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Subwoofer and speakers - general



Unless mentioned otherwise, reference to speakers means the sidelights with speakers (speakerlights). Sub-woofer is the Philips sub-woofer that is supplied with the kit.























When the Audio Out from the PC is connected to speakers, it needs to be amplified. This is normally done:

- via powered speakers that contain an amplifier and are connected to the mains supply

- via a music system when connected to the amplifier

- via a separate amplifier



With the amBX system, the Audio Out (Line Out) from the PC connects to the subwoofer which contains a built-in amplifier. The output is used to drive the subwoofer speaker and the left and right speakers. A cable with a 7-pin mini-din plug connects the subwoofer to the Audio In socket on the wallwasher.


There is no amplifier on the wallwasher. The output to the speakers is taken directly from the wallwasher Audio In socket to the red and white Speaker & Front Light sockets.


The operation of the lights is not affected by the speaker connection as all the light information comes from the PC via the USB connection.  A faulty subwoofer / amplifier should have no effect on the light display. If there is no sound and no light display, suspect a problem (hardware or software) on the PC side, on the wallwasher, or with the wallwasher USB / PSU connections.


Note

The wallwasher needs to be switched on, with a working USB connection, and connected to the subwoofer via the 7-pin mini-din lead for the subwoofer and amplifier to work because the wallwasher sends a 5v supply to operate a mains relay inside the subwoofer to switch the mains supply to the subwoofer PSU on and off. This is the “click” that you hear from the subwoofer when the wallwasher is turned on and off.



7-pin mini-din plug connections

The 7-pin mini-din plug from the subwoofer that goes to the Audio In socket on the wallwasher has seven pins and they are connected as follows (also the the diagram on the Pin-outs page).


Pin 1 - Left speaker negative in from amplifier - to white socket pin 11 on wallwasher

Pin 2 - Left speaker positive in from amplifier - to white socket pin 10 on wallwasher

Pin 3 - Right speaker positive in from amplifier - to red socket pin 10 on wallwasher

Pin 4 - Right speaker negative in from amplifier - to red socket pin 11 on wallwasher

Pin 5 - SBY (0v) to the relay PCB

Pin 6 - +5vDC to the relay PCB

Pin 7 - No Connection




Connecting a sound source to the sidelight speakers

If the subwoofer / amplifier is faulty (or you have no subwoofer but still want to use the speakers on the sidelights if you have them), this can be easily done. However, you will have to have a suitable amplifier (that matches the speakers) between the PC Audio Out and the wallwasher Audio In to amplify the sound from the PC.


The Audio In is a standard 7-pin mini-din plug. It is unlikely you will be able to find one. There are some 7-pin plugs around that are not standard. However, an 8-pin mini-din plug can be used instead and these are easily available. The 8-pin plug does not have the plastic key in the centre. The additional pin on the 8-pin plug is in the centre and when connected to the 7-pin socket, will just go into the key hole.


To make sure that you get the best sound, connect the output from the new amplifier as shown on the connections list above.


You will need to make sure that the phases are correct. If they aren’t, the speakers will work OK, but the sound may be a bit flat.



I’ve gone into details here, but it’s a much simpler job than it sounds. Basically, all you need to do is connect the four output wires from the amplifier to a 7-pin (or 8-pin) plug.


Also see the Audio In pin-out diagram on the Pin-outs page.