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The Whistlestop

The Whistlestop

Newsletter of the

Great Northwestern Railway


Volume 2, Number 1                                                                                           February 27, 2007

                                                                                                               Update October 30, 2007

                                                                                                               Ugly formatting cleaned up May 14, 2008, with thanks to Glenn!


Neighbors Complain of NOISE…

The GNW Invests In Sound!


The railway now sounds like a railway!.


Major retrofit program upgrades old locomotives with sound decoders!


The Great Northwestern Railway has recently completed a year long program evaluating sound decoders in their locomotive fleet.  “Sho’ ‘nuf, I showed up yesderda, and hardly could believe ma ears: the engine house sounded like it were filled with engines,” remarked one of the engineers for the railway.


While some of the employees may be pining for more peaceful days, most of the operators on the railway are happy with the change.  “Hard to blow the horn for the grade crossing if ya don’t have a horn.”  Fatalities at the only road crossing in Warm Springs have dropped significantly over the past year; most attributable to the fact that motorists now can hear the train coming (and that the road is now finished).


There was some hesitation to embark on the program, owing to cost and the complexity of the equipment.  However GNW management is now convinced the decision was good.  “Just press F8 on the throttle and the whole train goes silent.  You tell me if that is how you would want to run,” as quoted from one of the hoggers.  “Even if management could have kept to the original idea of just having one engine on the line, it is worth the conversion.  Once you have sound, you’ll never go back!”




The engine that first received a sound decoder was SW-7 cow/calf 1012/1025.



Railway engineers have a different view.  “A lot of weekends were spend moving this program ahead,” stated the shop foreman.  “We had a committed crew work and rework several of the early engines.  It’s not just the electronics, it’s dealing with the physics of sound as well.”  The retrofit program pushed the shop to their limits, with goals of installing the sound, the lighting features, and keeping the custom painted engines looking good.


Whistlestop publishers were able to contact the railway, and they graciously provided a copy of the executive summary report on the program.  Overall, the information gained was very worthwhile, if not a bit expensive.  As a convenience to our readers, it is included in this special issue.



Sound Decoder Test Program


Decoder Comparison

Study Report


The program tested a variety of decoders installed in a variety of equipment.  With the exception of factory installed decoders, all of the speakers were installed with enclosures fabricated from plastic; no pre-made enclosures were used since often there was not enough room to install the speakers with them.


Program Summary:


Decoder Model Loco Manufacturer Loco Model Speaker Pros Cons
Soundtraxx DSD-100LC
1st Gen EMD Diesel
Athearn SW-7 calf TDS Small Oval Speaker Lower cost, VERY realistic engine sound, the bell is by far the most realistic I have heard; the horn sounds perfect and is very controllable. Since this was my first try at sound, I removed the power train from the calf and used only the sound and light outputs. In addition to getting power from the trucks, the calf is hard-wired to the cow for better power pickup.

Some complaints have been made against the 100LC 1st gen for the ‘transition’ sound. It takes a few seconds while the engine winds down, transitions, and revs back up as the throttle is run up. While prototypical, the fact is while the engine sounds transition, a model loco has probably traveled across most of the yard. If we had scale yards, it would not be an issue. Good or bad? Your call.

Most GNW equipment has a ‘rotating beacon’ flasher on the roof of the cab. The LC series of decoders only has head lights. Would be nice to have a 3rd output. Also, like most things DCC, it is very sensitive to losses of power. Even a short drop in voltage will have the ‘engine’ go to idle and then rev up. Also, it will ‘forget’ what functions are on (e.g., headlight, bell) until a function key is pressed and the decoder is refreshed. The only other issue is the newer sound decoders can produce more sounds. Once you hear all those new sounds, it is hard to go back!
Soundtraxx DSD-100LC -2nd Gen EMD Diesel Atlas GP40 TDS Mini Oval Speaker Lower cost, VERY realistic turbo added to an excellent engine sound, the bell is by far the most realistic, the horn sounds perfect and is very controllable. Same as above. Also, the old motor is not a good match for DCC. The back EMF tries as it might to make it run smooth, but it is very clunky at low speeds. Don’t waste the money on installing a new decoder in a 25 year old engine! One other comment: the ‘mini’ speaker has a characteristic ‘squeak’ or ‘chirp’ at the high end that just seems to accent an annoying portion of the sound from decoder. A well sealed enclosure minimizes or eliminates the sound, but anything short of that, and it is there.
MRC HO DCC "Brilliance" Diesel Sound Decoder Athearn GP38-2 TDS Small Oval Speaker Love the engine sound; full bodied and lots of detail. The random sounds are welcome and add a surprising amount of depth to the model. It is great to have it just idle in the yard! And the third lighting output allowed an LED to function as a rotating beacon. Can you say LOUD?! The 4 settings are either “Off”, “Loud”, “Too Loud” and “Way Too Loud.” No readback on function codes is a pain when trying to tweak the operation. Super obnoxious “startup” sound when turning the layout on cannot be overridden… and cannot be used when operating. The bell is extremely tinny, as is the horn. Cannot modify the programming for the random sounds. Speaker was too big for the engine, so I had to get an aftermarket. Will the GNW buy another MRC sound decoder? See below.
Soundtraxx Tsunami DSD-Medium Steam version Bachmann-Spectrum 2-8-0 Consolidation MRC Speaker from above. (Approx. 1” dia round speaker with enclosure) In a word: Wow! Incredible features and the ability to control almost every and any feature. Super realistic chuffs, changing based on load and throttle setting. Great random sounds. I could go on and on, but between the random sounds and the manually activated sounds, you could have a whole operating session without moving the engine! (For an extra treat, hit the ‘air release!) The bell is great. Even the occasional safety valve blowoff sounds good. And when running, the brake squeal, the rod clang, and even the coupling sounds are just great. In all, there are over 22 steam sound effects. Yowza!

(Steam on the GNW? Why yes, for those fan trips, of course!)

Of all things, my #1 complaint with this decoder is the whistle. They give you 8 choices, but the variation between the ‘short’ whistle sound and the ‘long’ whistle sound on any one selection is such that it makes most of them unusable to do a ‘long-long-short-long’ sequence (did they record them from the same engine???). That narrows the selection down to maybe 2 whistles, and both are, well, lukewarm. IMHO, the air pump sounds like a rock rattling in a can (the DSD-090-Steam is better); very disappointed in that one. The other big complaint I have is that the decoder will not put out a very low ‘minimum’ starting voltage. Even at setting “0” or “1” the engine just jumps up to 5-7 mph. Slightly better running it on 128 speed steps, but when starting out on 128 steps, the first couple of steps pulse the power, and the loco lurches at every pulse. It is frustrating on a decoder this nice!
Soundtraxx DSD-100LC-GE Diesel Athearn U28B TDS Small Oval Speaker Stepping back into a more successful decoder line, trying the distinctive GE sound in a classic Athearn riding on blomberg trucks. Great, distinctive GE sound, particularly the idle. The horn and bell are identical to the EMD units. Same comments as before. The only other comment I would add is for some reason the distinctive GE sound gets too quiet when running. Not sure if it is the old mechanism drowning out the sound, or if it is just quiet. Even at idle, it is quiet. I have messed with the enclosure, speaker, etc; just cannot get much sound out of it.
Soundtraxx DSD-100LC-1st Gen EMD Diesel Bachmann Spectrum P2K GP38-2 TDS Small Oval Speaker Enough with the retrofitting the old technology locos… tried something new. Bought the GP38-2 on clearance. Took a hack saw to the frame and weight to make some room for the decoder and speaker. Just love how it turned out. The loco runs smooth as silk; the sound is just right (the GP38 is not turbocharged, so the 1st generation sound is appropriate). Same comments as with any of the other DSD-100LC’s. Still, it is a good, solid, predictable decoder.
QSI ???? Bachmann Spectrum P2K SW8 Stock Tested a ‘pre-packaged’ decoder equipped loco. The features are INCREDIBLE! From the startup sound, to the compressor, just perfect! For all the glitz and ease of buying it all set up, it runs very poorly. Incredibly sensitive to any gap, even going over a turnout. Not enjoyable to run, particularly as a switcher, with low speeds being a perfect set-up for a stall at the worst place. And the sound of the prime mover…what is that all about?! Sounds more like a front loader…that gets louder but no RPM change when throttling up.
QSI ???? ATLAS MP15 Stock Tested a second ‘pre-packaged’ decoder equipped loco. VERY similar to the SW8 (is there any difference?). In contrast to the SW8, this runs like a champ. Smooth and silky, can run almost imperceptibly slow without a stall or visible cogging of the motor. And the sound is fantastic. The horn is probably the best of all decoders. Bell is great. Love the random effects. OK, so what is with QSI that seems to think a burble getting louder is supposed to represent an accelerating prime mover?! SAME sound as the SW8. No RPM changes. And the sound does not at all match a prototype sound, let alone an EMD 645 series engine. Anyone used the upgrade chip? Does it sound ANY better?
MRC ???? ATHEARN SD45-2 Stock My third try at a packaged sound-equipped engine (or engines in this case). One of the best sounding EMD turbo’s on the market, and includes all 8 notches. Reasonably good speed control. It takes some fiddling, but can set configuration variables to allow most functions to operate while in consist modes. I found selecting two different, but similar, horns programmed on both units created a wonderfully deep and complete sounding horn when in consist mode (which I plan to keep them in). Start up and shut down sounds are fantastic. Some of the air let-off effects are spectacular. Bells are not bad.

The model itself is very good, with crisp details, real micro bulb lights and a functioning beacon.

Can you say loud?! I finally got to the pot via the exhaust stack, but not before breaking one of the nice grille pieces. It is at an OK level now, but frustrating to get there. You cannot really adjust the volume with the shell off without a lot of disassembly/reassembly because the shell provides a lot of the sound enclosure. One of the units must have got some glue on the frame from the factory since I could NOT separate the shell. The units did not want to play well together at first; one tended to bind up. After running a while, it is much better, but nothing like the Atlas units. Brake squeal is very cheesy. As above, no readback possible.

Athearn/MRC seems to be getting there, but the standard is much higher from other manufacturers. They need to operate some of their own locos with ones from the competition so they know where they need to end up. My opinion, obviously!


A Digitrax sound decoder has been procured and is scheduled for installation into an Athearn SW-1500.  Machining of the frame and repowering will be required to make that installation complete. 


A couple additional installation notes.  As has been shared time and time again, the speaker is only half the equation.  The speaker enclosure is just as important.  The GNW found better sound coming out of a good enclosure with a mini speaker, than a shabby installation with the larger speaker.  The tender of the consolidation was big enough to hold the stock 1” MRC speaker and very solid enclosure, and the sound out of that is just fantastic.  As for wiring, the test program started using electrical tape to insulate the soldered electrical connections, but moved to small heat shrink tubing.  In the effort to save a few bucks, it made for messy installations.  The heat shrink tubing is easy to use, reliable, and makes for a much more compact installation, very critical when installing a sound decoder in a switcher!  Finally, with lights, perhaps a beacon, a speaker, the decoder and power wiring, preplanning the work is critical.  Work from the deepest part of the installation outward, testing each step on the way.  Many of the loco installs required at least 2, sometimes 3 enclosures to be built to work well for both running gear clearances and for good sound.  Patience is the key.  Even when forgetting to install that headlight bulb just as you finish installing the decoder. 


One thing about sound: At the end of the day, there is a great satisfaction in just kicking back and listening to the burble of a fleet idling in the yard.  Sorta brings back to some memories of just hangin’ out at the yard and just basking in the presence of that much horsepower.  Good stuff!





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