Contacta VLD1 Vehicle Hearing Loop Driver Instructions
Contacts has a policy of continuous product development, therefore small specification changes may not be reflected in this manual. Images, labels, packaging, accessories and product colours are subject to change without notice.
Product Overview
The Contacts VLD1 is a compact two output Audio Frequency Hearing Loop Driver for use on passenger vehicles.
It is designed to improve communication with all passengers through improved speech intelligibility and signal to noise ratio.
The driver uses advanced class D amplifiers and integrated switching power supply offering maximum efficiency. The power supply is capable operating from a vehicle power supply of 24V.
The audio subsystem is built around an advanced DSP core, this combined with microprocessor control ensures optimal performance.
Note: For large area hearing loop installation instructions, consult the Large Area Hearing Loop Installation Guide.
Safety Instructions
- Read and keep these instructions.
- Heed all warnings.
- Follow all instructions.
- Do not use this apparatus near water.
- Clean only with dry cloth.
- Install in accordance with the manufacturer’s instructions.
- Do not install near any heat source.
- Follow information for polarized connections.
- Protect the power connections from being damaged/pinched.
- Only use attachments/accessories specified by the manufacturer.
- Refer to all qualified service personnel. Servicing is required when the apparatus has been damaged in any way, such as, liquid has been spilled or, the apparatus has been exposed to rain or moisture, does not operate normally, or has been dropped.
Power Sources – This product should be operated only from the type of power source indicated on the marking label.
Damage Requiring Service – The equipment should be serviced by qualified service personnel when:
a. Liquid has spilled into the equipment, or
b. The equipment has been exposed to rain, or
c. The equipment does not appear to operate normally or exhibits a marked change in performance, or
d. The equipment has been dropped or the enclosure damaged CAUTION REGARDING PLACEMENT: To maintain proper ventilation, be sure to leave a space around the unit (from the largest outer dimensions including projections) that is equal to or greater than these measurements:
Left and Right Panels (from edge of brackets): 0.5cm
Rear Panel (with connectors): 10cm
Top Panel: 1.46cm
Brackets for affixing this unit are pre-attached to the driver – these should be used to secure the driver in the desired location. Fixings are not provided for securing the driver in its end location.
Components
- VELD 1 Audio Frequency Induction Loop Amplifiers (brackets pre-fixed)
- User Manual
- 2x IL-SN01 Label
- M6 Bolt
- M6 Serrated Washer
- 2x 6 Pin Connectors
- 3x 2 Pin Connectors
- 4 Pin Connector
- Connector Tool
Related Document: VLD1 Software User Guide, available in the Resources section of the Contacts Systems Ltd website: www.contacta.co.uk/resources
Cable & Equipment: A length of loop cable determined by the loop design is also required. Hearing loop drivers also require ancillary equipment for audio feeds, such as a microphone or sound system.
Connections
- Earthing Point
- DC Power Input
- USB Input
- Audio Inputs – B1, B2, A
- Line Out and SPDIF Input
- Enables and Status
- Loop Outputs
Earthing Point
A location is provided for earthing the product to the vehicle; this is not a safety earth, but is required for EMC performance. An M6 bolt and serrated washer are included within the kit for this purpose.
DC Power Input
The driver is designed to operate on nominal supplies of 24V, but will operate over the range 9.5V to 35.5V.
The DC input has the following protections:
A) Reverse polarity protection – the unit will not power up under this condition.
B) Transient voltage – protected to +/-40% (7.6V – 49.5V)
C) Under voltage protection – the unit will not power up under this condition and will automatically recover when input reaches an in-range voltage.
| Input Voltage Nominal | 24V |
| Min/Max | (9V to 36V) |
| Current Typical | 0.5A |
| Max @ 24V | 3A |
| Connector Type | Wago 769 |
| Mating half P/N | 769-102_021-000 |
| Cable Type | 1.5mm CSA to 4mm CSA |
USB Input
This allows connection to a PC in order to access the setup GUI. Refer to the “Software and Setup Guide” for more information.
| Connector Type | USB Type B |
Audio Inputs – B1, B2, A
All adjustments for the audio inputs are made via the Contacts VLD1 GUI, accessed by connecting a PC to the USB connection.
Input B1
This input is transformer isolated. It is designed to be used as a line level input. Adjustments are made from the GUI.
Input B2
This input is transformer isolated and is designed to accept voltages from 1Vrms up to 100Vrms (line audio). This allows direct connection to speaker systems. Input adjustments are made from the GUI.
Input A
This input is not electrically isolated and is designed to be used primarily as a microphone input – it can also accept line level inputs.
To use it as a microphone input, a 5V phantom power is available; this is delectable from the GUI
| Pin No | Pin Description | |
| B1 | 6 | High Level Audio in (Hot) |
| 5 | High Level Audio in (Cold) | |
| B2 | 4 | Line Level Audio in (Cold) |
| 3 | Line Level Audio in (Hot) | |
| A | 2 | Line/Mic in (Hot) |
| 1 | Line/Mic in (GND) |
| Voltage | Current | Frequency | Notes | |||
| Nominal | Max/Min | Max | Typical | |||
| B1 | – | 100Vrms-1Vrms | 3mA | <1mA | 100Hz -5000Hz | Transformer Isolated |
| B2 | 1Vrms (0dBV) | 2Vrms-0.01Vrms | 2mArms | 0.5mArms | 100Hz -5000Hz | Transformer Isolated |
| A | 1Vrms (0dBV) | 2Vrms-0.01Vrms | 2mArms | 0.5mArms | 100Hz -5000Hz | Phantom Power (5V) |
| Connector Type | Mating half P/N | Cable Type | |
| B1 | Wago 769 | 769-106_021-000 | Twisted Pair1 twist/ Inch (25.4mm) |
| B2 | Wago 769 | 769-106_021-000 | Twisted Pair1 twist/ Inch (25.4mm) |
| A | Wago 769 | 769-106_021-000 | Twisted Pair1 twist/ Inch (25.4mm) |
Line Output and SPIFF Input
Line Output –
SPIFF – Sony/Philips Digital Interface
This interface is an optional feature which allows connection to equipment with an electrical digital audio output and offers greater noise immunity. Input adjustments are made from the GUI.
| Pin No | Pin Description | |
| Line Out | 4 | Audio Line Out (Cold) |
| 3 | Audio Line Out (Hot) | |
| SPIFF | 2 | RX |
| 1 | Digital Return |
| Voltage | Current | Frequency | Notes | |||
| Nominal | Max/Min | Max | Typical | |||
| Line Out | 1Vrms (0dBV) | 2Vrms-0.01Vrms | 2mArms | 0.5mArms | 100Hz-5000Hz | Feeds extra systems |
| SPDIF | 0.5V – 0.6Vpk-pk | – | – | – | – | – |
| Connector Type | Mating half P/N | Cable Type | |
| Line Out | Wago 769 | 769-104_021-000 | Twisted Pair1 twist/ Inch (25.4mm) |
| SPDIF | Wago 769 | 769-104_021-000 | Twisted Pair /Coax |
Line Output and SPDIF Input
Line Output –
SPDIF – Sony/Philips Digital Interface
This interface is an optional feature which allows connection to equipment with an electrical digital audio output and offers greater noise immunity. Input adjustments are made from the GUI.
| Pin No | Pin Description | |
| RTN | 6 | Enable Return |
| EN1 | 5 | Enable 1 |
| EN2 | 4 | Enable 2 |
| N/O | 3 | Status (Normally Open Relay Contact) |
| Common | 2 | Status (Common Relay Contact) |
| N/C | 1 | Status (Normally Closed Relay Contact) |
| Voltage | Current | Notes | ||||
| Pin No | Nominal | Max/Min | Max | Typical | ||
| RTN | 6 | – | 0V | 1.2mA | – | – |
| EN1 | 5 | – | 24V DC | 1.2mA | – | Enable Input |
| EN2 | 4 | – | 24V DC | 1.2mA | – | Enable Input |
| N/O | 3 | – | 24VDC | 5A | – | Volt-less Relay Contacts |
| Common | 2 | – | 24VDC | 5A | – | |
| N/C | 1 | – | 24VDC | 5A | – | |
| Connector Type | Mating half P/N | |
| RTN | Wago 769 | 769-106_021-000 |
| EN1 | ||
| EN2 | ||
| N/O | ||
| Common | ||
| N/C |
Enables and Status
Status
The status output consists of a pair of relay contacts sharing a common pole.
One pair is normally open, and the other is normally closed. These can be connected to external circuits or systems.
Should the VLD1 detect a fault the relay will operate. This will open the normally closed contacts and close the normally open contacts.
For a detailed list of conditions that will cause the status relay to operate, see LED Indicators on page 13.
Enables EN1 and EN2
These inputs can be configured in the GUI to perform various operations such as muting inputs or enabling low power mode.
For details on how to configure the enable please refer to the “Transport Driver Software and Setup Guide”.
| Pin No | Pin Description | |
| RTN | 6 | Enable Return |
| EN1 | 5 | Enable 1 |
| EN2 | 4 | Enable 2 |
| N/O | 3 | Status (Normally Open Relay Contact) |
| Common | 2 | Status (Common Relay Contact) |
| N/C | 1 | Status (Normally Closed Relay Contact) |
| Voltage | Current | Notes | ||||
| Pin No | Nominal | Max/Min | Max | Typical | ||
| RTN | 6 | – | 0V | 1.2mA | – | – |
| EN1 | 5 | – | 24V DC | 1.2mA | – | Enable Input |
| EN2 | 4 | – | 24V DC | 1.2mA | – | Enable Input |
| N/O | 3 | – | 24VDC | 5A | – | Volt-less Relay Contacts |
| Common | 2 | – | 24VDC | 5A | – | |
| N/C | 1 | – | 24VDC | 5A | – | |
| Connector Type | Mating half P/N | |
| RTN | Wago 769 | 769-106_021-000 |
| EN1 | ||
| EN2 | ||
| N/O | ||
| Common | ||
| N/C |
Loop Output(s)
The loop outputs are configurable from the GUI and can be used in parallel, phased or separate.
Loop drive level is also adjustable from the GUI.
These outputs are bridged tied meaning that each pin is floating and must not be connected to ground.
| Pin No | Pin Description | |
| Loop A & B | 1 | Loop – |
| 2 | Loop + |
| Voltage | Current | Notes | ||||
| Pin No | Nominal | Min/Max | Max | Typical | ||
| Loop A & B | 1 | – | 6Vrms | 5Arms | 1.25Arms | Floating O/P (Do not ground) |
| 2 | – | 6Vrms | 5Arms | 1.25Arms | Floating O/P (Do not ground) | |
| Connector Type | Mating Half P/N | Cable Type | |
| Loop A & B | Wago 769 | 769-102_021-000 | Twisted Pair (1.5mm CSA min) 1 twist / inch (25.4mm) |
LED Indicators
- Power – Illuminated when the power to the VLD1 is present and within the correct voltage range.
- Input A – Illuminated when there is a signal present at input A. The pre-amp gain must be set correctly.
- Input B – Illuminated when there is a signal present at input B. Thepre-amp gain must be set correctly.
- Output A – Illuminated when output A is driving current into its loop load. Will not indicate if the loop is disconnected.
- Output B – Illuminated when output A is driving current into its loop load. Will not indicate if the loop is disconnected.
Standards
- 2012/19-EU – The Waste Electrical & Electronic Equipment Directive
- 2015/863/EU – The Restriction of Hazardous Substances Directive
- EMC: EN/ECE R10 (EMC for vehicle components)
Specifications
Physical Data
| Dimensions | Height – 143mm (5.62”)Width – 294mm (115.7”) [361mm (14.2”) inc. brackets] Depth – 41mm (16.1”) |
| Construction | Intent / Mixed |
| Finish | Powder Coated |
Technical Data
| Audio Inputs | 1 x Line level Input (balanced and transformer isolated) | Voltage | -45dBV – 0dBV (optimised for -10dBV – 0dBV) |
| Frequency Range | 100Hz-6000Hz | ||
| Topology | Balanced and transformer isolated | ||
| 1 x Line High Voltage Level Input (balanced and transformer Isolated) | Voltage | +5dBV – +45dBV (0.562Vrms -100Vrms) | |
| Frequency Range | 100Hz-6000Hz | ||
| Topology | Balanced and transformer isolated | ||
| 1 x Universal Line or Microphone Input (microphone bias: optimised for Contacts microphones) | Voltage | -45dBV – 0dBV (optimised for -10dBV – 0dBV) | |
| Frequency Range | 100Hz-9kHz | ||
| Topology | Electronically Balanced | ||
| Microphone Bias | Optimised for Contacts microphones | ||
| [Optional extra feature, not fitted on standard units]1 x Digital Audio Input | Connection | SPIFF | |
| Encoding | PCM 16 bit | ||
| Sample Rate | 44.1KHz, 48KHz, 96KHz | ||
| Outputs | 2 x Independent Loop Outputs (delectable 0° and 90° phase shift) | Voltage | >12Vrms |
| Current | >4Arms | ||
| Electable 0° and 90° phase shift | |||
| 1 x Line Level Output | The line outputs should have the following characteristics: | ||
| Format | Audio mix of all drivers | ||
| Phase shift | 0° | ||
| Gain | 0dB | ||
| System Connections | 1 x Power Connection | Voltage | Nominal 24V (9V-24V) |
| Current | Maximum 6.6Arms @ 9VDC | ||
| Connector | WAGO 769 series detachable 2-wayblock | ||
| 1 x USB Connection [for factory configuration and system setup, adjustments and updates] | The input should have the following characteristics: | ||
| Connector | USB Type A | ||
| Use | Firmware/Config/Update | ||
| 2 x Enable/Disable(Mute) Connections | The input should have the following characteristics | ||
| Trigger | Configurable (High-Low or Low-High) | ||
| Threshold | Production Configurable (Resistor change) | ||
| Connector Type | WAGO 769 series | ||
Troubleshooting
| Symptom | Possible Fault | Action |
| The driver does not turn on. |
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| Interference (buzzing/ whistling/hissing) is heard through induction loop. |
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| The driver is excessively hot to touch. |
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| The loop output level indicates current is flowing but I hear nothing in the loop. |
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| The sound is distorted. |
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| The Clipping Status Lights are lit. | The connected hearing loop is too long. |
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Please contact your distributor (or Contacts if appropriate) if you are experiencing technical difficulties with the product.
UK & ROW
+44 (0) 1732 223900
sales@contacta.co.uk
www.contactainc.com
US & Canada
+1 616 392 3400
info@contactainc.com
www.contacta.co.uk
Documents / Resources
 | Contacta VLD1 Vehicle Hearing Loop Driver [pdf] Instructions VLD1 Vehicle Hearing Loop Driver, VLD1, Vehicle Hearing Loop Driver, Hearing Loop Driver, Loop Driver, Driver |
 | contacta VLD1 Vehicle Hearing Loop Driver [pdf] User Guide VLD1 Vehicle Hearing Loop Driver, VLD1, Vehicle Hearing Loop Driver, Hearing Loop Driver, Loop Driver, Driver |
 | contacta VLD1 Vehicle Hearing Loop Driver [pdf] User Guide VLD1, VLD1 Vehicle Hearing Loop Driver, Vehicle Hearing Loop Driver, Hearing Loop Driver, Loop Driver |
