Stereo
A brief summary of my adventures in custom car stereo construction
Disclaimer: I, the author, make no claims of quality of the work on this website. Any person or persons who choose to consume the content on this site do so at their own descretion.
In 2019, the OEM Pioneer stereo in my ‘97 Miata failed. Immediately I began brainstorming amazing and expensive replacement options before settling on a 2wpc amp and bluetooth module from aliexpress. For what it’s worth, this solution was shockingly adequate, and might not have needed replacement if it wasn’t for the want for more volume when driving with the top down.
The first upgrade, mostly visual, was a Realistic brand Equalized Power Booster. This claims 40wpc and takes speaker level input, but more importantly includes a stereo analog VU meter. Likely due to my inadequate installation, it also unfortunately includes a fixed volume alternator whine that is unbearable unless masked by high volume audio being pumped through the system. Also, it required a bit of trimming of the dashboard. But hey, it looks sick, so who cares?
Next was a 15wpc amp, also from aliexpress (or ebay from China. Regardless, it was pretty cheap). This IMO is about as much power as anyone needs in a car stereo. It also introduces the first real pitfall of my shoddy construction techniques: Hanging the entire amp off the potentiometer might be a fine idea for a desktop solution, but in a car as vibratory as a Miata it was never going to last long. Eventually the pot failed, at which time I replaced it with a new pot, this time connected via 2 inches or so of 24? AWG wire so that I could separately mount the amp on standoffs. An unknown failure eventually pushed me to just replace the pot with a fixed voltage divider and use phone volume.
Around the same time as the 15wpc amp, the cheap bluetooth receiver was replaced by an AptX capable model from TinySine, which included a microphone input and pads to wire up media controls. I would absolutely recommend this to anyone looking to build a similar solution and am including a link to their shop at the end of this post.
The present and future
Well, the bluetooth board is dead and it’s entirely my fault. I broke it on the bench while testing some other changes. I’ve been looking into replacing the entire system with a Dayton Audio board from Parts Express. It seems like it would satisfy all requirements while also including DSP! If the DSP works out that would be fantastic as I pretty firmly believe that all car stereos should include an optional compressor stage. The noise floor while driving is just so darn high, so if you have any concern for your eardrums there is a lot of music with dynamic range that exceeds the available range. This range is even narrower when driving a convertible at speed.
I would also love to eventually have an aluminum panel laser cut with etched labels for all controls. For now though, scrap aluminum and a label maker will do. This should be a nice upgrade visually from the current scrap of ABS with the orphaned mounting holes outnumbering those in use.