Installing the decoder was straightforward, as its color-coded wiring harness conforms to National Model Railroad Association Recommended Practice 9.1.1. Its size, .25″ x .68″ x 1.68″, allowed it to sit right down on top of the motor in a Stewart HO scale F3 after I’d removed the model’s original printed-circuit board. I cut away part of the locomotive’s chassis to allow a 1″-diameter speaker in a shallow enclosure to ride above the rear truck facing up inside the body.
The speaker I used is Sound-Traxx no. 810054 with a no. 810010 circular enclosure or “baffle” – neither is included. Many other 8-ohm speakers and enclosures will perform as well. The largest speaker and enclosure combination that you can fit in a given model is usually the best choice in terms of sound reproduction.
Programming. Those who have used the earlier steam Tsunami decoders know that these are sophisticated controllers and sound generators with many features and even more programming options. The diesel Tsunami sounded good as soon as I powered up the track under my F3, but I had to put in a few hours of study and testing to learn what this decoder can do.
The decoder is packaged with a sheet listing its specifications and giving basic instructions for installation and operation. To take full advantage of its features, however, you’ll want to download the Tsunami user manuals from the SoundTraxx Web site. If you want to print them and place them in a binder as I did, make sure the paper tray is full before you start!
The 17-page “Quick Start Guide” and 33-page “Installation Guide” are especially helpful for those getting started in DCC, but the most detailed programming instructions are in the 65-page “Diesel Sound User’s Guide.” The 105-page “Technical Reference” spells out the meaning of every bit in every Tsunami Configuration Variable (CV). I did print it out but found most of what I wanted to know in the “User’s Guide.”
Capabilities. When configured the way I wanted it, the decoder made a locomotive that was already a good runner oily smooth at low speeds. With sufficient acceleration momentum and an exponential speed curve, you can hear the diesel engine revving up realistically before the unit begins to move. I also programmed a fair amount of deceleration delay for long gliding stops, but set the F11 brake squeal function to stop the locomotive more quickly for precise spotting.
This is indeed a combined sound and control effect, an electronic brake that’s one of my favorite features of the Tsunami. It works by subtracting a number entered in CV61 from the deceleration or braking rate set in CV4. The unit can coast smoothly for a long distance when the throttle is turned down or off, but you can still make controlled stops using a function button as a brake.
For DCC cabs with 10 or fewer functions, the User’s Guide gives detailed instructions for re-mapping F11 to another function control. I put it on F9.
Other features. The decoder’s selection of 16 prototypical air horn sounds included the Leslie A200 that’s correct for my as-built Santa Fe passenger F3. With the light configuration CVs I set the headlight for realistic non-directional, on-off-with-dimmer operation. If I’d needed them, functions are included for backup lights, simulating rotating signal lights, and blinking various types of flashers and beacons. Programming options accommodate bulbs or LEDs without requiring additional resistors.
For descending grades F4 engages the sound of a dynamic brake fan, and I programmed the decoder to realistically reduce the speed of the diesel engine when dynamics are used, independent of the locomotive’s speed. Mixer controls independently adjust the volume of every sound function, and there’s a CV for overall volume too. Equalization and reverb adjustments help maximize the performance of the speaker.
If you find the sound of idling units annoying while focused on something else, you can engage the decoder’s Quiet Mode. This automatically shuts off the audio after a time set by CV113, but the sounds restart whenever the decoder receives a non-zero speed command or a function command other than “mute” (F8).
The sounds you want. Our response to sound effects is necessarily subjective, and that argues for sound decoders that each of us can customize for our own enjoyment. With its many programming options and operational flexibility, the Tsunami diesel sound decoder has the potential to make your model diesels sound exactly the way you want.
Price: $119.95
Manufacturer
SoundTraxx
210 Rock Point Drive
Durango, CO 81301
www.soundtraxx.com
Features
16-bit digital sound system
14 diesel locomotive sound effects including a selection of programmable horns
Multiple lighting effects
14 functions
Advanced motor control including back-electromotive-force (BEMF) load compensation
Available with digital sound recordings for three Electro-Motive Division, three Alco, General Electric FDL-16, and Fairbanks-Morse H-12 diesel engines
1A capacity (steady-state current in Stewart F3 .11A; stall current .4A)
Supports programming track and operations mode programming
Supports DC (“analog mode”) operation with limited control of sound effects
