Doesn't the STBY light extinguish to indicate switch on???

Hmm... I don't think it did, but I'm not sure anymore. Need to check that if/when I have the energy to rig them up again.

The amps worked fine anyway, I was just wondering if there's any way to see if the "brains" work without speakerlink/powerlink connections. I don't have any suitable cables and wouldn't like to purchase them right now, as the speakers will be staying in storage until I get me a wall 🙂 Thus no idea what length I'd need...

I just checked mine (Powerlink cables though) and the red STBY lights go out when the amps switch on.

I checked the service manual, and the internal "on" signal for the entire amp comes through the CPU, so it must be working or the speakers wouldn't even turn on.

Furthermore, there's only one common control for the backlight and the standby LED, so when one is off, the other is lit and vice versa. So I guess the end result is that when these are connected through the line input, the STBY light stays on and the display backlight stays off...

So, as soon as a voltage is seen on the line input, the amp switches on with backlight but the display is blank 'cos there is no data signal and STBY is off.

Is that correct?

Well, that is basically what I wanted to know! At least this pair of 5000's doesn't seem to do that...

Hmm!!

Just hooked up spare Lab 3000 amplifier with signal jenny input 1 kHz sine wave into Line In socket with jury rigged old BL6000 driver to monitor output.

The red light stays on and back light does not come on. Sound comes from speaker. It would appear that you use the slide switch on side of amp as on/off.

Best I can do for you Mika.

Thanks a lot Graham, seems like it is normal behaviour then.

I actually just brought one of the amp modules home, and I'll try to rig up a Speakerlink connection to a BM5500 with loose single wires if it won't make me rip my hair out. That should tell if the display comes on at all...