Problems with Aftermarket Sound Installation : By Fred Krause

Bachmann EMD DDA40X Centennial DCC on board 

Guest Article By: Fred Krause

Recently, a customer purchased two of Bachmann’s EMD DDA40X Centennials with DCC on board.  It’s a beautiful model compared to older Bachmann locomotives and is quite detailed. The customer had asked us if we could install sound in the engines and as it said “designed for aftermarket sound installation we said yes.  

   The engine was advertised with the following features: 

• DCC-equipped for speed, direction and lighting.
• dual-mode NMRA decoder
• 2 skew-wound motors with 4 flywheels
• LED headlight (constant lighting)
• weathered air intakes and exhaust stacks
• scale 42" wheels with RP25 wheel contours
• designed for aftermarket sound installation
• E-Z Mate Mark II couplers

 

Remember one of the selling points is “designed for aftermarket sound installation” It Sounded easy enough.  WRONG!!  Statements like the one above can be misleading.  This is just a little of what we encountered add sound to this beautiful piece. 

Our electronics person, Norm Sutherland, does all of the DCC and sound boards installations for Structures and Trains. We took on the job to installation on the two DDA40X engines; and thought it should be an easy installation since the engines were sound ready according to Bachmann. We have done custom installations on older trains that were made long before DCC, and on trains that were never meant to have decoders in them. We have literally shoved ten pounds of decoder into a five pound area to put it lightly, so this was a welcome change for us. Not wanting to take anything for granted when it comes to installations so I decided to call Bachmann and ask what they recommended for the locomotives.

 

         Before calling Bachmann, I pulled the shell of the locomotive to see exactly what it looked like inside. Other than the area where the current decoder was placed, and the fuel tank area underneath the frame, there was absolutely no room inside the engine. The frame had two motors, one for each set of trucks, the flywheels, brass on the drive shaft end and two counter weight flywheels on the opposite end. On the top part of the frame, was a PC board, it was quite long, almost six inches and contained the usual resistors and capacitors. The PC board was mounted on the very top of the frame. It had an eight pin plug which was in use by the DCC module and solder joints clearly marked, for two speaker connections. Underneath the engine in the fuel tank it was setup for duel speakers, it had mounting areas for two 1 3/8” x 5/8” speakers. I knew from past experience that it was a common size.  

   I called Bachmann, and told them I wanted to put sound into two of the sound ready DDA40X locomotives that had recently come out. They told me to call Soundtraxx.  

   I called Soundtraxx and I was told that I would need two TSU-1000 sound decoders. The gentleman on the other end of the phone seemed not to care that I already had DCC in the machines. But I already have DCC control in the engine I told him. “We recommend model# 827102, this is for the DDA40X”. I also needed speakers; each locomotive will accept two speakers. I told him the speaker dimensions were 1 3/8” by 5/8” and was told part# 810113 was the correct size. He also added if I set up the reverb I may be able to get a dual engine sound. This sounded interesting to me so I took down the part and told him I would be in touch. After making a couple of more phone calls it looked like Tsunami was the best option I had. I checked a couple of other sound decoders and none of them seemed as good an option. After all of this, I thought, what is going on here, there is already a decoder in this and I have to install another decoder? This doesn’t sound like its ready to me. 

   The boards came in and I started to get the installation going. Right away there was a problem. The decoders would not fit in the space where the factory decoder was installed. I could see that this was going downhill fast and this was definitely not going to be an easy install after all. But we pride ourselves on giving the customer what he wants.

so I showed Fred our options. One, we go with one speaker and place the decoder in the tank, or we make a new space and mount it where the old Bachmann board was. Fred decided we should go with the dual speakers, and I have to admit that an opportunity to make a duel engine sound coming out the locomotive would be pretty neat.  

    I removed the old PC board and made a new mounting surface out of some non conducting G-10 fiberglass material. I had to machine off 1/8” of the motor mounting casting on both sides to get the decoder to fit in the height between the shell and the frame, it was a tight fit but it worked fine after machining. The factory board had all of the resistors needed for the lighting so I installed all the new resistors for the front, rear and strobe lights. One added bonus to this was the awesome extra lighting effects. The new strobe had a number of options, and it worked very well with the Tsunami. 
 
 

   Next I had to mount the speakers. I thought that this was going to be an easy task. Wrong again!! Dimensionally, the width and length the speakers were correct. But the radius in the corners of the speakers did not match the corners where they mounted on the fuel tank so I had to file them larger. I matched the two radius edges together and then found that the speakers were too thick to fit between the frame of the engine and a mounting in the space in the fuel tank!  
 

    I had to mill two pockets in the frame about 1/8” deep.  This was just deep enough to allow the speakers to fit and the frame and fuel tank to come together. Finally!! When I had finished I ended up doing quite a bit of modification to the engine for a speaker ready engine.  

   This was a new release from Bachmann with all the features that today’s Model Railroader is looking for. Detail and modern electronics adds realism to your layout. So as we stated in the beginning of this article few locomotive are as ready as you might think to receive a decoder much less a sound card.   

      Due to the ever changing evolution in the computer chip industry the decoder is becoming smaller and more robust; however there are still many problems to overcome. We have been able to purchase locomotives with sound installed by the manufacturers for a while now. Companies such as Broadway Limited Imports with the release of their Paragon II system, and Walther’s Proto 2000 Series are just a couple that have been doing this. Some of the new sound systems are quite amazing, who would have thought a few years ago that we would be seeing a small gage train running around our layouts with the realistic sound we are experiencing today. However, beware, there are still problems and some systems that claim “sound ready” can be misleading. 

      At Structures and Trains by Fred we have installed numerous DCC decoders in many different trains from N scale to O scale. We have found that many “DCC ready” and “Sound ready” trains are really not ready at all.  

       Four years ago I converted my N scale layout from a conventional DC layout to DCC and from that time on I was sold on the concept. DCC, it is a fantastic improvement over the old block layouts, hands down. In O scale, sound has been around for a many years.  Now we are starting to see realistic sound in HO Scale and N Scale; it’s becoming more common than ever.  I hope this will help you if you decide to add sound to this or another piece and what you might be facing regardless how DCC Friendly or Sound Ready the manufacturer declares.