I'd buy a set of the correct rubbers from Pinball resource. They do the job perfectly and I've tried many other ways but I come back to using theirs. I just fitted a set to a Spirit of 76 which had playfield rubbers and sounded terrible, and after the new rubber kit they sounded fine.

Chime rebuild kit from PBR will do you just fine. No one makes the bars anymore though I'm sure you could cut some at any hardware store, but that's extremely unlikely you'd need those. Coil sleeves and stops and grommets, all in that kit IIRC. If that white plastic tub is cracked or broken you won't get the volume, it's a sound chamber (same idea as acoustic guitars) so might need to replace that but judging from the pic I'd say the kit should sort you. I don't know about Williams but I've rebuilt a Bally and a Gottlieb and they sound very different. The Gottlieb is more musical but the Bally was significantly louder.

You will never get the kind of sound out of Williams chimes that you do out of Williams bells.

I've rebuilt a lot of them and this statement is the total truth. There's no way to make them sound as good. It's the design and the sound box that make the difference.

If you can find one, put a Gottlieb box in the Williams game and it will be better than anything you can do with a Williams box.

Bally boxes aren't bad, better than Williams, but on this one, Gottlieb wins hands down.

I just rebuilt my Gottlieb unit and it sounds good. I'm not sure how loose or tight the nuts holding the bars in should be. I left some play, but not a lot. Is there a specific way to adjust these?

I have read that Chicago Coin used a doorbell chime design

Doesn't seem like it, unless you mean a chime unit similar to later Gottlieb and Williams games.
Here's a picture of the chime unit in a 1976 Chicago Coin "Sound Stage"
http://ipdb.org/showpic.pl?id=2243&picno=36217

Here's a pic from the 1966 "Hula Hula"
http://ipdb.org/showpic.pl?id=6324&picno=66860&zoom=1

Here's a pic from the 1956 "Blondie"
http://ipdb.org/showpic.pl?id=321&picno=36443&zoom=1

While we’re in this topic, how loose or tight do you like the bars on your Gottlieb chime units? Just curious how they were factory. I vary mine from game to game a bit but haven’t landed on a sound where I say “that’s it!”

Just curious what others do.

I snug the lock nuts down just to the point of touching the top of the Gottlieb rubber grommet. But not down to start squishing the grommet which reduces volume and continued resonance.

If you leave the nut up above the grommet, you may get a bit of excess rattle of the bars.

I thought I'd post in this thread as it's kind of related and I didn't get much response when I started a specific thread on it.
The screw that goes through one of the chime bars (on my Bally Boomerang) has snapped off. See pic. Does anyone know where I can get a replacement assy (it looks like it's part number A-3293 from the Bally parts manual)? Not sure what to do if I can't find one.
This is actually a friend's machine I've been babysitting and I'd really like to get it working before I return it. Any help appreciated!

Boomerang chimes (resized).jpg

I'm sure you tried this forum?
https://pinside.com/pinball/forum/topic/the-em-seeking-parts-thread

Shouldn't be too hard to fix drill it out and go to the local hardware store and get a bolt and a nut that should fix it good luck.
Raff

I recall this being addressed once before, but wouldn't know how to find it. As Raff says though, looks like an easy fix with a good sharp drill and a small nut and bolt.

Got it guys, thanks, I’ll give that a shot

Worked a charm thanks

I have installed Gottlieb chime sets in all my other makes of pins. Gottlieb chimes in my opinion are just the best and really do sound better then any other make. I do recommend buying the grommets and installing new ones if the existing ones show any type of damage. Thats my opinion anyway.

The absolute best sounding chimes I have ever heard were in a Sonic Super Straight.

Chime repair kit from PBR made my Williams chimes sound great. Highly recommended.

Hmmm they look the same as most others but I’ll take your word for it. This will be motivation to get mine working.