This round speaker fits many of the Atlas locos that were designed for sound – they usually use a pair!
Handles more power!
Doesn’t need a dropping resistor!
The SP-30R-08a specifications are:
30 mm in diameter x 4 mm deep
1.2 inches in diameter x 0.16 inches deep
Impedance is 8 ohms
Power rating is 0.2 watts – no need for a resistor with 1 watt decoders
Sound Pressure Level is 89 dB
Frequency response is up to 20KHz
If you are using two of these speakers together, they need to be in series and in phase. What means is that the red wire on one speaker connects to the black wire on the other speaker – yes you can shorten them. Make sure this connection is insulated, we recommend 1/16 inch shrink tubing for the task. Then you connect the remaining red and black wires to the decoder.