Cambridge SoundWorks 2.1 Help

[_Luke_]

Greetings from Nebraska,

I recently picked up this set of speakers from a Goodwill for $10. I didn't know anything about them, but the included carrying case with cables caught my eye. The label on the subwoofer unit reads - "SoundWorks by Henry Kloss, copyright 1996 Cambridge SoundWorks, 1-800-FOR-HIFI, serial number 54637".

After connecting the speakers and powering up the system, I was pleasantly surprised by their clarity and performance. I didn't know what to expect, but they sound great for their size. Upon further inspection, I was a little confused about their power supply setup. They came with a wall wart style power supply rated for 12v output at 1250ma, brand is "yHi power adapter". There is another separate power cable with Edison plug running directly into the back of the subwoofer unit. I assumed at first that both plugs were required to run the system, but unplugging the additional cable has no observable effect while listening to music. The system continues operating with the same output level, no crackle, no pop, zip.

I wanted to investigate further, so ignoring the large shock hazard stickers on the bottom of the unit, I removed the 4 screws and separated the back plate from the MDF enclosure. Below are my findings:
1) A few pieces of loose hot melt glue.
2) The cardboard port tube detached from the back plate, sitting loose in the bottom chamber of the enclosure. I suspect this was old damage from a previous disassembly.
3) The seemingly unnecessary power cord leading to a small circuit board, completely disconnected from the main amp unit and just sitting loose inside the enclosure.

This small circuit board has electrical tape wrapped around it and seems to serve no purpose. Any components on the board have been desoldered and removed, leaving only bare traces. On one end of the board are the power cable ends soldered to AC traces. On the other end sits a small two prong connecter, which corresponds to a cable leading inside the amp module. The space on the board where some component used to live has an "AUTO TEST" stamped on the surface, and the numbers 4144247523.

My plan is to glue the port tube back in place and reassemble the unit. Can anyone tell me what I've got here? I can't find any documentation to explain the purpose of that small circuit board and additional power cable. Is it possible this is a manufacturer test unit, or modification from the previous owner? Should I attempt to find the missing component and reconnect this to the amp module?

Any insight would be appreciated.

Thank you!!

 

[swechsler]

I believe this was designed as a PC speaker system. Don't know much about it, but it was apparently also made without the AC power cord (note the indentation where the cord would have been), possibly for non-American markets. I'd also guess that that's not the original power supply, since the power rating says 30W, which would require 2.5A at 12V. My assumption is that the internal power supply failed, a previous owner removed it and decided to go with an external supply instead. Why they removed the components instead of just cutting the cable is anyone's guess.

 

[homebrew]

Had a pair that I used for computer speakers. They were OK if used within their limits.

 

[dcdiaz]

I have that exact kit on my work computer in white/beige. The power supply looks like it has baked the plastic, so is now orange, but it still works and sounds ok as my desktop.

 

[joelll]

The "Soundworks" speaker system was originally designed to be adaptable to two major uses back when they were made: computer speakers ("multimedia"!), and portable CD players (or other line level sources like a cassette or FM walkman).

When used at home with computer speakers, the 120v plug was convenient. When used away from home (which is the reason for the optional carry bag), they could be fed 12v from a car adapter and still work. The carry bag was designed to fit a battery CD player and be able to play and be heard without removing the player and satellite speakers from the bag. The wall-wart 12v power supply is some random aftermarket adapter.

The 1/8" plug wiring was designed to reach from a tower case computer sitting on the floor up to the volume control top of the desk (they included a little velcro to stick it down), and then the second wire back down to the subwoofer under the desk, which had speaker wires supplied long enough to place the satellites on top of the desk.

It looks like your example has had someone mess around inside and remove components from the 120v power supply board, which leaves the 120v cord useless. If it runs fine with the wall-wart adapter, then you should run it that way, and can even cut out and remove the 120v cord and the unused circuit board.

The Soundworks sub/sat wasn't terribly expensive back then, but it wasn't super-cheap. I used one for my desktop sound right up until 2018 or so. Be careful with the plastic spring clips for the speaker wire, they get brittle after so many years.

CSW's better travel speaker system was the nifty Model Twelve, which featured a small hard-case subwoofer suitcase, with a small integrated amplifier with line-level inputs and slightly larger satellite speakers and wire stored inside, very well suited for travelling.