Dispelling Some Myths

Listen, I have no doubt that the folks that start some of this have the best of intentions, but it’s gotten old…

I made a video that addresses a couple of things that seem to have become “gospel” on the xLights and FPP forums, with a handful of evangelists insisting that everyone do things the way they recommend because the alternatives are terrible and just don’t work.

While everyone’s situation is different, and they aren’t necessarily giving “bad” advice, doing things the “wrong” way has been working for me for three years now. Other folks feel the same way I do, and are also successful doing things the “wrong” way. If you do post that it works fine for you- you literally get spammed with comments about how you are wrong, and how it doesn’t actually work! (How come our show is running, with people happily watching and listening to it every night then?)

Similar things happen if you dare post that you run a 5v show, instead of 12v, but I digress…

The two things I want to specifically address are:

1 – You can’t have your FM transmitter anywhere near your Raspberry Pi or other audio source. You need at least a few feet with shielded audio cable between the two. (I’ve heard 5-6 feet or more.) Otherwise you will experience random reboots and audio problems.

2 – You absolutely have to use a SoundBlaster USB audio dongle because Raspberry PI audio is “crap”. (There are even graphs to prove it!) How can you subject your show listeners to the foul garbage that the Pi’s audio jack spews forth?!

Edit: Of course I did this without a script… The audio cable is very clearly visible in the first part of the video. For some reason, I didn’t see it plugged into the RPi on my phone’s screen. It’s a nothing-special cable that came with a bluetooth transmitter I was playing with a few years ago. The Pi 4 was new last year, and I previously used a Pi 3B+ in a similar configuration with similar results. More information about our Show Runner (Master) controller can be found here.

The bottom line is neither of the above is true, and many folks run setups similar to ours. Some want to put the transmitter and Show Runner in the same waterproof box (the horror!), and don’t want to buy extra hardware if they don’t have to.

I’ve also seen many posts from folks who have had problems with USB on the Raspberry Pi. That magical USB SoundBlaster adapter loses connection randomly, or just won’t connect at all. I suspect too that the SoundBlaster may also be the source of a lot of the FM transmitter woes that some have reported. USB operates a lot closer to radio frequencies than audio, and there is that pesky USB wire (antenna?) that’s part of the thing. So- both of these “myths” are likely connected.

In fairness I will say that the FM audio in my video was slightly distorted on the low end. It turns out the volume out on my FPP Show Runner somehow got reset to 80. The sweet spot for my transmitter is setting the output volume for the R-Pi to 70.

So the bottom line: If someone insists that you HAVE to do something a certain way in this hobby, take it as advice but not a “must” and certainly not a rule*. There are a lot of people in this hobby that consider themselves “experts”, and while they have a lot of experience and may have been doing shows for 10+ years, they can only really speak from their own experience. In my own non-expert experience- there are a lot of things that work just fine, even though they aren’t supposed to.

*Okay, some actually are rules. Like you really NEED to use GFCI outlets for the AC power for your show. You also really need to use fuses, proper wire sizes, and proper craftsmanship for electrical safety.

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