Using SMPTE with a General Audio Source

You can use a general audio source such as an MP3 player, laptop, smart device, etc... to both play audio and send SMPTE to the 18R2 to fire and control the show timing.

The instructions in this section use COBRA Show Creator to add SMPTE to a defined audio channel within your soundtrack and to add the proper script arguments. There are other methods used to layer SMPTE into your show audio using 3rd party audio editing programs such as Audacity. You can also reference our script format and example scripts for defining the SMPTE time code argument in your script.


Using SMPTE with a General Audio Source

Step 1: Set your show firmware version 5.1 or higher

When using COBRA SMPTE, your equipment must be on firmware version 5.1 or higher. To learn more about firmware, see Firmware User Guide.

If you are using COBRA Show Creator, you can select the firmware version from the Create New Show screen.


If you have an existing show, you can select the firmware version from the Show Settings menu option.


Step 2: Add or create a new audio file

Use the Audio Studio window to add new MP3 audio files or create a combined audio file that allows you to combine multiple single audio files into a single audio file without using a 3rd party audio editing software.

When creating a new show, select the Yes option to launch the audio file management window.


To add audio to an existing show, click the MP3 icon in the CSC lower-left corner.



From the Audio Studio, you can click Add New to add a single MP3 file or Create Combined file to combine multiple existing MP3 files into a single audio file without using a 3rd party audio editing software.

Step 3: Add SMPTE to the desired audio file left or right channel

From the Add SMPTE column, select Left or Right to automatically add SMPTE to the desired channel. While either channel is acceptable and has no difference, we recommend the Right channel to allow for consistency in our documentation and suggestions.


Upon selecting the desired channel, the SMPTE is added automatically to the desired channel in the background and a message appears when complete. The original left and right audio channels are converted to mono and added to the other channel. For example, if you chose Right then the original audio left and right is converted to mono and added to the Left channel. If you accidentally close the window or leave the screen, don't worry, everything will process normally in the background and you don't need to repeat the process.


While not covered in this user guide, you can also add SMPTE to your audio file using 3rd party software such as Audacity

Step 4: Select the designed audio file and choose the "Timecode 2" option 

Upon selecting an audio file for your show, the option to select a SMPTE timecode option will appear automatically if the timecode option is not already set on your show.


If you are editing your script directly after being created from Excel, Finale3D, or another 3rd party choreography software, you can add "timecode1" or "timecode2" to column J in your script file.

Step 5: Export your show to the 18R2 using a USB thumb drive  

To export your show to the 18R2, click Export from the left-side main menu. Download the cobra.csv file and save to your USB thumb drive. We recommend the COBRA certified USB drive.

Place the USB drive into your 18R2 while powered off. Then, power on your 18R2. Once booted up, the 18R2 will load the script and briefly display all green LEDs to indicate success. Any issues will display as error codes. Once loaded, cue LEDs will display red for any cue / channel combinations that are expecting continuity. This is normal and indicates your script loaded successfully.

Well done. Your show is now configured for SMPTE. Let's proceed to fire your show using the SMPTE Player.

Step 6: Export your MP3 File

To export your MP3 file, click Export from the left-side menu. Download the MP3 file which will include SMPTE as selected in step 4. Prepare and save this MP3 to play through your sound system such as an MP3 player, laptop, or smart device, etc...

Step 7: Connect your 18R2 to the right (red) channel and your sound system to the left (white) channel

The RCA audio cable has two outputs including a right (red) output and a left (white) output. Connect the red output to the 18r2 and the white output to your sound system. Upon playing your show, the SMPTE is sent into the 18R2 through the right channel and the audio soundtrack is sent into the sound system through the left channel.

Step 8: Power on your 18R2 and test your SMPTE audio output

Power on your 18R2. By default, the 18R2 goes into TEST mode after startup. From your sound system, press the downloaded MP3 file.

Upon successfully receiving SMPTE, the 18R2 will display a value of tc0 to tc9 where tc9 is the highest quality timecode and tc0 is the poorest quality timecode. We also suggest testing your audio sound system to ensure you have high-quality audio at the desired volume.

Step 9: Fire your show

To start your show, press the trigger button and trigger channel set on your show. If you are not sure what this is, goto Show Settings > Trigger Channel & Trigger Button.


If you created your show using Excel, Finale3D or another choreography software, see script format to determine your current trigger channel and trigger button.

Once you start the show on the 18R2, "PAU" will display on the three 7-segment displays on the 18R2. You can now begin playing audio from your general audio source to start the show. If you pause, resume, or stop, the 18R2 will follow along. You can also choose a defined play position to start your show mid-show.

If you encounter an issue with your audio, the script can still be started while the 18R2 is displaying "PAU" by pressing the ARM button. 

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