Hello from England, looking for some info on SL3's

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Oh, Martin Logan changed the design so that gravity could no longer damage the wire connection? Strange, because on the Prodigy the panels could still slide down. The brackets ML sent me do work now though.
Yeah, my SL3's (regular plastic connector blocks) has the sliding panels... I don't think they changed that. I was considering doing some router work on the trim pieces & reversing the key-hole brackets, but never got round to it. The little brackets from ML work
These are the notes I received from Martin Logan back in 2018. I'm beginning to doubt myself, however; because the panels covering the woofer are indeed touching the floor (these SL3's are repanelled surround speakers on small spikes for my home cinema).


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So I have tested the HV output using my new Fluke 80K-40 probe (1000:1) into my Fluke DVM.

First I set the meter the AC and used the Probe to measure the line input voltage (240V / 50Hz for me). The meter display 0.244V so a good 244V which is fairly typical.

I then moved the meter to DC Volts and probed the multiplier output, at the connector block BB1

The meter displayed around 0.35V (350V) then as I left the probe tip connected it dropped to 0.15V (150V) At this stage the panel was connected.

Given the loading at the tip of the probe is around 1000Mohm (or 1uA/1kV) I would have expected it to be more stable.

I was expecting more like 3kV I will have to make further investigations. Such as measuring the other speaker which works.

Not withstanding a panel issue this does seem to imply issues with the HV board.


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