide

1. OKUR COMPETITION AMPLIFIERS' SPECIFICATION

1-1. OKUR COMPETITION AMPLIFIERS

• Working Voltage: 10~16 Volts for A7 3500L.1; 8.5~18 Volts for A7 3500H.1 & A7 7500.1
• Frequency Response: 20Hz ~ 250Hz
• Signal to Noise Ratio: < 100dB
• Damping Factor: > 250
• Low Level Input: 6V ~ 0.2V
• Low Pass Filter Variable (@ 24dB Slope): 35Hz ~ 250Hz
• Bass Boost @ 45Hz Variable: 0 ~ 9dB
• Subsonic Filter (@ 24dB slope) Variable: 10Hz ~ 50Hz
• Phase Shift Variable: 0 ~ 180 degrees
• Master/slave (Linkable): Yes
• Remote Level Control: Yes
• RCA line Output: Yes
• Minimum working impedance: 1 ohm for single unit, 2 ohm for linked

2. OKUR COMPETITION AMPLIFIER'S CONTROL & CONNECTION

This section describes the amplifier's controls, connection terminals, and indicators.

Controls:

• Gain (6V ~ 0.2V): Adjusts the output voltage from the headunit's RCA line-outs to match the amplifier's input.
• Subsonic Filter (10Hz ~ 50Hz @ 24dB/Oct): Controls the high-pass point for speaker outputs to eliminate damaging low frequencies.
• Bass Boost (0~9dB @ 45Hz): Boosts bass frequencies by 0 to 9dB at 45Hz.
• Remote Level Control Port: For connecting a remote gain level control.
• Low Pass Filter (35Hz ~ 250Hz @ 24dB/Oct): Controls the low-pass point for speaker outputs.
• Phase (0 ~ 180 degree): Adjusts the phase from 0 to 180 degrees.
• Output Master / Input Slave: Used for daisy-chaining multiple OKUR Competition amplifiers to achieve a 2-ohm load.

Connection Terminals:

• +12V (Power Connection): Connect to the positive terminal (+12V) of the battery. Recommended wire gauge is 0 gauge for all models. Ensure battery voltage is checked. External fuses are required as amplifiers are not equipped with them.
• GND (Ground Connection): Connect to the vehicle's negative or ground cables. Recommended wire gauge is 0 gauge for all models. Ensure a clean, direct connection to the vehicle frame.
• REM (Remote Connection): Connect to the switched +12V output from the headunit using a trigger cable.
• Speaker Outputs: Connect to subwoofer speakers. Minimum speaker wire gauge is 12 gauge. Minimum impedance is 1 ohm for single units and 2 ohm for linked connections.

Indicators:

• Power LED: Green light indicates normal operation.
• Protect LED: Red light indicates general malfunction, faulty connection, or thermal protection.

Connection Diagrams:

Textual descriptions of diagrams showing amplifier connections:

• Diagram illustrating +12V, GND, and REM connections to the amplifier, showing the battery, fuse, and remote turn-on cable.
• Diagram showing speaker connections for single units and linked configurations, indicating impedance ranges (e.g., 8~1 ohms, 8~2 ohms).
• Diagram illustrating the multi-linking connection between a master and slave amplifier, including RCA connections and switch settings.

3. INSTALLATION

It is recommended to read this manual carefully before installation. For complex installations, consider consulting a DB Drive or DB Research authorized dealer.

3-1. Mounting Preparation

• Disconnect the negative (-) battery cable before any mounting or connection work.
• Check battery and alternator ground connections for proper contact and absence of corrosion.
• Consider cooling efficiency and safety when selecting a mounting location.

3-2. Mounting Location

• The OKUR amplifiers feature a heatsink for heat dissipation. Mount vertically with heatsink fins exposed for better airflow.
• Choose a dry, well-ventilated location.
• Ensure mounting and cable routing do not interfere with vehicle systems (cables, fuel lines, hydraulic lines, etc.) or pose a hazard.

3-3. +12V, GND, REM Connection

• Power Connection (+12V): Disconnect the negative battery wire before starting. Use minimum 0 gauge cables. Connect to the +12V terminal. Install external fuses within 18 inches of the battery on the positive cable, using appropriate fuse holders for the current draw.
• Ground Connection (GND): Locate a clean, secure grounding point close to the amplifier, directly connected to the vehicle frame. Use the same gauge cable as the power cable.
• Remote Connection (REM): Connect a remote turn-on cable from the headunit's switched +12V output.

3-4. Speaker Connection

• Use minimum 12 gauge speaker connecting cables.
• Route speaker cables away from power and input cables. Use grommets for cables passing through metal.
• Connect to speakers according to terminal types. Strip 3/8" insulation, twist strands tightly, and ensure no stray strands cause shorts.
• Crimp spade lugs or tin cable ends for secure termination.
• Connect cables to the amplifier's speaker outputs as per diagrams.
• Caution: Minimum impedance is 1 ohm for single units and 2 ohms for linked units.

3-5. OKUR COMPETITION AMPLIFIER'S MULTI-LINKING CONNECTION

This allows linking two digital amplifiers to function as one.

• Step 1: Connect the master amplifier to the headunit. Set its output master and input slave switch to the "output master" position.
• Step 2: Connect the master and slave amplifiers using RCA jacks in a daisy-chain fashion.
• Step 3: Set the slave amplifier's output master & input slave switch to the "slave input" position.
• Step 4: Connect the positive (+) speaker cable from the master amplifier to the subwoofer's positive (+).
• Step 5: Connect the positive (+) speaker cable from the slave amplifier to the subwoofer's negative (-).
• Step 6: Connect the negative (-) speaker cable from the master amplifier to the negative (-) speaker cable of the slave amplifier.

Caution: Linked amplifiers have a minimum impedance of 2 ohms. Working voltages are 8.5~16V for A7 3500L.1 and 8.5~18V for A7 3500H.1 and A7 7500.1.

4. TROUBLE SHOOTING

No Sound (No Output)

1. Check all connections, cable routing, shorts, and voltage at the amplifiers and headunit.
2. Check fuses (built-in or external). Replace brown fuses with new ones.
3. Test speakers with another amplifier to ensure they are functional.

Protection Mode

1. Check for overload, overheat (thermal), short circuits, voltage issues, and DC offset.
2. Minimum working impedance: 1 ohm for single units (A7 3500L.1, A7 3500H.1, A7 7500.1) and 2 ohm for linked operation.
3. If the amplifier shuts down due to overheating, reset it by turning off the remote input and allowing it to cool down. Ensure no airflow obstructions around the amplifier.
4. Voltage protection: A7 3500L.1 operates between 8.5V ~ 16V. A7 3500H.1 and A7 7500.1 operate between 8.5V ~ 18V. The amplifier will be protected if voltage is outside these ranges.

Poor Bass Response

1. Check speaker polarity.

Whining Noise

1. Engine noise is often caused by poor grounding of the amplifier, headunit, other components, battery, or alternator. Check all grounding connections.

LIMITED WARRANTY

DB DRIVE warrants the OKUR A7 3500L.1, A7 3500H.1, and A7 7500.1 amplifiers for a period of 90 days from the date of original invoice. This warranty applies to the original purchase only and requires the amplifier to be purchased directly from an authorized DB Drive dealer or DB Research.

This limited warranty does not cover units subjected to misuse, abuse, neglect, or accident. Products showing evidence of alteration, modification, abuse, or unauthorized servicing will be ineligible. The original sales invoice must be presented for any warranty claim. Returned amplifiers will be inspected before warranty agreement is issued. Approved warranty units will be repaired to their original working condition.

For warranty questions or service, please contact DB Research.

DB Research L.L.P.
302 Hanmo re Industrial Parkway // Harlingen, TX 78550
Phone: 877.787.0101 // Website: www.dbdrive.net