ART HeadAmp 6 Pro

Important Safety Instructions – Read First

Warning: This symbol indicates the presence of uninsulated dangerous voltage inside the enclosure, which may be sufficient to constitute a risk of electric shock.

Note: This symbol indicates important operating and maintenance instructions in the accompanying literature. Please read the manual.

Retain these safety and operating instructions for future reference. Heed all warnings printed here and on the equipment. Follow the operating instructions printed in this user guide.

Do Not Open:

There are no user-serviceable parts inside. Refer any service work to qualified technical personnel only.

Power Sources:

Only connect the unit to mains power of the type marked on the rear panel. The power source must provide a good ground connection.

Power Cord:

Use the power cord with sealed mains plug appropriate for your local mains supply as provided with the equipment. If the provided plug does not fit your outlet, consult your service agent. Route the power cord so that it is not likely to be walked on, stretched, or pinched by items placed upon or against it.

Grounding:

Do not defeat the grounding and polarization means of the power cord plug. Do not remove or tamper with the ground connection on the power cord.

Ventilation:

Do not obstruct the ventilation slots or position the unit where the air required for ventilation is impeded. If the unit is to be operated in a rack, case, or other furniture, ensure that it is constructed to allow adequate ventilation.

Moisture:

To reduce the risk of fire or electrical shock, do not expose the unit to rain, moisture, or use in damp or wet conditions. Do not place a container of liquid on it, which may spill into any openings.

Heat:

Do not locate the unit in a place close to excessive heat or direct sunlight, as this could be a fire hazard. Locate the unit away from any equipment that produces heat, such as power supplies, power amplifiers, and heaters.

Environment:

Protect from excessive dirt, dust, heat, and vibration when operating and storing. Avoid tobacco ash, drink spillage, and smoke, especially that associated with smoke machines.

Handling:

To prevent damage to the controls and cosmetics, avoid rough handling and excessive vibration. Protect the controls from damage during transit. Use adequate padding if you need to ship the unit. To avoid injury to yourself or damage to the equipment, take care when lifting, moving, or carrying the unit.

Servicing:

Switch off the equipment and unplug the power cord immediately if it is exposed to moisture, spilled liquid, objects fallen into openings, or if the power cord or plug becomes damaged during a lightning storm or if smoke odor or noise is noted. Refer servicing to qualified technical personnel only.

Installation:

Install the unit in accordance with the instructions printed in the user guide.

Introduction

The ART HeadAmp 6 Pro is a six-channel stereo headphone amplifier that includes a six-channel auxiliary input section. This section can be used to provide the popular "More-Me" function on each headphone mix. Each output channel also features a dual-function BALANCE control, which can pan between the LEFT & RIGHT sides of the main signal bus, or vary the MIX between the main signal bus and the AUXILIARY input for that respective channel.

Bass and treble controls are included on each output channel for fine-tuning the tone. Outputs include both front and rear panel stereo 1/4-inch TRS jacks for ease of installation and quick patching capability. Two MONO select buttons on each channel allow selection between four operating modes: 1) Stereo, 2) Mono Left, 3) Mono Right, 4) Mono Both (Left & Right) for versatile monitoring solutions.

Input options include XLR and 1/4-inch TRS balanced inputs with matching "Thru" jacks for bridging multiple HeadAmp 6 Pro units. An additional front panel stereo 1/4-inch TRS jack for quick patch override of the rear panel inputs is included for quick insertion of any stereo source. Eight-segment LED level indicators provide visual feedback of the signal level on all channels as well as the main signal bus.

Installation

The HeadAmp 6 Pro may be used in a wide variety of applications and environments. Its rack-mountable steel and aluminum enclosure is both attractive and designed for continuous professional use. Mounting location is not critical. However, for greater performance reliability, it is recommended not to place the unit on top of power amps or other sources of extreme heat, or strong magnetic fields.

AC Power Hookup

The HeadAmp 6 Pro has an internal power supply. Only connect the unit to mains power of the type marked on the rear panel. The power source must provide a good ground connection, and the ground pin on the mains plug should never be defeated.

Analog Audio Connections

Audio connections to and from the HeadAmp 6 Pro are:

Rear Balanced Inputs and Outputs:

• [XLR]: Pin 2 = Pos(+), Pin 3 = Neg (-), Pin 1 = Ground
• [1/4-inch]: Tip = Pos (+), Ring = Neg (-), Sleeve = Ground

Rear Stereo Aux 1/4-inch Inputs:

• Tip = Left, Ring = Right, Sleeve = Ground

Front Direct 1/4-inch Input:

• Tip = Left, Ring = Right, Sleeve = Ground

Front and Rear Stereo Headphone 1/4-inch Outputs:

• Tip = Left, Ring = Right, Sleeve = Ground

Controls and Jacks

Front Panel

Description of Front Panel Layout (Refer to Figure 1): The front panel features individual channel controls and master controls. Each channel typically includes controls for MONO L, MONO R, VOLUME (Level), BASS, TREBLE, and BALANCE. There are also CLIP indicators for each channel. The master section includes a MASTER VOLUME control with an associated eight-segment LED level meter, and a DIRECT IN jack. There is also a POWER switch.

• Direct In Jack: A 1/4-inch TRS jack providing a stereo unbalanced input that overrides rear panel balanced inputs. Useful for temporarily inserting a different main input signal or making an unbalanced connection.
• Master Volume Control: Adjusts the level of the main signal bus. The audio level is displayed by an eight-segment LED level meter.
• Mono L and Mono R Switches: These switches set the stereo headphone outputs to one of four operating modes:
  1. Both Switches Out = Stereo
  2. Mono L In & Mono R Out = Mono Left Channel Only
  3. Mono R In & Mono L Out = Mono Right Channel Only
  4. Mono L In & Mono R In = Mono Left & Right Channels Together
• Out Jack: A stereo TRS 1/4-inch jack providing a connection for each of the six output channels to stereo headphones or additional headphone distribution amplifiers. A second identical output jack is provided on the rear panel for each channel.
• Bass Control: Boosts or cuts low frequencies for each channel. Flat response at the 12 o'clock position.
• Treble Control: Boosts or cuts high frequencies for each channel. Flat response at the 12 o'clock position.
• Balance Control:
  • With no plug in the rear STEREO AUX INPUT: Varies the Left/Right balance of the main signal bus.
  • With a plug in the rear STEREO AUX INPUT: Varies the mix between the main signal bus and the STEREO AUX INPUT for that channel. This allows for a "More Me" mix.
• Level Control: Adjusts the audio output level for each channel, displayed by an eight-segment LED level meter.
• Power Switch: Rocker switch to turn the AC power On and Off. An LED indicator illuminates when the power is on.

Rear Panel

Description of Rear Panel Inputs (Refer to Figure 2): The rear panel features balanced input and thru connectors.

• Balanced Main Inputs: XLR and 1/4-inch TRS jacks for line-level signals. Gain sensitivity is identical for both types. The front panel DIRECT IN jack overrides these inputs.
• Balanced Main Thru: XLR and 1/4-inch TRS jacks hardwired in parallel with the BALANCED MAIN INPUT jacks. Useful for daisy-chaining multiple HeadAmp 6 Pro units.

Description of Rear Panel Outputs and Aux Inputs (Refer to Figure 3): The rear panel also provides headphone outputs and auxiliary inputs.

• Stereo Headphone Outputs: Stereo TRS jacks for each of the six output channels. Wired in parallel with front panel outputs. Can be used to drive headphones or feed additional headphone amplifiers. Optimized for 32-600 Ohm impedances. Avoid impedances lower than 16 Ohms to prevent clipping.
• Stereo Aux Inputs: Stereo TRS jacks for inserting a direct stereo signal into an individual headphone channel. When used, the BALANCE control for that channel becomes a mix control between the AUX INPUT signal and the main signal bus.

HeadAmp 6 Pro Operation

To begin operation:

1. Set the MASTER VOLUME and LEVEL controls on all channels fully counter-clockwise.
2. Set BASS, TREBLE, and BALANCE controls to their 12 o'clock positions.
3. Set all mono switches to their "OUT" position.

Connecting Audio Sources:

• Connect the rear panel BALANCED MAIN INPUTS to the audio monitor signal source using appropriate balanced or unbalanced cables. Unbalanced cables can be used but may introduce more noise.
• Alternatively, connect the audio signal source to the front panel DIRECT IN jack using a stereo TRS 1/4-inch plug.

Daisy-Chaining Units:

If connecting more than one HeadAmp 6 Pro to the same audio monitor signal source, daisy-chain the units by connecting from the BALANCED MAIN THRU connectors of the first unit to the BALANCED MAIN INPUT connectors of the next unit. Note: Daisy chaining only works with the rear panel connectors; the front panel DIRECT IN jack feeds only its respective unit.

Connecting Headphones and Amplifiers:

Connect headphones or leads to additional headphone amps (like the ART HeadAmp 4) to either the front or rear panel HEADPHONE OUTPUT jacks using stereo 1/4-inch TRS plugs.

Using the Auxiliary Mixer Function ("More Me"):

• Connect stereo signals to be mixed into individual output channels to the appropriate rear panel STEREO AUX INPUT jacks using a stereo 1/4-inch TRS plug. For mono signals, use a TRS plug with Tip and Ring tied together, or use the front panel MONO buttons.
• The AUX INPUT signal is heard only in that individual channel, controlled by the BALANCE and LEVEL controls for that channel.

Setting Master Volume:

Turn on the POWER switch. With the audio monitor signal active, increase the MASTER VOLUME control until the MASTER LED bar-graph level indicator lights the green and yellow LEDs, but avoids lighting the RED CLIP LED on loud passages. This ensures a strong signal for the channel amplifiers, allowing for lower gain settings (LEVEL control) and optimizing the signal-to-noise ratio.

Setting Channel Levels and Tone:

• Set the LEVEL control on each channel to a comfortable listening level.
• Set the BASS, TREBLE, and BALANCE controls to listening preference.

"More Me" Phase Consideration: When using the Auxiliary Mixer to add a signal like a direct vocal for a "More Me" effect, the relative phase of the AUX INPUT signal is crucial. If the signals are in phase, they sum, enhancing the desired signal. If they are 180 degrees out of phase (antiphase), the AUX INPUT signal will subtract from the main signal bus in that channel's headphones. Many consoles and preamps have a phase invert switch to set the desired mode.

Applications

Headphone Distribution System (Refer to Figure 4)

The HeadAmp 6 Pro is ideal for distributing audio signals to multiple listeners. A typical setup involves connecting the main stereo monitor mix from a mixing console to the BALANCED MAIN INPUTS of one or more HeadAmp 6 Pro units. These units can then feed headphones for individual musicians or monitoring stations. Multiple units can be daisy-chained for larger systems.

"More Me" Foldback System (Refer to Figure 5)

The "More Me" function allows individual musicians to mix their own signal (e.g., their vocal or instrument) into their headphone mix. This is achieved by sending a separate mix (e.g., vocal mic feed) to the STEREO AUX INPUT of a specific channel on the HeadAmp 6 Pro. The musician can then use the BALANCE control on that channel to adjust the level of their personal mix relative to the main monitor mix.

Example Scenarios:

• Large Scale Distribution: Connect a mixing console's main stereo output to multiple ART HeadAmp 6 units to provide headphone monitoring for an entire band or audience.
• Personalized Monitoring: A lead vocalist can receive the main mix plus their vocal feed via the AUX input, allowing them to adjust their vocal level ("More Me") in their headphones for optimal performance. Similarly, a drummer might receive a click track via an AUX input.

Warranty Information

Limited Warranty:

Applied Research and Technology (ART) warrants this product and its components to the original purchaser to be free from defects in workmanship and materials for a period of three years from the date of purchase. ART will, without charge, repair or replace, at its option, defective product or component parts upon prepaid delivery to the factory service department or an authorized service center, accompanied by proof of purchase date in the form of a valid sales receipt.

Exclusions:

• This warranty does not apply in the event of misuse or abuse of the product or as a result of unauthorized alterations or repairs.
• This warranty is void if the serial number is altered, defaced, or removed.
• ART reserves the right to make changes in design or make additions to or improvements upon this product without any obligation to install the same on products previously manufactured.
• ART shall not be liable for any consequential damages, including without limitation damages resulting from loss of use. Some states do not allow limitations of incidental or consequential damages, so the above limitation or exclusion may not apply to you. This warranty gives you specific rights, and you may have other rights which vary from state to state.

For units purchased outside the United States, an authorized distributor of Applied Research and Technology will provide service.

Service

If your unit requires service, please follow these steps:

1. Troubleshooting: Ensure the unit has power, all cables are connected correctly, and the cables are in working condition. Consult your dealer for assistance in troubleshooting or testing your configuration.
2. Contact ART: If you believe the ART unit is at fault, visit www.artproaudio.com. You may contact Customer Service for more assistance or directly request a Return Authorization (RA) for service in the "resources" area of the website.
3. Returning for Service: Pack the unit in its original carton or a reasonable substitute. The original packaging may not be suitable as a shipping carton, so consider using an additional box for shipping. Print the RA number clearly on the outside of the shipping box.
4. Include Information: With your unit, include a note with the RA number and your contact information, including a daytime phone number, preferably attached to the top of the unit.

For Your Reference:

• Date of purchase: ___________________
• Purchased from: ___________________
• Serial number: ___________________

HeadAmp 6 Pro Specifications

ART maintains a policy of constant product improvement. ART reserves the right to make changes in design or make additions to or improvements upon this product without any obligation to install the same on products previously manufactured. Therefore, specifications are subject to change without notice.