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

I’m sure that this product would have been perfect but I need to wire it to a single speaker. I returned it and purchase a mono version instead of stereo. I should have done a little more research before buying this item. Hopefully this review with help someone in future for making the same mistake I made. I installed the mono version with great success and it works fantastic.

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.

This is exactly what I needed to interface my BT player into my tractor. Everything is clearly labeled, there is plenty of power, the sound quality is very good, and the bluetooth connectivity is most reliable. All things considered, a very good value.

Have hours of run time one 3 of these from the same seller. And functions great everytime. Easy to set up for making your own bluetooth speakers. I even retro fitted one into a 1967 f100 am radio.

So ready to use. Those old hard cranking floor stand speakers came back to life in my shed.

I planned on putting this in my classic car so was bench testing it with a 12v power supply. It quickly got hot enough to start melting the power wires and was too hot to touch. So glad I bench tested it vs putting right into the car god only knows what could have happened.

It is a great item, would buy again for sure.

This is a cheap way to get a Bluetooth signal from your phone to the speakers in your vehicle. You can do what I did and gut an old AM radio and mount it in the dash or find some hidden spot to mount it. It does exactly what it’s supposed to do but there are no “filters”. Maybe there’s a way to do that but I’m not aware of it. By filters I mean no compression, no consistent volume, no tone controls with the kit. Sound wise, you get what you get. All that said, $13 including local tax is still a great deal if you want a Bluetooth signal feed. I have an update: About 4 weeks into regular use in my car it would drop the connection suddenly and reconnect. Then it stopped connecting at all. I'm not sure why this is happening. I checked the connections on and it looks like will have to pull the radio back out and replace the unit altogether.

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)

Exactly what i was looking for, nice clear sound for my ammo box speaker i wanted to try making. Ordered afew now to try with different speakers and they all work great! Definitely worth the $20

I bought this to install in my 6year old's 24v dune buggy, bar was really not high. This thing actually works really well and doesn't heat up as bad as i thought it would. It's actually a good choice for the price for any diy speaker setup that doesn't need crazy amounts of power.

I got some old bookshelf speakers from the workplace and needed a small amp to go with it. I got this to print my own enclosure and use the speakers as a simple "bluetooth speaker" for the kitchen. Lo and behold, that little amp works like a champ. My speakers are Roemtech 3.4" / 8ohm / 40W. Worked first at first go, just plugged the speakers, used an old 12V/3.5A adapter. Sound wise, it actually sounds really good. Won't beat a dedicated Hi-Fi amp, but that's not what I wanted it for. Very small, once I design and print the enclosure, it will be very discreet. Only negative - may be a deal breaker for some, but not for me: Even when turned off, the Bluetooth component stays "on". Meaning your phone will keep re-connecting to it if you paired it before. Could lead to unfortunate audio piping if you are not careful. You need to manually "forget" the device in order to be able to re-pair easily something else (like earbuds, car speaker, etc.). Annoying, but for the value, I'm all fine with it.

After hooking it up, and getting it working, which was a breeze and sounded great! One I tested it though, big flaw! The on/off switch does not turn off the bluetooth! If it wasn't for the flawed design that causes this continuous drain the unit is pretty useless for battery powered devices! If you use it on a power pack, no real issue! Just a poor design or production issue (why leave BT on all the time? tracking???. ) You will have to add your own on/off switch to ensure the unit is actually turned off.