About McCullough's Chime Units


Dear Fellow Pinball Collector, 

As an avid American pinball collector of over 30 years who relocated to Germany about 12 years ago, I was surprised to get my first "German" pinball machine home to find it had no chimes. Thinking it was just a fluke I continued to add to the collection and every time, the mysterious missing chime unit eluded each new conquest. To this day I still have not figured why the chimes were never included in these machines... noise ordnances? ... Germans did not like them?.... All I knew is I had to get all these machines fitted with chimes if I was ever to recapture the arcade glory days of my youth. After a year of fruitless searches on pinball parts supplier websites, eBay and the Mr. Pinball Classified's I knew the only way I was going to get chimes in my machines was to make them myself. And so started my quest into the world of chimes. After six months of weekends and evenings researching the Internet, rummaging local material suppliers and hardware shops and a crash course in mechanical engineering from my father, a mechanical engineer of over 40 years, my first prototype was done. The chimes worked and they actually sounded ok but there was still room for improvement. Another three months of tinkering with the design, adjusting the power of the coils, trying out an array of materials for the grommet and finding the true "vibration nodes" of each chime to maximize their sound quality and finally I had a chime unit that was pretty much as good as the originals. The next stage of the project was to develop jigs and other manufacturing processes that would allow me to make a small batch of chime units for the rest fo my collection relatively quickly. I didn't want to spend months worth of weekends per chime unit. I also wanted some time to actually play my machines! After successfully making a batch of chime units to equip my collection I figured that would be that. I would just make a batch now and then as was needed for my own collection. But that was soon to change. Much to my surprise I was not alone in my quest for a chime unit. As word got around that "there was this American guy in Germany who makes chime units", I was getting approached by more and more collectors asking me if they could buy them and a lot of them encouraging me to sell them on-line. And so www.chimeunit.com was born and the idea of making them available to other pinball collectors who were unlucky enough to have picked up a pinball machine without a chime unit. 

And now a little to the chime unit itself. The chime unit is a "hybrid design" that will fit into almost any electromechanical pinball machine. Almost all parts including coils, chimes, solenoid plungers and chime housing are handmade by me. One of the major goals of this design was to make a chime unit that remained affordable and something that could be made from readily available materials. In most cases a particular needed part just did not exist or if there were existing parts, added so much to the cost that the unit would be cost prohibitive to make for my collection. As such most of the parts used on this unit are not exchangeable with chime units made by any of the pinball manufacturers. The overall chime housing and brackets are of a lighter gauge metal than traditional units to keep costs down but hold up just fine even after extensive home use. The chime unit does not have the traditional amplification box. After much experimentation I found the same effect could be achieved by slightly increasing the power of the solenoid coils, thus reducing cost and complexity. In the traditional chime units that were designed to take extreme use and abuse, several manufacturers decided on using a super low power coils that could take continual use all day long without overheating and burning out. To compensate they added a hollow box with chambers that were tuned to the same frequency as the chimes. When a chime is struck the sound resonates in the chamber and amplified the sound much like the hollow body of a guitar does. As pinball machines in collectors' hands rarely ever see the kind of abuse some of these machines got in the arcades using a slightly more powerful coil instead of an amplification box made the most sense. 

So enjoy the sound of chimes again as you, like I, work to keep the pinball dream alive buzzing, ringing and chiming away in your basement, garage, den or wherever your pinball adventure takes you. Feel free to contact me with your comments, concerns, questions regarding the chime units or pinball in general. 


Mike McCullough