Soundlab A3 high voltage circuit

[Klarskov]

Hello!

The static charging circuit of a friend's Soundlab A3 loudspeaker has (more or less) stopped working (it supplies about 2 kV at most as opposed to a max of around 12kV). Does anybody have a schematic of the "black box" - or does anybody know if a replacement is available?
Any help is greatly appreciated.

Hans J. Mortensen

[bolserst]

Originally Posted by Klarskov

The static charging circuit of a friend's Soundlab A3 loudspeaker has (more or less) stopped working (it supplies about 2 kV at most as opposed to a max of around 12kV). Does anybody have a schematic of the "black box" - or does anybody know if a replacement is available?

Does the high voltage "black box" look anything like the one below for the Soundlab A1?
If so, I believe it is one of the CS2091 series HV modules made by HV Power Solutions Inc.
You could try to contact them, although your best bet for acquiring a replacement is probably to email Soundlab.

Have you tried swapping the interface units between speakers to verify that it is indeed the power supply and not a leaky panel that is pulling down the high voltage module output? Alternatively, you could try disconnecting the diaphragm connection when measuring the voltage to see how much it loads down the supply.

[Klarskov]

Dear bolserst.
Thank you for your reply! The "black box" on my friend's Soundlab does not resemble the one you show - but it may nevertheless be a way of getting the old speaker up and running again, so thank you for the tip.

I measured the HV with the electronics completely disconnected from the electrostatic panels, so I am pretty sure that the HV circuit is at fault.

However, I have communicated with Soundlab, yet so far they have not come up with a solution - but friendly they are!

I plan to hook up an external HV supply to the panels to check if that makes the faulty one play again, but I haven't had time for that yet. I'll keep you posted.

Hjkm.