Could use some DCC Decoder change over help for sound

[darticus]

I have two N SCALE locos my wife got me for Xmas. One is a spectrum heavy mountain Rio Grande and one is a Spectrum Articulated 2-6-6-2 1397. She also got me two decoders to try. One decoder is a Tsunami TSU750 with a speaker and one is a digitrax sdn144s Soundfx with speaker. Both of the locos mentioned have DCC in them factory but I wanted sound. I need some advice as to which loco to try first, which would be the easiest switch over, and do I remove the original decoder or just add the new one. Hope someone will help that has performed the surgery before. Maybe a precedure would be real nice. Thanks Ron

[skipgear]

The mountain will be the easiest as the tender has more room in it. I would put the Tsunami in the Mountain, providing it's the right Tsunami (heavy steam I think has the right sounds). The H4 will be a bit more of a challenge, but because of the smaller vanderbilt tender, speaker placement may be a challenge.

In both cases you will need to remove the factory decoder, and possibly the factory light board from the tenders to make room. If need to remove the lightboard, then you will need to scavage the resistors from the lightboard to protect the headlight and backup lights.

[darticus]

Do you know how the Heavy Mountain tender comes apart? Ron

The mountain will be the easiest as the tender has more room in it. I would put the Tsunami in the Mountain, providing it's the right Tsunami (heavy steam I think has the right sounds). The H4 will be a bit more of a challenge, but because of the smaller vanderbilt tender, speaker placement may be a challenge.

In both cases you will need to remove the factory decoder, and possibly the factory light board from the tenders to make room. If need to remove the lightboard, then you will need to scavage the resistors from the lightboard to protect the headlight and backup lights.

[skipgear]

[darticus]

FANTASTIC! Got the coal part out. Have the body apart. So far so good. Ron

[skipgear]

As in the picture, remove the rear tender truck.

[darticus]

Have the board as in the pic. The Digitrax sdn144ps has a plug does this make it easier? The Tsunami heavy steam has just wires. Ron

[skipgear]

the plug on the SDN144 is for an NMRA 8 pin. Bachmann, and for that matter, most N doesn't use that plug. You have to cut the plug off for either install.

Open up your instructions for the loco and it shows how to install a decoder. First you must remove the factory decoder, then decide if you have enough room for everything as is, probably not. You need to include a baffle or enclosure for the speaker, the decoder, stay alive cap and any other wiring under the shell of the tender.

Here is a SDN144 crammed into a scratch built PRR tender. It is shorter than what you are dealing with but it also doesn't have the light board to contend with...



The lead box is the speaker enclosure.

[darticus]

Is the black thing with wires floating above the board the decoder and the board the light board? Wow! I thought I was gonna hook up Two wires to the wheels and Two wires to the speaker and use the factory decoder for the motor and all this would fit and done. Would I be better trying a Light Mountain that I have or same big job? I guess I'm choking as its my first change over.
After studying this thing it looks like I remove the factory decoder by desoldering the original decoder and solder in the new decoder which ever one I decide on and shove a speaker somewhere and wire it in. Does this sound right? Ron

[skipgear]

That's pretty much it. Just "Shoving a speaker" in the tender will lead to some pretty bad sound though.

[darticus]

What I did to try and test decoder sounds is hook a speaker to each decoder and run the red and black wires from the decoder to the proper rails. This should give me sound and than I can switch them and hear the difference. Does this sound ok to you? I gave it a try and the digitrax decoder is super low in volume. I can't hardly hear it.  CV 58 =CV 15. I programed the master volume to 15 but still very low. Any suggestions. 
I think I have to program the loco and this decoder with sound at the same time on the program track so they both get the same ID. Ron

That's pretty much it. Just "Shoving a speaker" in the tender will lead to some pretty bad sound though.

[skipgear]

I believe you are confused. Both sound decoders you say you have will control the motor and lighting also. There is no need to keep the factory decoders in the system. You remove the factory decoder and then install the sound decoder.

You won't be able to program the decoders until they are installed. The deocder needs a motor and or headlight load hooked up for the programing system to function. It needs the load so that the system knows that decoder got the signal. If not, it won't take.

Also, a loose speaker, no matter what the size and shape will sound terrible. Speakers need at minimum a baffle, preferably an enclosure to work right. Take it from somebody that did competition car stereo for a couple years, take your time and do it right. Just slaping it in there will not be worth the time and effort.

[darticus]

Me saying shoving a speaker in was just a funny way, I thought, of saying install a speaker properly.  I'm sure you have said to someone buying speakers, will just shove some great speakers in there and it will sound great, same thing.
I thought the speaker part was the easy part. Checking things out today I found the baffle makes a night and day difference with this. It almost triples the volume.
  What I was saying about connecting the decoder is that I wanted to just test the sound I would get from each decoder  before deciding on which decoder to install and I was able to do that. All I had to do it hook the speaker up to either decoder and connect the decoder red wire to the proper rail and the decoder black wire to the proper rail. Putting the controller on Loco 3 let me hear what each decoder sounded like ,even the scuff at speeds, without the train moving.
Now I have to get the nerve to remove the original decoder and wire this in. Do you cut the wires on the board or do you unsolder them? Do you remove the board to work on it? Is this the board you called the light board? Do you know the best way to remove the factory decoder? Thanks Again Ron

I believe you are confused. Both sound decoders you say you have will control the motor and lighting also. There is no need to keep the factory decoders in the system. You remove the factory decoder and then install the sound decoder.

You won't be able to program the decoders until they are installed. The deocder needs a motor and or headlight load hooked up for the programing system to function. It needs the load so that the system knows that decoder got the signal. If not, it won't take.

Also, a loose speaker, no matter what the size and shape will sound terrible. Speakers need at minimum a baffle, preferably an enclosure to work right. Take it from somebody that did competition car stereo for a couple years, take your time and do it right. Just slaping it in there will not be worth the time and effort.

[skipgear]

You have to have the decoder installed to truely hear what it will sound like. Without the motor hooked up, the BEMF can't detect the load and change the sound of the chuff.

I unsolder the factory decoder from the light board and simply reinstall the sound decoder in the same solder points.  You may be able to vent the speaker out the bottom of the tender, below the lightboard. That would save space and use the entire tender as the enclosure. Be warned that the tender frame is metal though, it will take some work to get though it. You should remove the lightboard and the plastic insulator plate under it from the frame before cutting.

[darticus]

Thanks for the help. These old eyes have to study this better and try what you said. I guess I can drill through the base and use a dremmel tool to grind it. You don't think the speaker will fit up top with some holes drilled in the top of the tender? Ron

You have to have the decoder installed to truely hear what it will sound like. Without the motor hooked up, the BEMF can't detect the load and change the sound of the chuff.

I unsolder the factory decoder from the light board and simply reinstall the sound decoder in the same solder points.  You may be able to vent the speaker out the bottom of the tender, below the lightboard. That would save space and use the entire tender as the enclosure. Be warned that the tender frame is metal though, it will take some work to get though it. You should remove the lightboard and the plastic insulator plate under it from the frame before cutting.