Sunday, June 1, 2014

The Big and the Small

Its raining here today and a good opportunity to update the blog. I know I have been flogging the 57 class stuff to death lately, but I thought I would share some installation pictures, a tweaked sound file and the latest sound file installed in my Trax 13 class.

This particular 57 class model, as you all probably know by now is my Uncles. For this install, one of the requirements I set for myself was to make it easy for him to connect the wiring between locomotive and tender. I like to keep brass locomotives in their original boxes, so being able to separate the locomotive and tender is important. Other requirements included having the speaker in the smoke box (where the sound is suppose to come from) and the fitment of an ESU power pack.

The first version of the install included a Loksound V4 decoder, adaptor board and Power pack in the tender. A six wire loom transferred sound output to the Zimo sugar cube, power to the motor and track power to the decoder. This meant the need for a six pin connector between loco and tender. Not the best way to keep the loco tender connection easy to handle.

Heading back to the drawing board, I happened to remember a comment made by Colin Hussey in regards to placing the decoder in the boiler. After once again pulling the loco down, I discovered that there is a fair amount of usable room in the boiler/smoke box area. I pulled the lead weight out of the boiler and weighed it. After weighing up my options (yes I know), I decided to make a brass weight which would house all the components for the install. This meant that there would be no wiring between loco and tender. Measurements were taken and my trusty lathe was put into action. What resulted was a cylindrical brass block, exciting stuff!

Slot for ESU Power Pack

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From the picture you may be able to see the milled recess where the ESU Power Pack will reside. The capacitor was removed from the Power Pack and then remote mounted in front of the speaker. On top of the Power Pack is where the Loksound V4 sits. With the speaker mounted the whole assembly fits nicely into the boiler and is held in place with two tapped 10Ba screws, utilising the original lead weight mounting points. Once assembled it weighs four grams more than the original lead weight.

I was not completely happy with the sound file shown in my last blog post. I have been slowly trying to develop a more full chuff sound throughout versions, however the last attempt lacked some of the rhythm that the prototype portrays. As the decoder sound files are directly taken from a 57 class recording, I was unsure as to why the rhythm was not quite right. When the 57 class prototype sound file is imported into the audio editing software, you can graphically see all six chuff sounds. This makes it easier to work out the timing and amplitude levels of the individual chuff beats. When splitting each chuff sound up, I happened to shorten the distance between the sixth and first beat. It is sometimes hard to pick the point exactly. I went back into the first chuff sound file and adjusted the beginning by 0.1 seconds decreasing the time to 0.07 for the high speed chuff files. I feel that it has regained the correct rhythm, but that's just how I hear it. This sound stuff is very subjective. The rhythm varies subtly due to speed and sometimes acceleration changes. It can be a hard to pick the first beat sometimes which then throws you off the rhythm also.

I have also included another video of my Trax 13 class. Since its first appearance on this blog it has received a new motor and has had progressive sound file updates. It is a beaut little loco and runs around the club layout very nicely. For this video I placed a plastic glove across the track to demonstrate the ability of the installed TCS Keep Alive. Sorry about all the bird and rain noise! I don't even remember hearing the bird, I think its an owl?

That's it for now. I am heading to the Epping exhibition on Saturday. Its going to be an expensive weekend. New RTR stuff released includes SDS NPRX/Y/F cement wagons, OTM TRCs and the Austrains ultimate S truck. I might have to slowly withdraw money out throughout the week so the missus doesn't notice the huge spending spree on Saturday ha ha.

Hope to catch up with all those going,



  1. Linton you have certainly come up with some innovative ways of installing decoders etc, well done. Regards Peter

    1. Hi Peter,

      I hope your doing better now.

      Thanks mate, I guess if we want this DCC stuff we have to think of everything so as to fit it all into limited spaces.

      It doesn't always work out as planned ha ha.

      Are you planning on heading to Sydney for the exhibition this weekend?


  2. Nice 57 sound file Linton are you going to sell the file ? I would be interested and what V4 is it Normal or select
    cheers Peter