Pin 1 Problem revisted

While not directed related to audio measurements, a Pin 1 Problem is something worth mentioning every once in a while since it still plagues the professional audio industry and many still don’t know about it but suffer the consequences.
More than 15 years ago, I was introduced to the concept of a “Pin 1 Problem” on a user list by Jim Brown. At the time I realized that Pin 1 Problems were a serious issue and while some manufactures addressed it immediately once the solution was explained, others ignored the matter and have kept on designing gear with a pin 1 problem. Consequently, I create this website as a place to gather and share information about pin 1 problems:
If you want to understand what a Pin 1 Problem is and how it can affect your audio, read this recent article by Jim Brown: – Pin 1 Revisted by Jim Brown page 1 – Pin 1 Revisted by Jim Brown page 2 – Pin 1 Revisted by Jim Brown page 3
This is the original document that Jim Brown is referring to: – Pin 1 Revisted PDF
A “Hummer” is a device meant to help find Pin 1 Problems. It’s parts, construction and use are explained in this PDF:
Build a “Hummer” to help find “Pin 1” ground problems PDF
I intend to test all of my gear for Pin 1 Problems soon and share my discoveries but before I go to the trouble of building a Hummer, I thought I would verify that it is still the appropriate device to test modern equipment for a pin 1 problem. I’ll report back once I’ve heard back from my friend and expert on the subject, Bill Whitlock of Jensen Transformers.