Installing an Embedded Power Supply from B5 Amps

[darthoverdrive]

I put this together last year but never posted it, not sure why, but here is is.

Over the past months I’ve purchased a couple of Soloists. The main drawback with them or any headphone amp is powering them. Either you use a shit load of AA batteries or if you’re lucky to own one, a Rockadapter. Fortunately I have an old wall wart adapter that came with a Nobel’s Rockman knockoff. It provides the +6V and -6V that the Rockman requires. It’s a little noisy but then so is my playing.

A few years ago I installed one of the Embedded Power Supplies that Dwight at B5 Amps sells into a Bass Rockman I was refurbishing. The EPS is a small power supply that is installed inside the battery compartment and is powered by an AC adapter. No more batteries or Rock adapters! It only made sense then to install them in my newly acquired Soloists.

I thought there might be some owners who have the same problem, a headphone amp but no good way to power it. I put together an overview to show how easy it is to build and install the EPS. If you’re not up to the challenge then contact Dwight about doing the work for you.

I took a few photos during the build and install process. I wasn’t in any rush but it probably took about an hour from start to finish for each unit. The instructions are easy to follow with pictures to guide you through the build and install. There’s less than a dozen components and five wires to solder to the circuit board. First you mount and solder the components to the circuit board, paying attention to component orientation for diodes and caps. Solder the five power wires and you’re done. After the board is assembled a 5/16” hole in the bottom of the case is required to mount the power connector.

Once these are in place I removed the three wires that connect the battery pcb to the main circuit board. Here’s where I broke away from the instructions. Normally the battery pcb remains in the unit with a small hole drilled in it to pass the new power wires through however I decided to leave the battery pcb out in my unit. Mine had a shield on the lower half of the case but not on the top. The metal spring on the battery pcb wasn’t making contact with the shield either so I decided to leave it out. If your unit has a shield on both halves then be sure to leave the pcb in.

Next I soldered the three power wires from the EPS to the main circuit board. Once all the rewiring and soldering is done I put the main circuit boards back into the case and reassembled it. Now it’s time to test it out. Hook up your guitar and amp to the headphone amp, plug in the AC adapter to the power jack and turn on the power switch. Pound out a few chords from ‘Rock and Roll Band’ and Viola, a useable Rockman!

Hope you find this useful. I think it’s a shame to have a headphone amp laying around with no way to power it.

[RockmanCentralBob]

Very cool and nice to have this option!
Thanks for posting!