Parts Express Executive Portable Speaker Kit Build

I was looking for a portable speaker for using outside and around the house and came across this Parts Express kit. I haven't seen much else about this kit online so thought I'd document my build here and give some impressions.

https://www.parts-express.com/Executive-Portable-Bluetooth-Speaker-Kit-300-7164?quantity=1

I modified my build by substituting in a 5 x 18650 21V battery kit and adding an analog 3.5mm input along with the battery light kit to show me the battery charge level. I had to drill out additional holes in the back for the lights and the 3.55 aux input and then used putty to keep everything airtight.

The instructions call to build the entire box first, but given how tight everything fits, especially with the bigger battery pack, I glued the box together but left the back off initially. Then I built the crossovers and wired everything up before adding the back on last. I don't know how it would be possible to get everything in and wired up with the back on through the passive radiator hole, so I highly recommend doing it this way.

I wasn't sure how many washers to add to the passive radiator as it wasn't included in the instructions. I messaged parts express support and they got back to me saying to use 5 washers for the flattest response. They included the response graph in the gallery linked below: red is for 5 washers, 4 for yellow, 3 for green, and 2 for blue.

I painted the box with duratex and spray painted both clear plastic panels flat black. I was pretty happy with the way it turned out aesthetically overall.

In terms of sound, for a ~300 portable bluetooth speaker I am very impressed. The bass is pretty flat down to about 40hz and there is meaningful output down to about 30hz. With all the EQ nobs set to the middle, neutrality is pretty good, I don't hear any major spikes or dips when sitting on axis doing frequency sweeps. Output from the 21V battery pack is plenty loud for a moderately sized room, though I haven't had a chance to try it outside yet as we are in the middle of winter. Overall I'm very happy and looking forward to getting some good use out of it this summer. Happy to provide more info for anyone interested or thinking about doing this build.

I can't figure out how to upload images on this site (restricted for newbies?), but the Imgur gallery is linked below

https://imgur.com/a/QhyeD5c

 

Man, this is a large bluetooth speaker! 25L+. If it's going to be used primarily indoors I would add even more washers, tbh. I prefer a slightly sloping response. For outdoors use 5 washers seems nice.

What I do wonder about is why there are two coaxials next to eachother... The other portable speakers also seem to be like this

Looks like a really classy build, though!