Mackie HR624 Active Speaker – Not switching on

Mackie HR624MK2 active monitor Speaker being repaired

A Mackie HR624 active speaker needed to be repaired as it wouldn’t switch on, which apparently is a common fault.

Mackie HR624MK2 active monitor Speaker

This was a straightforward repair as the fault and repair is well documented and consists of replacing a capacitor, which fixed it.

The Mackie is an interesting and well built speaker that has a 6.7″ low frequency driver along with a 6″ x 9″ passive woofer inside the cabinet that you don’t normally see.

The photo below shows the passive along with the amplifier and power supply board mounted behind the back panel.

Mackie HR624MK2 active monitor Speaker being repaired

Passive speakers don’t have any magnets or voice coils. They basically flap about in the breeze created by the main active woofer thus reinforcing its output.

It looks like it had three TDA something or another amplifier ICs. Their number was covered by a heatsink clip I didn’t want to remove so I’m making an assumption they were all the same.

As the spec was 40w for the tweeter and 100w for the mid / woofer I’m assuming two of them were connected in a bridge arrangement to get the higher power as not many amplifier chips produce 100w.

Please note, I don’t repair Bluetooth speakers or soundbars.