Digitrax SDN144A0 Sound Decoder for N Atlas GP38 "& Similar"?

[tehachapifan]

OK, so the question is; what's "similar" to the Atlas GP38? I'm thinking about trying out a sound decoder and was thinking about putting one in my (DCC ready) Atlas GP9. Since I don't own a GP38, I have no way to tell if the stock DC board sizes are the same. Anyone happen to know if they are or know of a better option? I've notices that, in searching around for sound decoders, there seems to be a lot of mystery with what they will fit in and how many lighting functions they have. I want reasonable sound but also the ability for headlights and gyralights.

[Bendtracker1]

http://www.digitrax.com/products/engine-matrix/decoder/

[tehachapifan]

Thanks. For some reason I thought the Decoder Selector only gave you non-sound decoders. I see now that it does sound decoders too and also see that this decoder covers pretty much everything but the GP9.

[mu26aeh]

Here's thread on sound install on GP7, which should have same chassis as your gp9

https://www.therailwire.net/forum/index.php?topic=31186.0

[tehachapifan]

Thanks. Yeah, I saw that before. Seems the learning curve is pretty steep with those decoders (at least for me). Such as, I don't understand how you download sound into a decoder. Does a PC need to be hooked up to the layout or programming track?? It also doesn't appear super easy to purchase those either or tell exactly which decoder would be the best.

[peteski]

...there seems to be a lot of mystery with what they will fit in and how many lighting functions they have. I want reasonable sound but also the ability for headlights and gyralights

Actually according to something I read on Digitrax website, this type of identification is not very difficult.

For example, in SDN144A0, the "S" means "sound decoder" "N" means it is deisgned for N scale (but of course that just means that it is small enough to fit in N scale locos), "1" means it can supply 1 Amp to the motor, the first "4" means it has 4 functions (2 are headlights by default), the second "4" is the generation of the decoder's firmware (4th generation).  I think that from the 2nd generation on, the functions can be assigned lighting effects. Then the "A0" means specific version or shape of the circuit board designed for a specific application".  Majority of Digitrax decoders can be easily identified that way.

I use Digitrax non-sound decoders, but in general I'm not very impressed with their sound decoder's functionality.

[tehachapifan]

Thanks, peteski. Yes, I am (mostly) aware of the Digitrax numbering system.

[reinhardtjh]

I use Digitrax non-sound decoders, but in general I'm not very impressed with their sound decoder's functionality.

In general, the Digitrax SDN144 series (SDN144PS/A0/A1/K0/K1) has a pretty poor rep in the sound community.  Digitrax goofed in the design of the power supply and quite often you will find that the loco will slow down or stop if you should try to have it (1) moving, (2) Making it's normal prime mover sound and (3) blow the horn because the decoder just hits the wall in current capacity.

Searching the webs for information will lead you to many instances of people complaining about this.  Pretty much the only solution is to turn off BEMF (even that doesn't work sometimes) although in the Yahoo group for Digitrax Sound John McMasters just posted a tuning fix that I hadn't seen before.  I don't know if it works as people seem to report many different "fixes" and few have the same results - it seems very specific to the loco/speaker/environment.

The newer SDN136 and SDXN136 decoders have gotten a much better review.  The catch is that Digitrax has not released and "Plug-n-Play" versions yet. Just the PS wired ones.  But the SDN is the 8-bit sound with 3 voice channels and the SDXN is the 16-bit with 4 voice channel version.  John McMasters has been doing wonders with the new versions - figuring out AJ's programming language like no other.

The other catch - for me at least - is that with only 3 functions, there are not enough for alternating flashing ditch lights on modern diesels which requires at a minimum of 4 functions.  However, the ESU Select Micro's are "only" $20 more than the Digitrax SXDN136's ( ~$80 vs ~$60 street price) so the premium isn't killer and the Select Micros are smaller, sound better and have better motor control.

[tehachapifan]

Thanks, John. Regarding the ESU decoders, I think I saw that you need to download the sound files into them. If so, how exactly is this accomplished?

[reinhardtjh]

Russ,

  Most ESU dealers will download a sound file into the decoder for you.  If you have a LHS that does ESU check with them.  Otherwise I know Streamlined Backshop will and they have a very good reputation.  Using them as an example, the ESU LokSound Select Micro decoder is part # 73800. http://store.sbs4dcc.com/ESU73800LokSoundSelectMicroNMRADCCSoundDecoderNEM6528-PinWiredP.aspx

On that page you have a choice of ordering a blank decoder or having them install a free ESU download.  What you do is go to the ESU Select sound page and find the proper file for your application.  The EMD GP9 would be the EMD 567C engine with a roots supercharger.  So you go to the ESU website - http://www.esu.eu/en and choose "Downloads" --> "Sound Files" --> "LokSound Select - Made for USA" --> "Soundfiles for general usage"  or http://www.esu.eu/en/downloads/sounds/loksound-select/loksound-select-usa/

Then you look for the best fit to the locomotive/engine.  In this case I believe it's the "*EMD 567 16cyl. Non Turbo*"  Since you have a Select decoder you want the # that starts with 738xx or 73836.  That's the number you put in the Streamlined Backshop page for the ESU file to download where it says "Soundfile Number".  You will probably want to order one of their "Sugarcube" speakers to go with it if you plan to follow JDColumbo's install.  JD used the Knowles Fox speaker (now unavailable) which was 9mm x 16mm so this one should work as well "Sugar Cube" Speaker 9x16mm 8 ohm .7 watt w/ Sound Chamber although this one ( "Sugar Cube" Speaker 8x12mm 8 ohm .7 watt w/ Sound Chamber is a bit smaller and is like the Star Micronics SCP-08b which also is no longer made.  Withe either you can remove the sound chamber and make a smaller one like JD did in his installs which will better fit into the GP9.

Streamlined Backshop is in Indiana so is fairly central to either coast, but if you want to look for another dealer then ESU has a dealer page and you can look for others.  Litchfield Station also has pretty good reviews and will download sounds.  There may be others if you Google them.  I, personally would go with Streamlined Backshop online.  I also have the option of a local shop (DCCTrain LLC) that I buy decoders from and can do the sound file installs.

I know this looks fairly complicated, but if you poke around a little it all begins to make sense.  The other options is if you happen to have a friend with the LokSound programmer, then they can load any sound you want into the decoder.  You just download the sound file from ESU and install it.

[tehachapifan]

Wow! Thanks, John! That's extremely helpful!