ART SyncGen User's Manual

Important Safety Instructions

[Caution: Risk of Electric Shock - Do Not Open]

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[Information: Refer to Manual]

This symbol indicates important operating and maintenance instructions in the accompanying literature.

General Safety Guidelines:

• Retain safety and operating instructions for future reference.
• Heed all warnings on the equipment and in this manual.
• Do not open the unit; refer servicing to qualified personnel.
• Connect only to the specified power source.
• Route power cords to prevent damage.
• Do not defeat grounding or polarization.
• Avoid moisture, damp conditions, and liquids.
• Keep away from excessive heat and direct sunlight.
• Protect from dirt, dust, vibration, and smoke.
• Handle with care to prevent damage during transit or operation.
• Unplug during lightning storms or if smoke/odor is detected.
• Install according to manual instructions.

Introduction

Thank you for purchasing the ART SyncGen. This device enhances digital recording systems by providing a stable time-base reference, improving flexibility and reliability.

Device Overview: The ART SyncGen is a compact digital audio device. Its front panel features a large digital display showing the sample rate (e.g., '192'), several BNC output connectors (OUT 1, OUT 2, OUT 3, OUT 4), two S/PDIF coaxial outputs, and indicator LEDs for termination status. It also includes a 'Sample Rate' button and labels for BNC output termination and sample rates (192K, 176K, 96.0K, 88.2K, 48.0K, 44.1K). A termination key is provided: LED Off = no termination, Red LED = too low/shorted, Green LED = 75 Ohm termination.

The SyncGen allows synchronization of digital audio equipment via BNC Wordclock or S/PDIF inputs, centralizing timing and reducing accumulated errors in digital recording chains. It also monitors BNC wordclock cable and termination status. A green indicator signifies correct termination, while red indicates a short or over-termination. An unlit LED means the output is unconnected or unterminated.

Changing the Sample Rate

Pressing the front panel 'Sample Rate' button cycles through six master clock rates. The numeric display shows the current frequency for BNC wordclock and S/PDIF outputs. The SyncGen remembers the last setting upon power-up.

For complete setup, you may need to adjust the sample rate in your recording software and, for some hardware, manually set the device's sample rate via its driver or control panel.

Hooking up the SyncGen

The setup involves two steps:

1. Connect each audio device's wordclock or S/PDIF input to the SyncGen.
2. Terminate each connection if required.

S/PDIF outputs are internally terminated and do not have termination LEDs. For BNC wordclock outputs:

If the termination LED lights green, the device has internal termination, and you are done. If the LED is off, termination is needed. Add a 75 Ohm terminator at the end of the cable run, or use a BNC "T" adaptor (e.g., RadioShack model #278-112) if a 'Wordclock Thru' input is not available.

A red LED indicates an output-loading problem (output too low). Try removing the terminator. If the issue persists, the output or cable may be shorted.

The SyncGen features discrete 75 Ohm output drivers protected from shorts and over-voltage.

Termination and Why It Is Needed

A terminator is a resistor connected between the signal and ground at the cable's end. It reduces signal reflections from the undriven end, which can cause timing errors, especially on longer cable runs.

A green termination LED confirms correct termination. A red LED typically indicates too many terminators or a cable short, often occurring when a 75 Ohm terminator is added to a device with internal termination.

To check for internal termination, connect the SyncGen to a device and observe the termination LED. A green light confirms internal termination.

The SyncGen can also function as a BNC wordclock cable tester. Connect a cable; unlit LEDs indicate no short. Add a 75 Ohm terminator with a BNC "T" adaptor; a green LED indicates a good connection.

S/PDIF Outputs

Two coaxial S/PDIF outputs are provided for synchronizing digital audio devices lacking BNC wordclock inputs. Devices like the Digidesign Digi 002 can use these S/PDIF inputs as a timing reference. The SyncGen's S/PDIF output sends "digital black" (all audio bits set to zero) for a stable locking source.

Wordclock Interconnect Configurations

Diagram 1 illustrates various wordclock interconnect configurations. It shows scenarios for terminated devices, unterminated devices with and without 75 Ohm terminator plugs, and connections to the next unit. These configurations demonstrate options using 'Wordclock Thru' jacks or BNC "T" adaptors for proper signal termination.

Connecting More Than One Device to an Output

Multiple digital audio units can be connected to a single wordclock output via daisy-chaining using 'Wordclock Thru' jacks or BNC "T" adaptors. ART products with 'Wordclock Thru' are not internally terminated, facilitating daisy-chaining. A 75 Ohm terminator is required on the last unit in the chain.

Note: Devices with internal termination should always be placed at the end of the cable run. Avoid using a BNC "T" adaptor on such units, as it effectively adds an extra termination.

Cable Length

High-quality cables introduce a delay of approximately one nanosecond per foot. For optimal performance, it is recommended to keep cable lengths under 15 feet between devices connected to the same SyncGen output. This minimizes timing discrepancies, representing about half a bit interval at 192KHz.

Jitter

Jitter is the variation in sample rate timing. Imagine trying to read a second hand on a shaking watch; this imprecision is analogous to signal error. Digital systems process millions of samples per second, making precise timing critical. Both recording and playback jitter can cause audible errors. Jitter introduced during recording is permanent and difficult to correct, making the SyncGen a valuable tool for maintaining timing accuracy.

Warranty Information

Limited Warranty

Applied Research and Technology (ART) warrants this product and its components against defects in workmanship and materials for one year from the date of purchase. ART will repair or replace defective units at no charge upon prepaid delivery to their factory service department or an authorized service center, accompanied by proof of purchase.

Exclusions

This warranty does not cover misuse, abuse, or unauthorized alterations/repairs. It is void if the serial number is altered or removed. ART reserves the right to make design changes without obligation to apply them to previously manufactured products. ART is not liable for consequential damages. Some states may not allow limitations on incidental or consequential damages.

For units purchased outside the United States, service is provided by an authorized ART distributor.

Service

If your unit requires service:

1. Verify the unit is the cause of the problem. Check power, connections, and cable integrity. Consult your dealer for assistance.
2. If the ART unit is at fault, visit www.artproaudio.com to contact Customer Service or request a Return Authorization (RA) in the 'resources' section.
3. Pack the unit in its original or suitable packaging, preferably within another box for shipping. Clearly print the RA number on the outside of the shipping box.
4. Include a note with the RA number and your contact information (including a daytime phone number) with the unit.

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 same on products previously manufactured. Therefore, specifications are subject to change without notice.

Applied Research & Technology

Website: www.artproaudio.com

Email: cserve@artproaudio.com

Model: SyncGen SG-5004-101