Linear Acoustic LA-5448 User Manual
  1. Manuals
  2. Brands
  3. Linear Acoustic Manuals
  4. Recording Equipment
  5. LA-5448
  6. User manual

Linear Acoustic LA-5448 User Manual

Ac-3 frame synchronizer and rate shaper
Hide thumbs
Table of Contents

Advertisement

Quick Links

Download this manual
Model LA-5448
AC-3 Frame Synchronizer and Rate Shaper
User's Guide

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the LA-5448 and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Related Manuals for Linear Acoustic LA-5448

Summary of Contents for Linear Acoustic LA-5448

  • Page 1 Model LA-5448 AC-3 Frame Synchronizer and Rate Shaper User’s Guide...

  • Page 3: User Guide

    Model LA-5448 AC-3 Frame Synchronizer and Rate Shaper User Guide Release Date: February, 2006 Software Version: 01.00.21 and later Linear Acoustic Inc. Phone: 888-292-3117 FAX: 717-735-3612 email: www.LinearAcoustic.com...

  • Page 4: Warranty Information

    Linear Acoustic be liable for incidental, special, direct, indirect or consequential damages, or loss of use, revenue or profit even if Linear Acoustic or its agents have been advised, orally or in writing, of the possibility of such damages.

  • Page 5: Table Of Contents

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Table of Contents List of Figures ............................vii Chapter 1: Introduction ........................5 Principles of Operation..................5 Location of LA-5448....................6 Future Updates......................6 Warranty and Feedback ..................7 Chapter 2: Connections ........................9 Unpacking and Inspection ..................9 Installation .......................9...
  • Page 6 Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide 5.1.3 Unit Produces 448 kbps Output, but it is Silent......21 Chapter 6: Specifications ......................23...

  • Page 7: List Of Figures

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide List of Figures LA-5448 Frame Synchronizer/Rate Shaper Block Diagram ............6 Rear Panel ............................10 LA-5448 processing three individual AC-3 streams, rate shaping disabled ......13 LA-5448 processing three separate streams, rate shaping enabled..........14...

  • Page 8: Chapter 1: Introduction

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Chapter 1: Introduction The Linear Acoustic LA-5448 AC-3 Frame Synchronizer and Rate Shaper accepts three independent AC-3 streams and synchronizes them to a reference signal applied to the fourth input. This fourth input will accept 48kHz AES signals containing PCM or AC-3.

  • Page 9: Location Of La-5448

    Figure 1-1 LA-5448 Frame Synchronizer/Rate Shaper Block Diagram Location of LA-5448 The Linear Acoustic LA-5448 Demultiplexer/Splicer is best located near network satellite receivers or just prior to a multiplexer. In some cases, it maybe located near AC-3 encoders such as a Dolby DP-569. As it will likely be in a transmission envi- ronment, dual redundant power supplies and hard relay bypass are provided for trou- ble free operation.

  • Page 10: Warranty And Feedback

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Introduction Warranty and Feedback Please take a moment to fill out the warranty card included with the unit and drop it in the mail. This will enable us to contact you if there are any software or docu- mentation issues.
  • Page 11 Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Introduction...

  • Page 12: Chapter 2: Connections

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Chapter 2: Connections This chapter covers all required connections for the LA-5448. Unpacking and Inspection Before unpacking the unit, inspect the outer carton for shipping damage. If the car- ton shows damage, inspect the unit in those areas. Please save the carefully designed shipping carton and packing materials.

  • Page 13: Rear Panel

    WARNING: Replace fuses only with the same type and rating 2.3.1 Connection Ports All of the LA-5448’s connections are on the rear panel and are described in detail below. See Chapter 5: Specifications for specific pinouts. Figure 2-1 Rear Panel •...

  • Page 14: Quick Setup Notes

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Connections Quick Setup Notes The LA-5448 requires only minimal setup to be up and running. • Apply power to BOTH IEC AC power inlet modules. • Note that once booted (~ 5 seconds), the front panel will display “No Refer- ence”...
  • Page 15 Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Connections...

  • Page 16: Chapter 3: Applications

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Chapter 3: Applications The LA-5448 is intended to be used in an emission (transmission) environment. This chapter shows several applications of the system as it is intended to be used. Of course other applications are possible: •...

  • Page 17: La-5448 Processing Three Separate Streams, Rate Shaping Enabled

    448 kbps output data rate. Also shown is a “crash switch” between two AC-3 sources that will be cleaned up and kept at a constant data rate by the LA-5448. This is useful for commercial insertion appli- cations.

  • Page 18: Dolby Digital) Notes

    AC-3 data packets are carried. It does not matter which selec- tion is chosen as long as the LA-5448 and the encoder match. The default for the LA- 5448 is Pro-32, the default for most known professional equipment that generates or passes AC-3.
  • Page 19 Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Applications...

  • Page 20: Chapter 4: Menus

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Chapter 4: Menus This chapter discusses how to use the front panel LED interface to access the menus. Most of it is rather obvious, and a bit of experimentation will quickly make you comfortable nav- igating through the submenus.
  • Page 21 Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Menus L in e a r A c o u s tic S ta tis tic s L A 5 4 4 8 S e tu p L A 5 4 4 8 V 0 1 .0 0 .2 1...

  • Page 22: Main Menu Level

    The Statistics menu provides more detailed information about the health of each of the input signals applied to the LA-5448. The main status LEDs on the front panel give the first indication of trouble when illuminated red, while further details about the error con- dition can be found under this menu.

  • Page 23: System Menu

    Silent frame mode is enabled by default and has the function of keeping a continuous AC-3 stream flowing from each output of the LA-5448 in case of input error or loss. If a corrupt AC-3 frame is detected, the last good frame is repeated, then silent frames equal to the data rate and channel mode (acmod) of this last good frame are output until valid error free AC-3 frames return.

  • Page 24: Chapter 5: Troubleshooting

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Chapter 5: Troubleshooting The Linear Acoustic LA-5448 is a very stable and reliable unit, and most problems can be traced back either to mis-wiring causing incorrect signals to be applied to the unit or more than likely to mis-configuration.
  • Page 25 Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Troubleshooting...
  • Page 26 Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Chapter 6: Specifications Table 6-1 Electrical Specifications Sampling Rate 48 kHz ( 0.1%) 1.5 AC-3 frames, +/- 0.5 frames (48 msec, +/- 16 msec) Output Delay minimum, can be increased in 32 msec steps to provide up to 4 seconds of delay to match external equipment.
  • Page 27 Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Specifications Table 6-2 Table 6-3 Mechanical Specifications Dimensions 1.75 24 in (4.45 48.3 61 cm) Net Weight 6 lb (12.6 kg) approx. Shipping Weight 8 lb (15.75 kg) approx. 115/220 VAC, auto ranging, 50–60 Hz,...
  • Page 28 Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Specifications RS485/422/232 Port 9-pin female D-connector with full-duplex RS-485 protocol running up to 115 kbps. Pi- nout is compatible with SMPTE 207M. Table 6-5 RS-485/422/232 Input Port Pinout Connection Shield TX A asynchronous data out –...

  • Page 29: Ethernet Port

    Linear Acoustic LA-5448 AC-3 Frame Synchronizer/Rate Shaper User Guide Specifications Ethernet Port The Ethernet port is a standard RJ-45 female connector that supports 10 or 100BASE-T. This connector is currently not active, but will be enabled in a future software release.

Table of Contents