One of the first orders of business when getting the ‘Vette rehabilitated from it’s years of neglect was to secure some tuneage. While the factory Delco-Bose Gold sound system may be a little tired, all things considered it’s still a decent sounding piece if you can get past the 20 year old technology (think: cassette deck). Though some would find this car too new to be considered a “classic”, every time I look down at the metal bias button labeled CrO2 it takes me back to the days when mullets and mix tapes were required “accessories” for cruising town. Unfortunately after popping in my pristine cd of Phil Collins Face Value I was disgusted when the head unit spit it back out like a piece of rotten meat. Fortunately a quick cleaning of the laser pickup solved that, and finally In the Air Tonight was playing in all it’s 1981 glory. Now it’s time to bring this factory radio into the 21st century.
After much research followed by some trial and error I was able to pinpoint the analog audio inputs that feed the system’s CDM unit that lives under the storage compartment in the rear hatch area. Click on the picture to see in full resolution – pins 9, 10 and 11 appear to be the ones I’m interested in.
If adding a 1/8″ stereo input cable to the CDM is your thing this is all you need. But I’ve got enough cables in my life, and wanted to go a step further by adding a stereo bluetooth audio receiver. This will require a slightly esoteric power solution so as to eliminate the possibility of a ground loop. The piece I settled on was the av10-24s08 dc-dc isolated power supply. I was able to procure one on eBay for 11.99 from mainland China. I’ve found linking to active auctions problematic, but the product title was “DC-DC 10-24V to 5V 1.5A Car isolated power supply usb charging module Converter”.
This piece – seen here wrapped in electrical tape to prevent it from shorting against the case, provides a regulated 5 volt output via a USB host connector to provide power for the Rocketfish bluetooth receiver ($40 at Best Buy). Note that the orange power wire is routed under the board, but I later found that using pin 4 of the 7 pin portion of the connector also works fine. This pin provides power to the dc-dc converter and subsequently the bluetooth receiver whenever the radio is turned on.
So there you have it – about $55 and a little soldering brings this aging audio system into the present. The receiver stashes nicely in the jack storage bin next to the CDM box, and no-one will be any wiser. Pop in a cd with an 80 minute track of silence, and now my phone provides hours upon hours of classic rock from the 80s and 90s for the rare times when I tire of the soundtrack the smallblock LT-1 belts out through 2-1/2″ pipes and de-baffled flowmaster series 40s. 🙂