A quick and easy DCC install (lots of pictures)

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HO & O (3-rail) trainman
One of the things I'm doing right now while I'm redesigning the layout is to improve my rolling stock and locomotives. I have a few Dash 9s and AC4400s, even though my era and location doesn't really have them. I had a couple of these large Athearn GE locomotives upgraded to have sound and ditch lights, so I figured I would do some installs. This project will not include ditch lights at this time.

Tools needed:

You can do the install without a good soldering station, but I don't recommend it. The Tsunami decoder requires a lot of constant power to run well, and so when I have the shell off, and I might as well remove the potential for shorts or bad electrical connections.

Phillips screwdriver (for coupler boxes)
small needle nose pliers
sprue cutters
hobby knife
small files
rosin core solder

paste flux (optional, but makes the job easier)
eye protection (I don't model railroad without it)
TSU-GN1000 FDL16 sound decoder
roll of 30 gauge wire or equivalent
small speaker

Kapton tape (this stuff is about $20 a roll, but it is very good for this stuff because it has better heat resistance and electrical insulation properties than regular electrical tape has...get a roll of this and it'll last you for years)

Athearn RTR locomotive (I'm a sucker for speed lettering)
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HO & O (3-rail) trainman
Part two:

Use the screwdriver to remove the coupler boxes and separate the shell from the frame. I find that if you keep your locos in boxes (or keep the boxes they came in), the plastic inserts make a nice and somewhat steady way to hold the locomotives without danger of breaking some of the fine details.

Originally, I had a TCS T1 decoder installed to the Athearn board. You won't need the board here since the Tsunami replaces it. The plastic clips that hold the wires on the board pickups can be removed and thrown out if you will solder. If not, you'll need to keep them when you reattach the wires to the Tsunami.

Everything (except the motor - lead) has been removed. The positive motor lead (the one center of the board without the plastic clip) does not have a wire because a small copper clip is riveted on the light board. To complete the connection, you will need to solder some of that 30 gauge wire.

Here is what the soldered wire looks like. The paste flux helps the wire stick better when you solder it.

While you're here, go ahead and tin your wires (all the wires going to the new decoder).

Note the "silver" tips.


HO & O (3-rail) trainman

Here is the Tsunami with both front and back track pickup leads attached, and the motor leads attached. I came from underneath and through the holes of the connection tabs because the decoder will be installed above the motor, and it's easier to keep the wires and decoder going the right way when you remove the shell.

I picked the GN-Genesis version of the Tsunami for a couple of reasons. First, it can use the factory installed Athearn 1.5v lights on the same connection tabs the light board uses (the two inboard ones, front and back), so wiring from loco to loco is more consistent. Also, unlike the AT version, there is no external capacitor to glue down somewhere else inside the shell.


HO & O (3-rail) trainman
The speaker:

One of the things I've learned about installing sound is that a good speaker with a good enclosure/baffle with good placement is a primary key to good sound. With the size of the GE loco here, there are a few places for installing a speaker, round or oval, but I prefer this speaker for most installs because 1) it sounds good 2) it's already enclosed and wired and 3) the size is good enough for this job and other installs. I've got ones in Athearn an SD40 and SD45, and also a CF7. I posted the back of the speaker so that people know where to get them if they want to try. This company also makes other speakers with baffles (I've got something else in a GP38-2).

Since I picked this speaker, I've already picked the placement. I usually like to install the speaker where the actual prime mover will be (or as close to it as possible), and that usually means on the long hood, below the radiators). This loco's radiator snaps out of the top, and is a great place for this exact speaker except it has a piece of plastic (stiffener) that is too high. That's where the hobby knife, files, and sprue cutters come into play.

You'll note the wires that go to the backup lights go by here. I recommend keeping them above the speaker. If not, they will be fairly close to the driveshaft on the rear truck, and may get wrapped around it. I went ahead and cut a notch in the plastic for the wires to sit.

The width of the speaker will keep it in place in the shell. The wires are held into place between the speaker and the shell in that notch.

Speaker installed.

Speaker installed with wires in the notch.

Edit: I went with the diaphragm/speaker up, instead of down, because the sound, to me, is a little better. If you generally aim your diaphragms up, you will be less likely to accidentally puncture it when you have to service the loco. Also, you can use the radiator or plastic shell to do a little reverb so that your sound can be a little fuller.
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HO & O (3-rail) trainman
All wires attached:

Since I have the space, I'm putting the decoder where the old light board was. I've wired it up so that when the shell is removed, the components that reside in the shell (the speaker and lights) stay with the shell. That's why the speaker wire was soldered from the top down.

At this time you may want to set the loco on the track with the shell off to make sure lights work, the motor works, and the sound comes on. You can program later. The starting address will be "03".

The Kapton tape here holds the decoder down over the motor. I put a piece of Kapton tape over the top of the motor (that copper strip you soldered the motor + lead to) to insulate it from the bottom of the decoder. IMPORTANT: You don't want the metal traces on the decoder to come into contact with the motor! If this loco was a Genesis loco, then the holes in the decoder would clip to the top of the motor.

Another note:

The two round barrels on the back bottom of the Tsunami GN version are capacitors, and if you mount this decoder on top of the motor as I have, you need to make sure the flywheel DOES NOT come into contact with the capacitors. Verify that you have airspace between the capacitors and flywheel.


HO & O (3-rail) trainman
Well, that's it. It takes me not quite an hour to take apart, install, test, program, and reassemble the locomotive with the sound, although the task isn't a race. The GEs are great because there is minimal fitting and guessing and testing to get the sound in, and such is where most of the time consuming (and sometimes frustration) comes in.

If you locate the decoder anywhere else in this or another locomotive (other than above the motor), you'll likely need more wire to give you enough slack for your track pickup leads.


Active Member
Thanks for this detailed DCC install Trey!!

I sure I wish you posted this a month ago, when I tried attempting a tsunami install on my Athearn F59-PHI Amtrak loco, in which I fried the decoder, and then I had to send it to Ulrich Models for the DCC/Sound install in which I am still waiting to receive back from them. They charged me $50.

What about the issue of the Athearn RTR's frying decoders because of some issue with how they ground the motors? I was told you have to do something about this when installing a decoder?

With your detailed instructions, I think I will try it again when I get another Athearn RTR loco.




Just make sure that the metal parts of the motor does not come into contact with the frame, and you won't have any grounding issues.

Can you post a video or an audio file of the sound coming out of the locomotive? I have the same locomotive, and the same speaker. I've been reluctant to install a tsunami in GEs because the sound isn't deep enough, I've never thought about putting the speaker under the grill plate (which I didn't know was removable)


HO & O (3-rail) trainman
Sure, I'll get a video together sometime.

A new shop opened up, and the guy there (another DCC fellow that I listen to) installed the QSI Revolution decoder in his AC4400 with the same speaker, and I'll admit that the sound was better. Unfortunately, the QSI was $35 more than the Soundtraxx one. Since I don't run these GE units often, I couldn't justify the greater expense this time.

The issue with Athearns is that on the DCC ready ones (with the light board installed), the motor is already isolated from the frame. As diburning said, just make sure metal parts of the motor come into contact with the frame.


The problem is that although the motor is supposed to be isolated from the frame, sometimes they do a sloppy job and the motor isn't completely isolated. When running on DC, this doesn't cause a problem, but when a decoder is installed, it may fry the decoder.

Another this is that the frame does not pass any electric current. Unlike the older models, the frame is not part of the electrical pickup system. HOwever, if you have loose or uncovered wires touching the frame, it can cause a short or if the engine is coupled to another engine with a similar setup.


HO & O (3-rail) trainman
That's good to know.

I've only installed sound in locomotives that have run for a while and already been set up for and run on DCC. I'll add a step in the future where I pull the motor out and make sure the bottom is well clear/insulated.


Active Member

Ya I'm not sure if that's what fried the decoder or not, who knows my wiring might have been good.

After that though, I was too scared to attempt it again.

BTW, I should be getting back my Amtrak F59-PHI soon, I just heard back from Steve at Ulrich. They also installed LED's for me, which was another $50, so the total install came to $100.

Nice write up


This is a very good write up and detailed enough so that anyone could install this type of decoder. Noice install of the speaker, glad you like them.

Jeff Smith
RailMaster Hobbies


New Member
SoundTraxx GN1000

I've installed the TSU-GN1000 in two of my Athearn Genesis F7's. I am really happy with them. The initial install was lots of trial and trial, but all in all I'm happy. I'll post pictures shortly. My one question is, I noticed two RED led's on the decoder itself. One looks like power (has a lightning bolt near it) but the other I'm not sure of. It has a triangle and an exclamation point in it. My exclamation point LED is lit when I'm in FORWARD or when I go from Forward to brake. It is NOT lit when I'm in reverse. I don't want to burn these up. Both of mine show the same.

Any ideas?

scott, Virginia Beach, Va


Noodle is good
mine light up too, i wouldnt bother much, but if at any moment the front headlight start flashing, count the number of time it flash and refer to the manual, some athearn motors draw more current that what the decoder can provide and can kill the decoder. Installing a better quality engine fix the problem.

BTW I installed the same speaker in the same spot in my c44-9w but i had to remove the two screw support on the baffle. 3 month after i havent still figured if i should dig a hole in the exhaust to allow the sound to exit there. Im stuck at the instalation of the ditch light, got no idea at all of what to do and where to put the wires

Edit : the light is for indicating that the locomotive is responding to the forward command
http://www.soundtraxx.com/manuals/Users Guide Diesel.pdf
go to page 57
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As I thought, it still isn't deep enough to my liking (although I highly doubt that it is possible to reproduce genuine GE chugging in HO scale due to the laws of physics)

The Tsunami also doesn't have the modern GE compressor sound. (I think they actually recorded it from a B30-7)


Yes, but QSI also doesn't sound realistic.

The custom Ulrich Loksound decoder hits the nail on the head. It has a deep enough prime mover sound that is more realistic than the QSI (but not as realistic as the tsunami) and has the modern GE compressor sound. The regular version has the early bell, and the P42 version has the modern GE bell (although it's labeled as P42, it does not actually sound like a P42 running HEP)


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