RAM Audio DUBHE Series Professional Power Amplifiers

Safety Precautions

WARNING:

The lightning and arrowhead symbol ⚡️ warns about the presence of uninsulated dangerous voltage.

When the device is installed, the plug connected into the socket-outlet shall be easily accessible.

This device must be grounded/earthed.

Connections of the amplifier to the loudspeakers shall be done by a skilled person.

Read this manual before using the device.

Mounting Instructions

Take into account that airflow to cool these devices is from their rear side to their front side.

Please make sure that there are no objects at the front or rear of the device (ensure a completely open space at the front and at the back) to ensure an optimal airflow and a correct functioning of the cooling system.

Objects at the right and left sides of the device have to be further than 2 centimeters away.

General Information

1.1 Introduction

The DUBHE Series are 4-channel high power level amplifiers designed for the tough requirements of the touring market. Their high efficiency is remarkable.

The design incorporates the advanced RAM Audio Power Control Management (PCMTM) to configure how power is shared between channels according to user needs, allowing for maximum power to be obtained in a single channel.

Optional AES67, Dante™ Networking, and GPIO are available for DUBHE amplifiers.

1.2 Main Characteristics

• Optional GPIO.
• High efficiency Class D topology.
• Universal power supply with PFC.
• 4-channel models ranging from 2500W up to 10000W.
• Operation at 8/4/2 Ohm low impedance and 100/70/50/35V high impedance.
• RAM Audio advanced Power Control Management (PCMTM).
• Phoenix connectors for inputs and outputs.
• Removable dust filter foam.
• Up-side-down design to prevent fan dust accumulation.
• Temperature-controlled, front-to-back cooling fan.

Controls: Where and What?

2.1 Front Panel

Figure 1 Description: The front panel features four channels (CH-A, CH-B, CH-C, CH-D), each with indicator LEDs for CLIP, SIGNAL, and FAULT. A POWER section includes STBY (Standby) and ON indicators. The RAM Audio logo and model designation are also visible.

• 1. CLIP LED: Indicates Intelligent Clip Limiter operation (see page 12).
• SIGNAL LED: Indicates presence of signal at the inputs.
• FAULT LED: Indicates active temperature protection (red).
• 2. Main Power Switch: The illuminated main power switch.

2.2 Rear Panel

Figure 2 Description: The rear panel contains signal inputs, output level controls, configuration switches (minidips), and speaker outputs.

• 1. Signal Input: Phoenix type 3.5mm-pitch connectors for amplifier signal input.
• 2. Signal Attenuation Level Control Knobs: Permit independent control of each channel's attenuation in 21 steps.
• 3. Link Minidips: Used to link an input to an adjacent input and use the same input signal.
• 4. Gain Selection Minidips: Configure amplifier gain from 26dB to 40dB in 2dB steps (default setting 32dB).
• 5. Configuration Minidips: Configure the 50Hz Subsonic Filter, Output Mode (Low Impedance: 8/4/2 Ohm; High Impedance: 100/70/50V), and Bridge Mode.
• 6. Speaker Connectors: Phoenix type 7.62mm-pitch connectors for connecting speakers.
• Mains Power Input: IEC C19 male connector for connecting the amplifier to the mains network.

Installation and Operation

3.1 Connections

Plug the amplifier into a properly earthed mains socket (90-265V AC).

The input signal fed to the amplifier can be either balanced or unbalanced. The following describes both methods for wiring a Phoenix type 3.5mm-pitch connector:

Balanced Signal: Connect pin ⏚ to Ground, pin + to Signal + (hot), and pin - to Signal - (cold).

Unbalanced Signal: Connect Pin ⏚ to Ground, pin + to Signal, and pin - to Ground.

Important! If a connection is made with an unbalanced line and pin - on the Euro style connector is not connected to ground, a 6 dB loss occurs in the line, and only a quarter of the amplifier's power is produced.

3.1.1 DUAL Channel Mode (Stereo)

Connect the signal lines to the Phoenix type 3.5mm-pitch connectors.

Connect the speakers' lines to the corresponding Phoenix type 7.62mm-pitch connectors on the amplifier, respecting the polarity.

Diagram Description (Figure 3): Illustrates two speakers connected to individual channels (e.g., CH-1, CH-2). Signal inputs are connected to the respective channels. Polarity must be observed for speaker connections.

3.1.2 LINK Channel Mode

Operate as in Dual Channel Mode, but with the signal input linked to an adjacent channel.

Diagram Description (Figure 4): Shows signal input linked from one channel to an adjacent one, allowing a single input signal to drive multiple channels.

3.1.3 BRIDGE Channel Mode

Connect the signal lines to the Phoenix type 3.5mm-pitch connectors.

Connect the speaker line to the Phoenix type 7.62mm-pitch connector wired to the + and - terminals between the bridged channels.

ATTENTION! The "-" pins do not have to be Ground!

Diagram Description (Figure 5): Depicts a single speaker connected across two bridged channels. The speaker is wired to the positive terminal of one channel and the negative terminal of the other. Specific wiring for bridged operation is shown.

3.2 Configuration

DUBHE amplifiers feature minidip switches on the rear panel for independent configuration of each channel:

• Gain: A combination of 3 minidips configures amplifier gain from 26dB to 40dB in 2dB steps.
• Subsonic Filter: A high-pass filter can be configured at 50Hz for each channel.
• Output Mode: 2 minidips per channel select Hi Impedance voltage (for 100/70/50V lines) and Low Impedance power limitation (at 8/4/2 Ohm).
• Bridge Mode: 2 minidips per channel pair are used to bridge channels.

Silk-screened legends next to the minidips indicate their positions for each configuration.

Signal Setup:

• Input Link: 6 minidips link input signals across consecutive channels to use the same input signal.

Technical Specifications

4.1 Protection Systems

PCMTM - Power Control Management

The RAM Audio PCMTM (Power Control Management) system allows sharing the amplifier's total power among the 4 channels based on user needs, with the capability to achieve high maximum power in a single channel. This system permits one channel to utilize more than 1/4 of the total power without bridging channels, which is highly beneficial for bi-amp systems requiring high power for subwoofers while less power is needed for satellites.

ICL2™ - Intelligent Clip Limiter

The RAM Audio ICL2™ is an anticlip system designed to prevent speaker failure and provide more acceptable sound quality, even when clipping occurs. The ICL2™ system preserves the music's 'punch' while keeping speakers under control.

4.2 Options

GPIO (General Purpose Input/Output)

GPI Control:

• +V: +15V output.
• POWER: Turn-on by contact (joining +V to POWER) or by voltage (3V-24V).
• MUTE: Mute by contact (joining +V to MUTE) or by voltage (3V-24V) referred to GND pin.
• GND: Ground Connection.

GPO (General Purpose Output): There are 3 contacts per channel to monitor the amplifier's state.

• Normal Operation: Pins 2-3 are closed (1-2 open) - OK Status.
• Non-Operative (Fault or OFF): Pins 1-2 are closed (2-3 open) - FAULT Status.

DANTE™ Inputs

DANTE™ inputs are provided via 2 independent RJ45 connectors, supporting primary/secondary redundancy.

AES67 Standalone Inputs

AES67 digital audio inputs are available via 2 EtherCon connectors, shared with Ethernet Control.

4.3 Data

Protections: Soft-start, Turn-on/Turn-off transients, Muting at turn-on, Over-heating, DC, RF, Short-circuit, Open or mismatched loads, Overloaded power supply, ICL™, PCM™.

* IEC filtered pink noise signal (40Hz-5kHz, 12dB crest factor)