Thursday, July 10, 2014

Planes Trains Automobiles and Sound


I have had quite a busy few weeks, not so much in regards to model railways but mainly to do with work. I have just returned home from a work trip to Townsville, however before I went, I finished modifying the C38 and D57 sound projects to include a shift mode function. While different Loksound projects seem to use varying architecture for steam drive sounds they all seem to include an acceleration set of sound files and corresponding transitions. Generally when the locomotive is accelerated up in speed steps, beyond a threshold set in the transitions, the drive sound will move up into these acceleration files. These files are louder and sometimes give a more full sound creating the affect of a hard working engine. Once the actual speed of the locomotive has reached the user speed setting the chuffs quieten down again. This is a good thing, however I have been looking for a method to simulate a hard working engine during constant speed settings. From what I have read, if your layout has grades these can be used to force the drive sound into the acceleration files thus making the loco sound as if its working harder.  I have not tried this personally as my home layout has been built with no gradients. I am not a fan of gradients on model railways but that is just my opinion.

What I needed was a way to use a function to force the drive sounds into the acceleration files or simply just increase the decoder volume with the press of a function button. I posted on the ESU Loksound yahoo group about the possibility of using the sound fade function to increase speaker volume. The Loksound V4 manual implies that this is possible by adjusting CV133 to a value greater than 128. In real life this doesn't work as 128 is the highest possible value able to be inputted, hence why it is called a sound fader! Really!

Another suggestion I received was to use 'Shift Mode' as the trigger to drive the chuff sounds into the acceleration files. I had a few attempts at this with not much luck. I ended up speaking to Mike Walters (DCC Sounds) about what I was trying to do and something must have clicked in my head. I ended up adding the shift transition commands correctly this time over and it all worked.

One other thing I did was to add Switching Mode along with Shift Mode to the same function. This drives the sounds into the acceleration files as well as halving the locomotive speed. It gives the impression of a heavy load being added to the locomotive.

I have now replaced all the acceleration files with louder more full sounds. With the press of F3 the chuffs slip into the acceleration files. Once F3 is de-activated the sound returns to the normal drive sounds. By pressing F4 the chuffs go into the acceleration files and Switching Mode is activated halving the speed. As with F3, once F4 is de-activated the locomotive speeds up and the chuff sounds return to normal drive sounds.

I have added two videos. The first is the C38 class project and the second the D57 class project. Both utilise a Zimo sugar cube in the smoke box.

These projects are almost finished now. The rolling road has made videoing a lot easier. Highly recommended.

On a slightly different note I thought I would share a few pictures of my trip to Townsville. I was able to do some aerial trainspotting on the way home, something that was quite awesome as we cruised at 140 knots down the North Coast Line. I wonder if the drivers were aware of our 500 foot wingovers passing over the top of their trains? I cant remember where the shot of the other Bell 429 and the train below was taken? It was taken somewhere on the way up north, perhaps Gunnedah?

Not a train but this was why we took the trip.

Hope you enjoy,