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Oram BEQ 24 Series Retrofit Power & Ground Distribution
Oram BEQ-24 Series Consoles have a few design flaws that cause noise and crosstalk problems.
The main problem is power and ground distribution. Over time Oram changed their power distribution system to try and solve these problems.
In the first consoles +/-18V and Ground was connected to one of every eight input modules. Later Oram added local power supply filtering and applied up power and ground to one of every four modules. One of the problems with this system is that power was still daisy chaining between modules and that ground was not coming from multiple places.
Power enters the top module but the power buss is across the bottom modules. We have created new local filtering circuit boards that distribute power to every input channel. We have also replaced Oram's copper pipe ground distribution system with a tapped copper bar. This allows us to distribute ground without relying on tenuous copper solder joints as we have found in Oram consoles. Below is a brief instructional to replacing the power and ground distribution.
The Kit includes:
(1) Middle Atlantic BB-40 - Ground bar with mounting blocks and hardware.
(1) Local power supply filter board per eight channels.
(2) Ground wires per channel.
(20) 8-32 Screws and tooth washers per eight channels.
Drill the mounting holes.
Mount the ground bar blocks and ground bar.
Vacuum out the frame to remove metal shards from drilling.
Screw in the ground wires spaced out for the input channels.
A 32 Channel power supply distribution system.
Mount the distribution boards.
Attached distribution board ground wire.
Attached master ground.
Bundle ground and power wiring.
Cable tie the upper input module ground wire with power supply wires.
Cut power traces on the lower module top connector. The easiest way to do this is to use a razor blade making two cuts in the traces and then with a hot soldering iron push the broken piece of trace off the board.
Repopulate the frame connecting ground and power wires to each upper input module and ground to each lower input module.
