Wednesday, December 30, 2015

XPT Sound - Part 2

I hope everyone had a great Christmas. Danielle and myself had a good time however are happy to be back home after a fair amount of travelling.
Before Christmas I embarked on another XPT recording session. Blacktown railway station was a real eye opener. Never before have I seen so many ankle trackers in one place. Glad to be alive still!
I now have better XPT horn recordings. Still, these recordings have been by far the most challenging recordings to edit. For the XPT project, if the applicable function button is held the corresponding horn (there are three horns) will play a full 4 second burst and fall silent. If you only want a short horn burst you simply deselect the function quicker. No function room on this project for three separate long and short horns.
As the XPT project is really my first full blown attempt at a diesel project, I thought I would try and modify how the general diesel sound flow works. While I am sure there are third party sound developers out there that have already paved this path, I personally have not come across anything that suited me.
What didn’t suit me:
Generally when you accelerate an ESU diesel project, the model accelerates at a set momentum rate and the sound flow increases as per set thresholds. These thresholds can comprise of multiple factors. This all works well.
It was decelerating that bugged me a little. When a locomotive comes up to speed and no more power is required, say cresting a hill, accelerating up to track speed, drifting down a hill, the throttle is generally shut off an amount that suits the conditions. This could mean the throttle is simply backed off one or two notches or placed back into one notch (I won’t say placed into idle here as I will have a flurry of people tell me how a diesel locomotive should be driven). What I am trying to say here is that the throttle directly effects the prime mover engine revs. Track speed is a product of environmental and power requirement factors.
When it comes to models fitted with sound, generally the locomotive speed needs to be decreased so the sound flow transitions into lower notches. This in a way creates the sense that the locomotive is being braked by the throttle.
ESU have ways of detaching the engine sound to driving speed in the form of manual notching. This however can be a little cumbersome and I really wanted a method of doing all of this by throttle manipulation rather than function button playing.
Some may not agree with this thinking.
The XPT project:
Here is another badly filmed movie! It's a shame that the function buttons did not show up better in the video. You can just make out the selected function button by the border that appears around the box.

My XPT project now has the ability to let you travel at track speed and ‘coast’ with the engine in any notch, all selected with the throttle.
If accelerated up to speed step (SS) 22 (I always use 28 speed steps), the XPT engine will accelerate up to throttle notch 5 (max throttle setting for an XPT) and track speed will build as per momentum settings. I have used speed step 20 as one of the thresholds for the diesel engine sound being at maximum revs. This was to help simulate a hard working XPT while traveling at two thirds max track speed.
Once the XPT is up to speed (SS 22) and the throttle is decreased down one SS to 21, the XPT engine will progressively come back to notch 1. As the throttle is still selected at SS 21 the models track speed remains relatively constant. The XPT will maintain notch one and track speed 21 for good if no change is made.
Once the engine sound has settled to notch 1, by increasing the throttle one SS, back to 22 the engine sound will progress back up to five notch.
If for instance we are travelling at SS 22 again and we want to decrease the throttle to four notch without effecting track speed, you simply move the throttle to SS21, listen for the decrease in engine sound and then reselect SS22 and the XPT will remain in four notch. If three notch is then required move the throttle to SS21 again, listen for a decrease in engine speed and then reselect SS22 on the throttle. The engine sound will then remain in three notch however track speed is still set at SS22.
Once again if the throttle is increased one SS, to SS23 the engine will once again move to notch five.
Another feature is the incorporation of a function operated brake. When the braking function is used, the XPT will come to a stop faster. Braking times are adjustable by changes in momentum setting. When the brake is applied and released brake pipe sounds are heard. When the loco is stopped with the brake function, braking squeal is played.
For me this has added a little bit of fun to the project and once being operated on a layout, will make it quite a challenge to stop at a platform. Just like the real one.
As in my last blog posting, the project still allows for one XP power car to operate in service mode (engine speed remains in two notch). This is function button selectable and applies to the trailing power car.
I am happy with this project for use in the XPT. I think a diesel freight locomotive, for most prototypical realism would need a similar throttle notching set up for when increasing engine speed also. Perhaps one day.
Decoder Installation:
For the XPT I used two ESU V4 21 pin decoders, two ESU Power Packs and two Zimo LS 10 x15 sugar cube speakers.
The XPT install was one of the most straightforward I have carried out. The strobes, headlight, white marker lights (ditch lights) and red markers are all wired individually. The blue and green wires are both commons for lighting (markers and ditch lights). These commons run through two of the switches under the fuel tanks. The grey wire is connected to the red markers and the yellow wire is connected to both white markers and ditch lights. You may be confused here - I was. Weirdly if the blue wire (+) and the yellow wire are powered the white markers light up. If the green wire (+) and the yellow wire is powered the ditch lights illuminate. I found the lower lighting board impossible to open up for fear of breaking it. This means, to separate the white markers from the ditch lights will require the green common wire to be isolated. This will be possible by using an amplifier circuit switching the positive side, utilising one of the decoder logic only outputs.
The headlights and strobes are connected through a 4 pin connector. The lighting connections are already made to the 21 pin plug. All that is required is to map the functions correctly.
Pin 15 - Aux 1 [1] = Strobe - These have been mapped to flash when the horn is blown. May have to fix up the cabin disco. I didn't notice all the flashing in the window until I watched the video!
Pin 14 - Aux 2 [1] = White Markers – This requires soldering onto plug (yellow wire)
Pin 7 - Rear light output = Head light
Pin 8 - Front light output = Red Markers
I also swapped the motor wires around as I think they were wired backwards. I am using the same address for both loco units and have simply used the ‘reverse direction’ option on the trailing unit. This allows all the direction features to operate properly.

That’s About That:
I am yet to run my XPT set on a layout but so far running on the rollers looks favourable.
I need to thank Dave for being so helpful in allowing me to record the XPT. Much appreciated and a copy of the file is all yours if you want it.
Now to get on and weather the set. This could be interesting!
Thanks for looking. Have a great New Years!


  1. Linton

    Well done! Very intriguing, an eight notch diesel would be interesting, better than the manual notching play the musical instrument idea.

    Ray P

    1. Thanks Ray. I really would like the V4s to offer a better diesel experience.

      As the ground work is done regarding the drive scheme, an 8 notch diesel project is realistically a recorded locomotive away.



  2. G'day Towelly,
    Great video mate, love your hard work you put into perfecting the sound your ears want to hear!! So with that a question?? recently purchased Auscision's knee trembling X class(man its gorgeous)and want to put icing on the cake with DCC sound decoder(available Jan) in your opinion are ESU a good decoder?? Pro's and Con's don't hold back, any help would be great, ESU are fairly new to me..
    Thanks Mate,

    1. Thanks Matt.

      I have not seen the Auscision X yet. I will have to take a look at one now with your positive comments.

      Regarding ESU decoders, realistically if you want the sound file to sound like the prototype, ESU is the only way to go at this point. Zimo decoders are also customisable however in my opinion are not as flexible as the ESU product. Both these methods require somebody to build the customised project.

      Other decoders do offer American type engine sounds which could possibly suit the X class, however the prototypes horns and specific sound characteristics may not be available.

      I will limit the pro's and con's to the V4 sound decoder family. The selects are basically the same however customised sounds can not be created by the user and the sound schedule is not available for editing. ESU seem to use the selects for OEM sound projects. I have a feeling that the SDS 81 class will have a sound project built by ESU specifically for the select type decoder.

      ESU V4 Pro's:

      - Completely customisable - sounds and sound flow schedules,
      - When used with the ESU command stations (ECoS), the railcom feature is very good,
      - Offer ABC constant braking (as do Zimo and Lenz),
      - I think they are brilliant for steam projects,
      - Many prototypical sound features can be replicated,
      - Offer very good motor control,
      - I have not found anything that can not be achieved yet. They are very flexible. Its up to your imagination really.


      - Expensive,
      - Momentum factor does not conform to NMRA standards,
      - If you want to build your own projects there is a little to learn. It will take time,
      - Only four amplified function outputs. The fifth and sixth require amplification to power lights e.t.c. This applies to the micro and standard HO sized V4 decoders.

      The good news regarding the X class is that Mike Walters from DCC Sound (Vic) is releasing/has released an X class sound file for the ESU V4.

      The projects supplied from Mike are always locked, because of all the work that goes into them, so changes to the way in how they drive (sound schedule wise) can not be made.

      At this point, if you want prototypical sound and also want to modify the way in which the locomotive drives, as I did with the XPT, you need to start from scratch.

      If you require prototypical sound and are happy with how most decoders drive then Mike's sounds, loaded on a V4 will fill that gap.

      If you can handle a more generic sound project, then ESU Select decoders along with other decoder manufactures can be looked at.

      I hope this helps. I am very happy with ESU. I use the ESU command station and will be buying their new wireless throttle. The quality is great and the models run beautifully. Building sound projects has become just another aspect of the hobby for me. One that takes up a little too much time ha ha.


    2. I thought I would just add, in case it seems confusing what I am talking about by sounds and sound scheduling.

      Sounds - these are the individual sound files that are loaded to the decoder. These are taken from recordings, edited and placed into appropriate areas of the sound schedule. These are what you hear.

      Sound Schedule - This in a way is a map (flow chart) and determines what sound files are played and when. They are linked by conditions and these set thresholds and boundaries for when sounds progress. This flow chart is completely customisable, it can be built from scratch. This controls when the sounds are played.

      If you are interested, down load the LokProgrammer software from the ESU website (it's free), down load a project from the website also and have a look over the sound area. By opening the individual sound slots you will see a cob web of sound flow chart boxes and conditions.


    3. Linton, Perfect mate exactly what I wanted to read the info you have supplied is invaluable!!! I will skip over to ESU and have a look, yes after proto sound and running capabilities, have also read ESU are a bitch to run with other decoders,I am after a mix of I suppose and really don't favour one or the other, just after a fair dinkum review which you have given, only experience is a Powerline T class space tight for speaker(micro)and TCS wow diesel decoder, TCS sound, brilliant, control brilliant, 30+ horns sound amazing(quill effect for horn knocked me off chair) but no proto for T class, only tested on 5ft run on work bench(all I got atm) positive outcome but this was also an expensive investment bought o/s with really no idea what I was in for, I have also read that once one delves in manual cv tuning on TCS the way it has been set out(cv's)turns into thousands of options endless computing that's enough to send me to the bedroom, draw the blinds and lie down, I do like the K.I.S.S. method, anyway thanks for the great info I will investigate, mate can I? how do I? send you a private message?? Thanks Towelly...

  3. Linton
    I think that set up works well, have to listen/watch the video, but I like the way you have set the ability with the back & forth of the SS's in fact that really is very typical of XPT operations. Certainly if you can achieve that with the 8 notches of a diesel should be a very good project to watch as well.
    You would likely need to seperate the engine revs/power up & down set in each advance of 4 after notch 1 which becomes just power but no revs, prototyp ops, then revs & power ups at each 4th equivelant increase, & drop back by perhaps 1 each steop.

    1. Hey Col,

      Yeah I think having the sound schedule 'playable' with the throttle is a step forward. I have been doing that with my steam projects now for a couple of years so it was nice to sit down and try to improve diesel sound scheduling.

      Still a way to go. The beauty of the ESU V4 is that it can always be updated with new projects and new features.

      Hope your knee is getting better.