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NGG16 Extra: Adding sound


July 2010

I got a question via e-mail concerning adding sound to the NGG16. As the answer might be of interest to more modelers I decided to add a page to my site to offer some options.

"Do you think there is space for a sound decoder somewhere in this model N-scale decoders are quite small. Loksound micro decoders are 28mm x 10mm x 5mm and the speaker is 25mm x 16mm. Would the decoder fit into the boiler? Ideally if the speaker would fit into the drive units, then I would two, one in each end."

Although I do not intend to add sound, I was intrigued by the question and took these specs as a starting point

I made a mockup of the decoder with the dimensions mentioned
I turned my attention to the front tank, but as you can see, the interior is used for a part by insets and strengtheners. I considered it unwise to remove the strengtheners as they support the 0.3 mm thin riveted skin

The front tank isn't long enough. And then there is a vertical motor to be in it when fitted to the truck. No options here. For those still considering, the inside sizes are:
long: 23.7 mm
wide: 25.2 mm, between the strengtheners: 17.4 mm
high: 19.5 mm


The rear bunker gives more hope, sufficient length
No strengtheners either
and a decoder of the afore mentioned dimensions will fit beside the motor with 1 mm clearance
Another view
A speaker will fit but this speaker is a little smaller than specified, it comes from a Bachmann Shay and sizes 23 mm.
It is possible to fit the speaker face down in the aft of the rear bunker. Doing this however eliminates the room needed for the decoder. It is possible to place the decoder in the boiler though, but that would necessitate extensive wiring between boiler and rear bunker.

The red line indicates the raised floor of the bunker in the aft section, the yellow block shows the approximate position of the speaker.

One option to get both decoder and speaker in the rear bunker would be to sacrifice the motor. The loco can run on one, but will lose half its pulling power. Life is all about priorities!!

As you can see the decoder fits easily in the boiler. Parts of the lead inserted could be cut away to make room. But then again, if you place the speaker in the rear bunker you'll need extensive wiring

An option to consider would be to place the speaker under the boiler between the frame plates.
Available width 23.7 mm.
Available height between lowest point of the boiler and the lower edge of the frame plate: 6.2 mm.
You would have to sacrifice some of the detailing like brake cylinder and some levers. You would also have to make an alternative for the strengthener bracket supplied with the kit. Two simple square brass rods could do the job which then can also serve as a base for the speaker casing. Encasing is necessary. If the speaker is mounted without, it will certainly unvoluntarily pick up every single scrap of iron on your track