Well, it happened again – the Velodyne SPL-10RGB subwoofer I’m using for my computer audio system bit the dust. A little checking around I determined it was not going to be easy or cheap to replace it with something comparable. Thus, I decided to do another conversion.
This one was a little more of challenge to “passivize” than the little Energy sub was.
Removing the back panel revealed that the banana plug connections were underneath a “second story” circuit board, as shown by the yellow arrow in the picture below, which was held in place by a number of nuts and threaded studs, shown by the orange arrow.
Removing the upper board showed that these banana plugs were soldered directly to the circuit board, unlike the Energy which had wiring from the plugs to the circuit board that was easy to splice into. You can see the banana plugs’ four solder points in the picture below, indicated by the yellow arrows. The two inner ones are the negative terminals, the outer two the positive terminals.
I soldered the wires from the driver directly to those points on the board. I also used a razor-blade box cutter knife to cut through the circuit board traces, thus fully isolating the banana plug terminals from any other circuitry, as seen by the orange arrows.
Lastly, I snagged a little RAMSA WP-9055 amplifier off eBay to power the sub for a measly $100 shipped. So, that was the entire expense of the conversion – way less than the $3-500 it would have cost for something of comparable (small) size and quality, even going with something used.
The RAMSA only puts out maybe 100 watts @ 4-ohms, far less than the 1000 or so watts the Velodyne amp generated. However, I only use my computer system for music and YouTube videos played at moderate volumes, so the RAMSA is more than enough.
So, I’m back in business on the cheap with another “passivized” subwoofer!
Regards,
Wayne A. Pflughaupt