Walfront ZK‑502L Bluetooth Power Amplifier Board 5.0 Stereo Audio Receiver Dual Channels Digital Audio Amplifier Module for DIY Speakers 5-24V

Very impressed by this little item. I used it to replace an antiquated CD system in a infrared sauna. Connected it to an unused 12 volt DC lights circuit on the sauna control board. Audio quality seems great. I hear no distortion or feedback. I only have it at half volume using the volume knob on the unit itself then controlling volume with my phone beyond that point. I think it could exceed the ability of the speakers that are currently installed. With the current setup it can go louder than I would ever play it ( two 5" speakers directly to this unit relying entirely on the amplification of this device to drive the speakers) I was able to connect via Bluetooth with my phone with very little effort. Shows up as WZ-BT5.0 I'm able to keep my phone 20 ft away with no disruption in connection.( haven't tested further than that it could potentially work from further away but I haven't tested since it wasn't required)

This small bluetooth amp is amazing. I had a Bose Wave Radio/CD player, which is well known for its big sound. Unfortunately the capacitors dried out and the Bose Wave Radio stopped working. I completely gutted the electronics inside the radio case, but kept the excellent speakers and baffling system intact. I hot glued the ZK-502 in the case, wired in the speakers, and wired in an Asus laptop power supply I kept when the computer was obsolete. I also wired in an LED light be hind the green screen so I can tell when its on or off. I also purchased an $8 remote control outlet so that I can turn it on and off. The results were fantastic! I the amp powers the speakers beautifully! Which is amazing at the cost of $13. The bluetooth connection is immediate when it is powered on. I either connect to my Mac or Phone. If you want to change from one to the other, you do have to disconnect from the other device because in can only connect to one at a time. I couldn't be more pleased with it. I have given knew life to the Bose Wave Radio, which is not a radio anymore but a bluetooth speaker, with the same great sound. Actually, I like this better because streaming music has largely replaced CDs and with the tune in app I have all the radio stations I need across the world. Right now I give it 5 stars because it works and works well. How durable/reliable it is only time will tell. If it dies within a year, I will update my review.

I was wanting to tinker with something like this to see if it would work to add Bluetooth to my old car. It powered up and has great sound for the size and price. I've only tested it in the house but I'll soon be setting it up in my 53-year-old Buick that only has an AM radio. 3/29/2025 Update: I finally wired it up in my dash with a set of stereo speakers. It works very nicely. I wired it to accessory and ignition so it doesn't run the battery down. I used Velcro to attach it to the radio bezel.

Excellent choice!

Excellent quality. great sound and volume level. easy bluetooth connection. great value.