Pirate Radio - ways to make it louder?


I recently purchased the pirate radio kit and and another phat beat DAC and the additional speaker.

I build a soundboard which plays mp3s from the sd card assigned to external momentary buttons through it and it works like a charm. I have the phat beat and pi zero stacked with an extra long female header and connected the external buttons with jumper cables to the pins.
The hardware, cabling and a 5000maH battery pack fit perfectly in the loot box.

I’m planning to use this soundbox for a 12 hour moped tour and after the first trials it turns out that the volume is way too low. Alsamixer at 95%, pygame vol at 0.9
I haven’t tested the setup with the second speaker in stereo yet, which will most likely make it a a bit louder, but I fear against a moped engine, it’s still too low.

Are there any suggestions how I could make the setup louder?
I don’t care too much about sound quality, but portability and the ability to power it through a powerbank.

  • Would it be possible to get some 15-20w active speakers and connect the cables to the phat beat directly?
  • Is there anything on the software side to put more gain on the amp/speakers?
  • Would I benefit from bigger speakers with the same pi setup?

I’m looking forward to any suggestions, I don’t have additional hardware lying around to test by trial and error.
I also fear that this is impossible to achieve.
My alternative would be to keep the phat beat and pi zero as control box and hook up some external speakers via 3,5mm (through small usb soundcard) or via bluetooth and add a big powerbank to the setup.

Thanks in advance

The pHat Beat is 3W per channel. two speakers should get you 6W. That’s lots of power (IMHO) for say in a room, not so much in a noisy environment though. I’m not sure where you go for more power though, will have to give that some thought?

For a room the phat beat is quite loud, yes.
I ordered a bluetooth speaker which is hopefully loud enough (2x10w) and will leave the 5w speaker connected to the phat beat as default output, and mapped a script to one of the buttons of the phat beat which initiates bluetooth pairing and changes the audio output to bluez. A

I have to see how stable the connection is and how tough the bluetooth streaming is on the battery life of the pi.

With this setup I dont have to buy more parts for this project, the bluetooth speaker can be used for other stuff (and is waterproof).

Thats how it looks like at the moment, a 5000mah battery is inside the loot box, I probably need a bigger one mounted somewhere else on the moped

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Nice build. I added buttons to my Pirate radio too, mini arcade buttons. Mine is in an old subwoofer box with no way to reach the buttons on the pHat Beat itself.

I saw your posts showing your build and they inspired me.

The momentary buttons I have are not optimal, because after it recognizes a button is held (not pressed) they still send a press event when you release them in 95% of the cases. This currently breaks some parts of the software implementation I made with the phat beats on board buttons (mapping different mp3s to depending if button is pressed or held and also a “control mode” which issues some commands, reboot, disable wifi, etc).

I still would like to replace the buttons, but the ones recommended for arcades are too big for my use case at the moment and I already tried two different kinds of cheap ones.

Cool, nice to know my build inspired somebody. I’ve learned to use quick but firm single taps. Especially when adjusting the volume up down. I haven’t done any button remapping etc, just the stock functions. No need to so far. One mod I would like to do at some point is add a small text display to show the title of current song playing.
Anyway, nicely done, enjoy your mobile boom box. =)