Analog Led Strips.
These are the 12V led strips that all light up at the same time.
They are fairly easy to use with lightshowpi. First thing you need to know is it will require a little more hardware then just your RPI and the strips. If you look at this link it will show you the basic setup you need.https://learn.adafruit.com/rgb-led-strips/usage
Each strip requires 3 pin on your RPI plus a ground.
You also need to use an external 12V power supply and that needs to share a ground with the RPI.
Also one long strip is not going to look that good. What I suggest is to use several smaller strips all on separate channels. It requires more mosfets and wiring but the results will be a whole lot better.
As an example
1 X 5Meter roll will need 3 gpio pins, 3 mosfets, a separate power supply, some hookup wire, and some perfboard to solder it all up on.
You can use a breadboad for testing, but it really needs to be soldered when you go to use it in your show.
But a 3 channel show does not look that good, so if you take 5 X 5Meter rolls of these strips you will need 15 gpio pins on your RPI, 15 mosfets, 5 X 12V power supplies or 1 really big one then you have a good show. But it takes more work and parts.
Your thinking 5 strips is a little spars for your show, no worries. This same setup will work with expansion chips like the MCP23X17's. But remember you still need the mosfet and you need to solder it all up.
Now on the software side you do not need to make any changes.
But in your configs I have some advice.
Everything needs to be in pwm mode, that is the default so no need to change it.
I played with the pwm range and found that 100 worked really well.
Custom channel frequencies were very useful, I only had 1 strip hooked up, but it helped me get a look that I liked.
You set the gpio pin up the same way, just remember you are using groups of 3.
And speaking of gpio pin, you might want to change the way that you connect them to the RPI. You could just go in order 0,1,2 for the rgb of the first strip, and so one for the rest. But you could also mix it up and put all the blue at one end, red in the middle and green at the end
You could hook the wires up that way, or just change the order you list them in the config file
gpio_pins = 0,1,2,3,4,5
gpio_pins = 0,3,1,4.2,5
You will want to play with this, and for the gpio_pins setting as long as you keep the same number of pin you will not need to re-cache your songs between change. Changing custom_channel_frequencies you will need to re-cache your songs.
One other big note. On first play it will not look so good (mostly white), but after a sync file gets generated then you will have a much better looking show, lots of colors.
Song choice is something to test also, the tempo and intensity make a big difference.
Another thing to conciser is to use smd3528's instead of the 5050's
With the 5050's each led is a single rgb led and the entire strip is lit to that color at the same time. With the 3528's each led is one color, the first is red, the second is green, the third is blue, and then it starts over again for the rest of the strip. While you can't mix colors and get violets, pinks, and yellows, you do get a nice looking show and it's a little more predictable.
Something else to mention, you can still use your relay boards with your regular Christmas light hook up to them. And you can have them in pwm or on/off modes, you just need to specify them in the config under pwm_modes.
mosfets 3 for each strip
soldering is a must breadboards are okay for testing, but they will not hold there connections over time. I had some loose connections at first, worked fine for --state=fade, but when I ran the show not so much.
common ground you need to tie them all together or they will not work
external power for the strips, make sure you have enough Amps for your strips. And never, ever, never, (did I say NEVER) connect 12V to your RPI.
expansion chips they work, but again you need to solder things together to make them work right and work right all the time.
gpio_pins groups of 3 and play with the order, the more channels use the better things look. Using your relay boards and adding other light works too.
pwm_range I found that 100 looked good with what I had, but play with it you might like a higher number (makes the lights brighter, but also they vary less), or a lower number (makes the lights dimmer),
custom_channel_frequencies you don't need to use this one, it's a pain as you have to keep re-caching the songs, but if you have the patience you can fine tune things.