Two speakers 13 mm, 8 ohms, round, 1-2W with sound chamber speaker for LokSound V4. 0 LokSound micro V4. 0Beim Choosing the speaker of the type of decoder used is crucial. Depending on the decoder, different speakers are suitable: LokSound V4. 0 and LokSound micro V4. 0 decoders require the new speakers with 4 ohms impedance. With the previous 100 Ohm speakers you will hear hardly anything. Conversely, you may for the previous LokSound V3. Never use 5 4 Ohm speakers. This could destroy the decoder! In a decoder swap so the sound-speaker may have to be mitgetauscht.