Official Review: Spencer (Hardware)

By Prans Dunn, May 9, 2021 (updated May 4, 2021) 11 8

Circuitmess is back with some new DIY projects to get you soldering and tinkering while learning about electronics. This time, we’ll take a look at Spencer, a charismatic DIY voice assistant.
Prans Dunn


CircuitMess has released some great educational and fun DIY products in the last couple of years. Starting with the DIY console MAKERbuino and following up with the DIY Ringo phone, both of which were crowdfunded, the Croatia-based company went back to crowdfunding last year for its new project, the STEM Box. Rather than release products individually and raising funds for each, CircuitMess opted for a subscription model where STEM Box backers get a new DIY project every 3 months ranging from a smartwatch to a voice assistant. Caution should always be advised for crowdfunded projects but CircuitMess has so far delivered on its kits every time.

In this review, we’ll take a look at one such kit from the STEM Box, Spencer, which packs the following specs:

  • Front display circuit board with 144 individually controllable white LEDs
  • 5-watt speaker
  • Main circuit board:
    • ESP32 dual-core processor with built-in WiFi chipset
    • TFA9882 DAC (digital to analog converter) with built-in amplifier
    • Micro USB port 
    • 16MB flash memory chip 
    • Microphone

There are some similarities between Spencer and the Google AIY Voice kit which itself can be compared to a DIY Google Home. But while the Google AIY Voice kit lets you assemble the hardware and tinker with the software, CircuitMess’ Spencer puts you in charge a step before.

Indeed, just like with the startup’s previous projects, you’ll have to get soldering with this DIY voice assistant. With Spencer, this involves the main circuit board and front display circuit board. It might seem daunting at first, especially if you’ve never tried soldering before. But you just need to take the jump and try it by following the tips that CircuitMess provides in its kit-building guide

If anything goes wrong, the CircuitMess team has excellent after-sales service as I attested myself during my build of the MAKERbuino when they fixed the improperly soldered joints and shipped back the unit. And if you did solder before, putting Spencer together will be fairly easy. After having myself soldered the MAKERbuino and the Ringo previously, I found Spencer to be the easiest to build. Within 1.5 hours, I was done with the soldering section and I didn’t even solder anything for over a year!


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I also found CircuitMess’ guides to be more fleshed out and walk you through every step. In so doing, the guide also chimes in regarding what you’re soldering and its importance to the device. So, the recommended age group of 11+ will surely be able to follow through the process while learning more about the world of electronics. But having the supervision of an adult is very much recommended, especially when handling the soldering iron. 

Once the soldering part is done (and checking that the joints were well soldered together), the rest is fairly easy. You’ll just have to piece together the acrylic casing, that Big Red button and Spencer’s arms and legs. I’d like to suggest not to tighten the screws too much as this can crack the casing, like I did with the lower front one.


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And just like with CircuitMess previous products, completing the hardware assembly is only the beginning. You’ll have to first plug in Spencer to your PC to connect the assistant to Wi-Fi and from there, you can start using it by powering it through a separate power source. By hitting the big red button on Spencer’s head, you can ask quite a lot of questions ranging from the time to whether Spencer is Skynet and the assistant will reply in a rather charismatic way.

Spencer indeed feels and sounds different than other assistants you might be used to like Siri, Alexa or Google Assistant. It has an original personality of its own going for it as it leans more on the funny than on the formal side, can “show emotions” on its display circuit board and even has its own (static) arms and legs!

The commands do not end there as you can further code commands for Spencer through CircuitMess’ Scratch-like programming tool, CircuitBlocks. The startup has some programming guides for Spencer where you can get it to display some custom animations, say specific things when the button is pressed and have it repeat after you. You can further tinker with the codes to give the assistant a more personal touch.

However, as you can see from the official video above, there is a noticeable delay in Spencer recognizing your voice input and fetching an appropriate response to output. It’s definitely not as snappy as Siri or Alexa but it tries to make up for the delay with some loading animations while it’s generating a response.

I also found Spencer to be rather large with a dimension of around 11.9 x 8.2 x 8 cm, especially considering the large volume of empty space on the inside. The main circuit board is comparatively small (around 7.2 x 5.8 cm) and the device could have been built around that size by making the display board smaller; and I would personally prefer it to adopt such a more compact form factor.


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Moreover, the number of guides is rather limited at this time as the kit is just shipping. And while CircuitMess says that it has more Spencer coding guides in the pipeline, what you can do with Spencer, through the guides available, is ultimately restricted. The device’s potential is set to grow with community creations, as is common with CircuitMess’ bubbling community, but those creations have yet to be seen.

And for the $90 that Spencer is currently going for (down from $120), you might as well consider the Google AIY Voice kit which comes at $60, including the RaspberryPi Zero board. The AIY kit has been around for longer and hence has more community creations and can also perform more commands than Spencer like reading the news or playing radio channels. And since it’s using a RaspberryPi board, you can even use it as an emergency computer or use it as a retro console emulator.

Nevertheless, Spencer is not meant to replace your home voice assistant nor compete with tech giants’ versions. It is meant to be an educational tool to help users get into the world of electronics and programming in a fun and hands-on way. The Spencer kit achieves that as it is definitely fun to build but its functions remain limited at this early stage. 


Purchase link and discount code

CircutiMess was kind enough to provide a special 20% discount for GBAtemp readers, should you want to purchase a Spencer kit of your own.

Discount code: GBATEMP20

Official store link

What We Liked . . . Fun DIY project Educational tool Handy guides What We Didn't Like . . . Noticeable delay in getting responses Limited apps/commands Could have been made more compact
out of 10
Building Spencer delivers the fun and educational DIY experience that CircuitMess is known for but as a voice assistant, its potentials are currently limited.
Scott_pilgrim, Weyu, KiiWii and 5 others like this.


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