The Sonos ZonePlayer S5 is a multi-speaker wired/wireless device for streaming audio from a variety of devices and services. We happened to have one on hand from a previous project and decided to tear it down and share our thoughts on this product from a mechanical design point of view.
Let’s get right into it; the design is very simple from the outside without any obviously visible fasteners, as usual the first place to look is under any stickers or rubber feet. As expected the S5 has a large silicone rubber pad on the bottom which hides 8 recessed fasteners.
Removing these allows the bottom “foot” to be removed revealing 3 antenna (more on this later). It’s interesting to note the slightly different color seen on the main body underneath this foot, this tells us that the product is likely painted, so getting a perfect color match in the raw plastic isn’t necessary (but getting as close as possible means scratches will be less visible). This was likely done either because the desired texture wasn’t feasible within the draft constraints of this product, or more likely, to match the other materials used throughout the product (the main body is ABS while the base and top are PS).
Even with the screws below the foot removed there was still no obvious path forward, so we turned our attention to the grill, it’s simply a snap fit to the front of the product with the notable addition of hook & loop adhesive to make sure the grill stays firmly in place across its large span. This is important on an audio device as any rattling between parts would be detrimental to the sound quality.
Removing the grill reveals 8 more fasteners which allow removal of the front panel and speakers. It’s impressive to see the efforts to ensure good acoustic sealing, the front panel is sealed with a foam gasket all the way around its perimeter, likely both to prevent rattling and provide a sealed chamber for improved base response. Also improving that response is the porting seen behind the subwoofer, the convoluted path allows the correct acoustic length/volume without making the product larger like a typical subwoofer. This is made of 6 parts all glued/welded together, the high part and assembly cost reflects how important this feature is.
Removing a single multi-pin connector frees the speaker sub-assembly from the main unit. At this point to remove the board we turn to the back and remove the sticker revealing more fasteners securing the I/O components to rear of the main housing.
While this did allow the board to be freely moved within the housing it was still trapped by the 3 antenna wires that support the use of “SonosNet” (which allows you to networks up to 32 devices throughout your house!). These were likely assembled to the main board using standard connectors, and then covered in adhesive to make sure they don’t rattle free. This meant it was easier to de-solder the connections at the daughter board rather than try to remove the connectors.
With the antenna removed we’re able to remove the PCB stack, the use of stand-offs and board to board connectors means the entire PCB sub-assembly can be assembled and tested independent of the whole unit, which is good as you don’t lose the time investment of a full assembly only to find out a PCBA is defective.
With the PCB out of the way it’s now possible to remove the 8 short screws holding the top on the main body. While the vertical height was a little tight there is plenty of room for a driver here, though we’re a little surprised to see Philips rather than Torx drive fasteners. The top piece needs to be separate as the draft required for core side of the main body would have made the wall section too thick when combined with the slight upward bend on the perimeter of the top. While this complicates assembly (8 screws and two pieces of foam to stop rattling) it’s the only way to achieve the desired look.
With the top removed we see a neat little UI board housing the devices 3 buttons, it connects to the main PCB stack via a single ribbon cable. Removing it from the top shows a silicon web with conductive pills over molded onto the 3 buttons. The selective use of clear silicon allows it to function as a rudimentary light pipe for LED indicators to shine through on both the Mute Button and status light.
Overall we count:
- 78x fasteners (7 unique)
- 20x custom die-cut foam pieces
- 12x custom injection molded pieces
- 3x custom metal pieces
- 6x PCBs
We’re impressed with the value seen in the low number of custom plastic part (only 4 for the main housing components) most which are straight pull (meaning a simple and relatively affordable mold). The number and variety of fasteners does drive up assembly cost, but given the high-end nature of this product it makes some sense to use screws rather than plastic features such as snaps as they are more robust and serviceable. Same goes for the foam, there are a large number of custom cut parts, but since sound quality is a major selling point the tooling investment makes sense.
Overall it seems like a product that is designed well for its intended market (mid-high end home audio) but seems to be too assembly intensive to scale to very high volumes.
See the video below for our complete tear down and stay tuned for a deeper dive into specific aspects of this product such as design for assembly, and mold-ability.