MOO-SIC TO MY EARS!

George Dent prefers a quieter life, so he added a simple volume control – and an on/off switch – to a Noch sound module.

I’m lucky enough to live next to a working dairy farm, so I’m used to the sound of mooing at all hours (and the lovely smell!), so Noch’s Cow Pasture sound module immediately appealed. Indeed, it would suit my bucolic ‘Lisburn Lane’ layout, which has a small farm as the main scenic feature. The set contains a small herd of Holstein cows, along with the sound circuit and speaker. While the mooing is pretty convincing, it’s also incessant, rather like the sound of my real-life neighbours when they’re queuing up outside the milking shed on a summer evening. Cows will only be mooing to such an extent for short periods, yet Noch’s sounds are on a constant loop. Therefore, fitting an on/off

toggle switch is recommended and this is simply a matter of breaking the positive (red) power input wire and inserting a single pole single throw (SPST) switch into the circuit. When flipped, the switch either interrupts the power input (switching the sounds off) or allows the ‘juice’ to flow, thus turning the effect on. As for the volume, which I found excessive, connecting a potentiometer between the sound module output and the speaker creates an adjustable volume control. A potentiometer is a manually-operated variable resistor and is often employed in audio volume controls. There are countless types and values to choose from, but I employed a basic 250K logarithmic taper potentiometer (known as a ‘log pot’). These are commonly employed in

electric guitar volume controls and are available cheaply and readily from music stores or online, from the likes of Amazon. As Peter mentions, the power input cables are very short so, unless they’re being mounted on a PCB that’s immediately next to a power source, they need extending. I replaced them altogether, as they were poorly soldered to the circuit board on this particular sample, with standard layout wire employed. Much depends on your layout’s control setup, but extending the speaker output wires, as well as the power input cables, allows the switches and volume control to be housed on the layout’s main control panel, while the sound module and speaker are mounted to

a specific point on the layout, such as under a building (as Peter suggests) or attached to the baseboard or fascia. Now that I’m able to switch the sound effect on and off at will, while adjusting the volume to suit my own tastes, the Noch unit has become much more fun. The default loudness is fine for an exhibition setting, but for a home-based layout, a lower decibel level is appreciated! Moreover, I can now see the attraction of having a number of controllable sound modules to add some variety to the miniature sonic landscape.

Noch’s Cow Pasture set suggests the continuous mooing of a herd on their way to milking or waiting to be let into fresh pasture. The supplied figures ought to be arranged accordingly, as if they’re waiting impatiently for the farmer to open the gate!