Sound Depot


Welcome to the Digitrax Sound Depot!

Digitrax SoundFX® decoders come "ready to run" with pre-loaded sounds appropriate for the locomotive each decoder was designed to fit.  Decoders not built for specific locos come preloaded with a dual scheme that gives the choice of a generic diesel or generic steam sound project. 

Using Digitrax SoundLoader and your PR3, you can change the sound projects your decoder plays. SoundLoader runs on your PC and connects to your sound decoder using the Digitrax PR3 programmer. With SoundLoader you can easily manage the sound project files your decoders use.

Downloading and Installing Sound Projects (.spj)

It's easy:

1. Find the sound project your want to download on SoundDepot.

2. Connect your PR3 programmer to the programming track on your layout.

3. Place your SoundFX decoder equipped locomotive on the programming track.

4. Open the SoundLoader application.

5. In the Sound Loader application, open the .spj file with the sound project you want to load into the decoder.

6. Click on "Program" and wait for the programming process to complete (usually 60-90 seconds).

7. That's it. You've just customized your locomotive.

Modifying Sound Project Files

You can customize any sound project using your own recordings.  You can change the horn or whistle to one that is available on the Sound Depot or one that you have recorded yourself. You can replace any locomotive sound segment (a chuff, or a brake squeal, etc) with an actual sound recording you've made. You do this with the SoundLoader utility in conjunction with a Digitrax PR3 programmer. Once you've customized the project, you can save the sound project (.spj) file with a new name.  This will let you use your custom project over and over again.

We encourage you to share your customized sound projects with other modelers by submitting them to the Sound Depot by clicking here. We are happy to post customer projects on the Sound Depot!  Please limit file sizes for upload to less than 20mb.

Creating New Sound Project Files From Your Own Recordings

If you're really motivated you can take .wav files you've recorded and make your own customized sound project files. This process of converting 'raw' sounds you've recorded in the field into a Sound Project file is a long and exacting task, especially if you want the sound to be realistic.  On the other hand it is very rewarding to hear the recordings you have made come from your models.  Sound editors are readily available on the web for free.  

There are two kinds of sounds in SoundFX decoders, simple sounds and sequenced sounds. A simple sound is a sound that always sounds the same and always has the same length. An example of a simple sound is a bell. The striker strikes the bell and it rings for a certain length of time.  The other type of sound SoundFX decoders support is sequenced sound. A sequenced sound is a sound that is made up of three parts: an Attack sound, a Sustain sound, and a Decay sound.  Examples of sequenced sounds are the whistle, water pump, horn, etc.

To prepare a simple sound, using a sound editor:

1. Isolate the sound by trimming the excess time from the recording by carefully marking the beginning and the end of the sound you want to create.

2. Save this trimmed file as a .wav file as "8 bit" and 11 kilohertz (khz).

3. Open the SoundLoader application. The main screen of SoundLoader shows "sound types" or parts of the locomotive's sound scheme (Diesel Bell, Diesel Brakes, etc).

4.  Locate the sound type you want to change in this list and "right-click" on that entry -

5.  Select "Assign Sound File" 

6.  Browse to the new Wav file you created and saved previously, select the file and click the 'Open' button.

7.  You've successfully modified the original Sound Project File.  Save this modified sound project file under a new file name.

You can repeat the above steps and replace as many (or all) of the sound types as desired in the original Project file. Once you've finished your customized Sound Project File you can download it directly to your locomotive using SoundLoader's "Program" button, email it to a friend who has a similar Locomotive, and submit it to the Sound Depot by clicking here to share it with other model railroaders on the Digitrax Sound Depot.

To prepare a sequenced sound, using a sound editor:

A sequenced sound is a sound that is made up of three parts: an Attack sound, a Sustain sound, and a Decay sound. The Attack is the ‘starting’ sound, the Sustain is the ‘running’ part of the sound, and the Decay is the 'end' sound. An example of a sequenced sound is the horn. Blowing the horn for 15 seconds requires an Attack sound that begins the sequence, a Sustain sound that prolongs the sound for as long as desired, and finally ends with a Decay sound. In actual practice, file sizes for the beginning and end of the sound, the Attack and Decay, may possibly be larger than the Sustain because the Sustain is simply a small snippet of sound repeated as long as needed.

Examples of SoundFX sequenced sounds are the Whistle, Water Pump and Horn. In the SoundLoader main screen you’ll see each of these sounds have a Start, Run, and End component. To prepare a sequenced sound you'll need to make 3 .wav files (The Start, Run, and End parts)

The finer points of making natural sounding sequenced sounds include:

1.  Recording several complete sound events (for example, several complete whistle blasts from start to finish).  If possible, make these recordings each time varying distance from the Locomotive. If you’re going out to a distant site to make the sound recordings, you might as well come back with more than one recording to choose from. A single recorded whistle blast may sound great by the siding, but may not sound as good once you listen to the recording at home so get several recordings from different distances and give yourself the latitude to choose the best.

2.  Once you’ve chosen the best candidate, again you’ll need to isolate the complete sound by trimming the excess time from the recording. The goal here is to get just the complete sound event (whistle/horn blast/etc) with almost no sound before or after on the recording. Once you’ve got it, save this file. Save a copy of it (with a different name) in a safe place on your hard drive. Next, we’ll chop up the working copy of this sound file.

3.  The ‘Start’ Part

Listen to your newly trimmed sound. Repeatedly. Depending on the sound editor you’re using, playing from the beginning you’ll eventually be able to ‘see’ a place on the timeline where the sound stabilizes. In other words, you’ll be able to see the point on the timeline where the tone of the sound starts to remain consistent. That’s the point where you want to make your first cut. Save this file segment (again, in the 8 bit / 11 kilohertz format). Be descriptive, if it’s a horn recording name it something easy for others to identify like:  Start_GMF7_horn.wav.

4.  The ‘Run’ Part

This one’s easy, depending on how long the total recording is, most of it will be the stable ‘run’ part of the sound. Copy a piece of this sound (typically less than 1 second long) to the clipboard and save this sound. Again, name it something consistent and descriptive: Run_GMF7_horn.wav.

5. The ‘End’ Part

By now you’ve probably got the hang of it. Mark the point in your recording just before the run sound starts to change, copy from this point to the very end of your sound clip. Save it naming it something like:  End_GMF7_horn.wav.

6.  You’re now ready to overlay these newly create sound components into an existing Sound Project file to create a new, unique project file. There’s no limit to what you can create.

7.  Congratulations! You’ve just created your very own locomotive sound.  Be sure you have everything saved.  And don't forget to submit it to Digitrax if you are willing to share with others.

SoundLoader Software

Using your PR3 programmer and SoundLoader Software, it’s quick and easy to download sound project files into your Digitrax FX decoders.

How to find a sound project for your locomotive

The Sound Depot is organized by locomotive with one or more sound projects available for each locomotive. Simply browse the list of locomotives for the one that is most like the model you are working with, then download one of the sound projects. Generic steam and diesel sounds are also available if you are not sure what to choose.

Click here to browse locomotives and sound projects

Sound Decoders

Digitrax offers a wide variety of Sound FX decoders to fit many different locomotives. You’ll need to have a Digitrax SFX decoder installed to take advantage of using .spj files.

Click here for Digitrax Sound FX decoders

Submit your Sound Projects

Use our submission form to submit your Sound Projects


Click here to submit your sound project