coronavirus - killing shows

So not only am I not going to TPF, but also not MGC (which means I'm not bringing van halen out anytime soon).  I'm still planning on bringing it to Chicago Expo but that's still 7 months away.

Because I have so much time I'm not going to waste it.  I'm going to try to finish all the basic things I was going to do (IEC connection, try to move more of the boards into the lower cabinet for each hookup, move the audio amp near the coin door for easy volume control), but I have a couple stretch goals in mind:

1. While the speakers are decent, they are by no means optimized.  I literally shoved a couple speakers inside a poorly crafted wooden box and drill some holes on the front.  I would like to get a pair of the 3d printed ported speakers made up to put behind the 80s boombox fascade.

2. I love building LCD mods, and I think adding one that plays music videos would be a nice attraction.  Since there is effectively zero space between the top of the playfield and glass, I would probably have to make some sort of topper.

You see... IEC

One thing that really bothers me about early solid state, the crappy way they did the plug.  It comes up from the cabinet, goes up through the hole, then you have to get it in that channel just right so the backbox doesn't pinch it.  Or you FORGET to do that, bolt down the backbox, and go "CRAP! I forgot the linecord!"  Well screw that.. I'm installing an IEC connector on the back, because I can.  Got out my multimeter and set it to continuity to check which pins are which.  Looks like the back of the IEC connector directly correlates to a standard plug.  Got the port installed by drilling some holes and opening it up with a jigsaw, now I just have to solder the old linecord to the IEC connector and I'm all set.

Van Halen is coming to MGC

So I've committed to Ed Owens that I'm bringing this game to the show.  The homebrew section at both Midwest Gaming Classic and Chicago Expo are fantastic and I want to be a part of that.  Big thanks to Hugh Spahr for rebuilding the SD card from scratch since the original got corrupted (and neither of us made a backup).  He got it to work with a pi zero which makes it look even more impressive in the backbox.

So beyond cleaning it up (polishing the playfield, trying my best to get rid of corrosion on metal), I also wanted to make some improvements.  This isn't a knock on Hugh, I know he worked really hard to get this done for Pintastic and it's amazing he was able to do all this himself.

I decaled the spinner and shooter plate:



I also wanted the backglass to have more light, so I created a new wood panel that just clears the LCD and dropped more strips along the sides.  I also didn't like the screw to hold down the light panel so I put the screw in backwards and tightened it down with a wingnut.  There are some hotspots and I tried defusing them using a ceiling tile panel, but it ended up texturing the light in a weird way.. Plus ceiling tiles are made from acrylic and they crack very easily.

new year, when's the reboot?

So before I jump in, I need to clear some things.  My Sega twister sold, gotta admit it's weird to have an empty spot now.  My goal is to try to get some of my other existing pins working (most importantly finally get a vacuum formed ramp made for back to the future), which means I'm probably going to drag that out of the basement so I can adjust my 3d printed prototype before kicking off tooling.  I'm thinking about getting a quote from a couple chinese companies because it'll likely be at least half the cost of domestic costs ($3k tooling, $100 each piece).


I'm going to try to keep a spot open to keep the homebrew upstairs.  I do have an idea for a cabinet that saves floorspace.

Ported enclosure... WORKS!

So 20 hours later and a little assembly and I've got a kicking speaker.  My little 2" speakers I use on my computer are pretty loud and a little bassy, but nothing like this.  I'm so happy with the results that I published it on thingiverse so anyone can make one:
https://www.thingiverse.com/thing:3912736

Video showing the speaker vibrating
https://youtu.be/waviRdexpMg

speakers came

So my initial impression of the 3" speakers I bought.. even without an enclosure equally or better than the bookshelf speakers I use on my computer.  I hooked up the same amp I use for my computer to one of the bare speakers and it was quite loud and good sound.  I put it in a cup so it has some back pressure, cranked down the treble a bit and the speaker definitely moves quite a bit when it has some bass thrown at it.  I'm going to try to 3d print at least one enclosure this weekend to see if it makes a big difference in the sound.  I'm almost wishing I had bought a 3rd to turn one into a bass only speaker (the LEPY amp is a 2.1 channel so it does have a bass output on it).  I might try it in each output to see if there's any difference.

I've grown up always thinking bigger is better (and if you want true air moving bass in a car that's still true), but for a pinball I think even small speakers can deliver pretty good sound if they are enclosed properly.  We shall see.

speakers ordered

So after watching this video of a 1.5" speaker putting out crazy sound by 3d printing a fluted enclosure: https://youtu.be/uujaBjf3Uwg

And this video using a 3" speaker and a 3d printed case:
https://youtu.be/4_4tu4rAtgI

I decided to order a pair of these mid-range speakers: https://www.parts-express.com/grs-3fr-4-full-range-3-speaker-driver-4-ohm--292-436

And I'm going to design my own enclosure from scratch.  I know ideally there is math and calculations for optimizing sound, but I believe that this design in general helps to direct the airflow and allow the soundwaves to bounce around to increase volume and waveform range.  Look at any bose speaker, they all use this design.

Right now the main case above is an 18 hour print job each.  I'm going to add threaded brass inserts where the holes are, and 3d print sides to close it all up.  I may add some channel features to really seal everything up.