Turtlerock Forum

Hi guys-

I recently bought a pair of Filtek/BFE MK5b EQ's from the states. Being from a console, they've got some pigtails on the back, with the power supply just being a 24v, 600mA wall wart.
As it was a 110v supply, I ordered in a power supply rated exactly the same, but accepting 240v. I wired my power supply exactly the same, and fired the unit up. The EQ seems to be working (I can hear the different settings making an effect), but it has a huge rippling hum going through it, and is only passing a tiny amount of signal.

I found a diagram of the pinout here -http://www.prodigy-pro.com/diy/index.php?action=dlattach;topic=25081.0;attach=3143;image
For what it's worth Ausgang- German for exit, Engang, German for entry. In other words, just the in and outs. I've never really looked at pinouts before, so I'm a little unsure if I'm reading it properly.

Everything seems to be wired correctly according to the pinout- except the power supply.

The main rail of the power supply is going to the correct spot for 24v, but the shielding for the power supply is going to the 3rd pin from the bottom on the right, where it is met by a short jumper lead from the ground (bottom right). I assume this is incorrect, but the seller assures me it used to work. Should I move the power supply shield to the 0v position, and remove it's connection to the ground?
Also, I assume the wire shown leaving the ground tab is to ground to the chassis/central ground point. I do intend to rack these eventually, but at the moment they are not racked. Do I need to ground to an external point or have I read this wrong?

Thanks in advance- don't really want to blow it up!

First up, you are using a 24V DC plug pack, yeah? A regulated one would be best but if it is unregulated and the module is in good condition any residual hum should be pretty low.

thus, you want the 0V line of the plug pack wired to the second bottom on right pin with a link to the bottom right pin.

the +V line of the plug pack will go to the bottom left pin.

You should confirm that the image of the connector is showing the same rear view of the connector that you are looking at, not the front view. You can confirm this with a multimeter to measure zero ohms between the chassis and the bottom right pin.

running it off a plug pack you will probably want to link the pin1 or ground side of the audio input and output together and then bring them to the common 0V and chassis ground.

If the module is to be racked, with an internal mains supply there is a prefered way to wire all this that varies slightly from that outlined above, but for now with a plug pack it should work fine.

Thanks Rob, that's great. Luckily the tabs are numbered 1-13 so I can make sure I'm not wiring it upside-down etc.
Followed your advice and all working perfectly! Thanks for your help.

Pretty cool sound cheap EQ's, with quite a lot of control. I am intending to get around to racking them/getting them racked, but I want to put in the hours on them and make sure they do the job first.