FURMAN HDS-16 (01) PDF Document

The FURMAN HDS-16 system is a headphone and audio distribution product designed for studio and live stage monitoring. The HDS-16 distribution device accepts eight mono and four stereo inputs from a mixing console and routes them, along with DC power, to one or more HRM-16 remote mixers via a 50-pin Centronics cable. The HRM-16 is a 16-channel mixer with a powerful headphone amplifier and a built-in talkback system.

A single FURMAN HDS-16 can drive a maximum of eight HRM-16 remote mixers. Since each HRM-16 has two headphone outputs, this allows up to sixteen musicians to be supplied with eight different headphone mixes from one HDS-16 unit.

The HRM-16 is a 16-channel mixer with a headphone amplifier. Its features include:

• Local effects send and return

• Line out (mono)

• Bass (LO) and treble (HI) shelving EQ controls with 12 dB boost and cut

• Talkback level and master volume controls

• A built-in microphone and talkback system

The FURMAN HDS-16 system features two talkback modes for communication between musicians and the mix engineer:

1. Live/Stage Mode (Default): This mode allows the HDS-16 to communicate with all HRM-16s. Musicians using an HRM-16 can communicate back to the HDS-16, but not with other HRM-16 users. This mode is useful for live situations and helps eliminate feedback from adjacent stage monitors.

2. Studio Mode: This mode establishes communication among all HRM-16s and the HDS-16, much like an intercom system. Any user pressing their TALK button can speak to all other users. This is useful for discussion between musicians and the engineer between takes.

To change the talkback mode, you need to move a jumper inside the FURMAN HDS-16 unit. The default setting is Live/Stage Mode (J-2).

Step 1. Use a Phillips screwdriver to unscrew the middle two screws located near the top of the front panel and all screws on the top of the unit.

Step 2. Remove the top cover. You will see the main PCB.

Step 3. Locate the jumpers J-1 and J-2 in the left-front corner of the PCB. Lift the jumper from the J-2 two-pin header (default Live/Stage mode) and move it to J-1 to change to Studio mode.

The SOLO feature allows the mix engineer to let musicians hear a rough mix, final mix, or soloed tracks from the mixing console without the musicians needing to change their HRM-16 level settings.

To use this feature, the mix console’s main or mix output must be patched to the FURMAN HDS-16’s channel D input. When the SOLO button on the HDS-16 front panel is depressed (or activated via a remote switch), all HRM-16 sends are muted except for the channel D stereo and talkback outputs. The SOLO ON LED will light when the function is active.

After using the SOLO feature to listen to the main console mix, it is important to turn the channel D level control to 0 (off) on all HRM-16s before resuming recording. If you forget to turn down channel D, the main console mix will be present along with the intended channel mix in the headphones.

The front panel of the FURMAN HDS-16 serves as a patch bay for all input connections. It includes eight mono inputs and four stereo inputs, with both 1/4-inch and TT input connectors for each channel. All connectors are balanced and use the Tip/Ring/Sleeve (TRS) wiring convention. It is important to note that if both connector types are used for the same channel, the TT connector will be active and the 1/4-inch connector will be disabled.

Connect the mix console’s line-level talkback-microphone output or cue send to the FURMAN HDS-16’s 1/4-inch TALKBACK INPUT jack located on the far left of the front panel. This signal is then distributed to all connected HRM-16s. To monitor talkback coming from the HRM-16s, use the RETURN FROM HRM-16 connector.

The rear panel of the FURMAN HDS-16 features:

• Six 50-pin Centronics output connectors labeled “TO HRM-16 UNITS” for connecting the HRM-16 remote mixers.

• An AC power input connector and an ON/OFF power switch.

• A GROUND lift switch.

The GROUND lift switch on the rear panel of the FURMAN HDS-16 has two positions to help eliminate hum or noise:

• LIFT: In this position, the signal ground is separate from the chassis ground. The earth ground from the AC line cord remains connected to the chassis only.

• GROUNDED: This is the default position where signal ground is connected to chassis ground. Use this setting unless there is hum or noise present.

The top panel of the HRM-16 remote mixer provides the following controls:

• Level controls for four STEREO SOURCES (A, B, C, D).

• For each of the eight mono channels: an EFFECTS SEND control, an L/R pan control, and a level control.

• A MASTER volume control.

• HI and LO shelving EQ controls.

• A TALKBACK VOLUME control, TALK button, and a built-in microphone.

• An EFFECTS RETURN level control.

To use the talkback feature, press the TALK button on the HRM-16’s top panel and speak in the direction of the built-in microphone, which is indicated by three small holes in a triangle shape above the button. The microphone can pick up voices from up to six feet away. The level of incoming talkback from the main console can be adjusted using the TALKBACK VOLUME control.

HRM-16s can be connected to a FURMAN HDS-16 in two ways, with a maximum of four HRM-16s connected in series from a single HDS-16 output:

• Parallel: Each HRM-16 is connected directly to one of the six Centronics outputs on the rear of the HDS-16. This is also known as a star configuration.

• Series: One HRM-16 is connected directly to the HDS-16. Additional HRM-16s are then connected sequentially to each other in a daisy chain using their “OUTPUT TO ADDITIONAL HRM-16’s” and “INPUT FROM HDS-16” connectors.

The HRM-16 rear panel features several 1/4-inch TRS connectors:

• EFFECTS SEND: Connect this mono output to an effects processor.

• EFFECTS RETURN: Use the L input for a mono effects return (panned center) or both L and R inputs for stereo effects.

• LINE OUT: This mono, line-level output can be used to route the HRM-16’s mix to a monitor system. Its signal is affected by the MASTER VOLUME and HI/LO EQ controls.

• TALKBACK SWITCH REMOTE: Plug a momentary switch into this jack to activate the talkback function remotely, either instead of or in addition to the top panel TALK button.

The maximum recommended cable run for the 50-pin Centronics cable connecting an HRM-16 to a FURMAN HDS-16 is 200 feet. For cable runs beyond 100 feet, there will be some power loss.

The following table details the power loss per 100 feet of Centronics cable for different headphone impedances:

The system has several protection circuits:

• HRM-16: The headphone driver and power supply regulators are protected against over-temperature and current overloads. The power delivered from the HDS-16 is protected by PolySwitch resettable fuses inside each HRM-16, which prevent a defective unit from affecting others.

• FURMAN HDS-16: The regulated power delivered to the HRM-16s is protected against shorted cables by an over-current crowbar circuit, which turns off the affected power supply. The AC-line is protected by a 1-Amp Slo-Blo fuse.

If the over-current protection circuit in the FURMAN HDS-16 is triggered (e.g., by a shorted cable), the affected power supply will turn off. To restore normal operation, you must first remove the defective cable or HRM-16 causing the fault, and then turn off the power to the HDS-16 for at least 30 seconds before turning it back on.

INPUTS: Balanced, 50 kΩ, 90 dB CMRR

INPUT IMPEDANCE: 50 kΩ

LINE OUTPUTS: Balanced or single ended, 50 Ω, 68 dB OCMR

SINGLE CHANNEL GAIN: 21 dB; +4 dBu for maximum output

REMOTE SWITCH: Connect tip to ring to mute all outputs except channel D (solo function)

SIZE: 3.5″ H x 19.0″ W x 8.0″ D

WEIGHT: 9.4 lb (4.27 kg)

LINE OUTPUTS: Balanced or single ended, 50 Ω, 68 dB OCMR

POWER OUTPUT: 750 mW at 32 Ω, 770 mW at 100 Ω, 260 mW at 600 Ω

REMOTE SWITCH: Connect tip to ring to activate the talkback microphone

SIZE: 2.9″ H x 11.0″ W x 7.0″ D

WEIGHT: 3.5 lb (1.59 kg)

DISTORTION AND NOISE: < 0.002% THD+Noise, 20 Hz – 20 kHz at full rated power

DYNAMIC RANGE: > 105 dB

FREQUENCY RESPONSE: +0/-1 dB 13 Hz – 32 kHz

POWER REQUIREMENTS: HDS-16: 120 VAC, 60 Hz, 82 W; HDS-16E: 230 VAC, 50 Hz, 82 W

CROSSTALK: < -95 dB at 10 kHz