If you've been involved in audio for any length of time you've probably come up against a problem that could only be solved by using an adapter. Sometimes it's merely a matter of going from a balanced audio cable to single-ended termination. But even this relatively simple conversion can have you emptying the contents of every drawer that might, even on an off chance, contain the right piece of conversion hardware.
Recently I received a pair of speakers that used a conversion/EQ box that only accepted RCA single-ended cables. The system I wanted to put the speakers into used balanced XLR-terminated cabling between the preamp and the power amplifier, so I needed to find a pair of balanced female to RCA adapters (it didn't really mater if they were male or female.) I could have replaced the entire 25-foot run of balanced XLR-terminated Cardas Clear cable with a single-ended RCA terminated cable, but it would have been from a different manufacturer, and require some "settling-in" time before I could begin serious listening, so I decided to go the adapter route. Exit left, downstairs to my "shipping room" where I keep all my cables and adapters.
After spending close to ½ hour going through all the places where a one-piece female XLR to RCA might be located, I came to the well-founded conclusion that I did not own such an adapter. Time to shift into McGiver mode. What I did find during my search was an adapter from female balanced XLR to male ¼" phone plug. The next thing I found were two adapters that went from female ¼" phone plug to male single-ended RCA. Eureka! After uniting the two adapters I had a 5" long hunk-o-metal that needed a support underneath to keep it from pulling the little EQ box off the shelf. But it worked with no added hum or noise.
If I had the time, money, and inclination, a better, more audiophile-approved option would have been to have a custom adapter made by a firm such as Drew Baird's Moon Audio, who specialize in fabricating made-to-order cabling and adapters. This is a far less expensive solution than keeping a 25-foot run of single-ended Cardas Clear around, just in case.
About a month back I resorted to Moon Audio for an adapter that allowed me to use headphones that were terminated with two full-sized Balanced XLR connectors with a headphone amplifier that had a single 4-pin balanced XLR termination. For $90 Moon Audio made a ½ meter-long adapter using the Blue Dragon V3 cable and Neutrik termination hardware at both ends. I've got to say it sure beat trying to home-brew my own adapter.
If you're like me, and switch components in and out on a regular basis, you're probably going to come up against a situation that requires adapters. Acquiring the ones you will most likely need BEFORE you need them isn't the worst idea in the world. Because, when Murphy's Law exerts it not-so-subtle influence on your audio world (inevitably when you do need an adapter it's usually on a Friday afternoon, going into a long weekend) the Cosmos will always reward "the child who's got his own" especially when it comes to adapters.