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Silicon · 8th Oct 2018, 11:07 pm

The manual states that 2.5W at 600 ohms should available at pins 'B' and 'E' of the 6 pin output socket.

To get the impedance matched correctly to a 8 Ohm loudspeaker you would need a step down transformer with a ratio of 8:1. A 240V to 30V mains transformer would be suitable for testing.

If a 4 Ohm speaker is used the ratio needs to be 12:1. A 240V to 20V mains transformer would do.

8th Oct 2018, 11:07 pm	#6
Silicon Nonode Join Date: Jun 2007 Location: Coulsdon, London, UK. Posts: 2,171	Re: Murphy B40D Audio Output The manual states that 2.5W at 600 ohms should available at pins 'B' and 'E' of the 6 pin output socket. To get the impedance matched correctly to a 8 Ohm loudspeaker you would need a step down transformer with a ratio of 8:1. A 240V to 30V mains transformer would be suitable for testing. If a 4 Ohm speaker is used the ratio needs to be 12:1. A 240V to 20V mains transformer would do.