Why are there so many DC barrel connectors?

[MarkOne]

Why? World? Why?

And how are you supposed to figure out which one to get when you can’t get the vernier gauge inside the bloomin’ hole or on the pin of the socket?

Grrrr!

[Hugh Robjohns]

They are all 'standard'...

[Folderol]

They are all 'standard'...

... just not the same standard.

[N i g e l]

"the great thing about standards is that there are so many to choose from"

+1 for hating the connectors when they need replaced or trying to find a replacement PSU with the correct connector on it.

I use a vernier & a plastic template with various sized holes and things to poke into the center, that can then be measured.

The only thing worse than measuring barrel plugs is barrel sockets - trying to measure the pin in the middle.

[Drew Stephenson]

The only thing worse than measuring barrel plugs is barrel sockets - trying to measure the pin in the middle.

This ^^^

[The Elf]

Fabulous things these external PSUs. Glad so many people feel they're the better option...

[Drew Stephenson]

Ha! How long have you been waiting for that?

[ef37a]

This is why I never throw rats away and even if they are faulty I cut the power plug off them, leaving about 300mm and chuck it in a draw. Never know when you will need to splice one onto an existing PSU to get you out of a hole.

But, to answer the question, as with phones, every manufacturer wanted you to buy his supply in the event the original failed and a great deal of gear came with (and still does in many cases) dire warnings that on no account should ANY other supply be used!
In truth of course, so long as a supply meets the voltage and current requirements and is the correct polarity, brand matters diddly.

I would love to know when the co-ax power connector came on the scene? Early portable kit, cassette recorders, calculators e.g. used a 3.5mm jack. I have an old compressor pedal so equipped.

Dave.

[MarkOne]

I have an Alesis mixer that gets used sometimes for smaller live gigs and that has a 4 pin screw collar aircraft style connector. Brilliant, it's very easily identified, and the screw collar makes it secure from the potential of being yanked out during the gig.

I know these connectors are probably a bit more expensive but we are talking PRO audio gear here (The unit that made me raise this question is a Roland synth), not some 20 quid problem solver from Amazon, so if we have to have external PSUs on pro gear, (and I understand the arguments for that) at least make the connectors a bit professional too.

[jjlonbass]

Barrel connectors have been around a long time, most likely since the '60s. I had an ITT radio that was first released in 1972 that had a barrel socket to connect to a "battery eliminator".

John

[The Elf]

I have an Alesis mixer that gets used sometimes for smaller live gigs and that has a 4 pin screw collar aircraft style connector. Brilliant, it's very easily identified, and the screw collar makes it secure from the potential of being yanked out during the gig.

But I hope you carry a spare. Finding one of those at a gig is going to be a tough one.

I don't mind a power connector being capable of being yanked out - at the extreme it's better that than the whole thing crashing crashing stage-ward, or something snapping.

[adamburgess]

I have a box full of the jack ends of the cables. I say, 'luckily', but the breaks always luckily seem to be at the heavy transformer end - so I just keep the LV ends.

Recently, I've started powering the few bits of 12V stuff I have with inline CCTV 12V 5A adapters from Amazon with an IEC in. I just lop the end off and solder on an appropriate sized jack if it doesn't fit, or has reversed polarity. Maybe not the best quality, but then, neither are the ones that come with the gear. But, these 5A ones definitely seem beefier and more roadworthy. And lots of space to write a label if they're reversed, or have a stupid sized connector on, or what it's actually for…

And, Korg (example only!) has 'about' three 'standard' jack sizes just in front of me. Grrrr! Sennheiser seem to use a couple of slightly different sizes, too.

Going back to the OP, why!?!?! Haha

[MarkOne]

Recently, I've started powering the few bits of 12V stuff I have with inline CCTV 12V 5A adapters from Amazon with an IEC in. ...

This is a brilliant idea! Consider it well and truly nicked!

Also while we are on the subject of these supplies...

Manufacturers, if you really have to supply your kit with the PSU built into the mains plug, can't you all just DECIDE WHCH FRIKIN END OF THE PLUG THE ELECTRONICS IS IN AND AGREE ON IT! half of them put it above the plug and half of them below. Hint, they won't all fit in a rack supply strip unless you waste a couple of U above or below.

[ef37a]

Recently, I've started powering the few bits of 12V stuff I have with inline CCTV 12V 5A adapters from Amazon with an IEC in. ...

This is a brilliant idea! Consider it well and truly nicked!

Also while we are on the subject of these supplies...

Manufacturers, if you really have to supply your kit with the PSU built into the mains plug, can't you all just DECIDE WHCH FRIKIN END OF THE PLUG THE ELECTRONICS IS IN AND AGREE ON IT! half of them put it above the plug and half of them below. Hint, they won't all fit in a rack supply strip unless you waste a couple of U above or below.

Agreed but I would like to see the end of the WALL rat except for very low power situations.
Line lumps IMHO should have a fig 8 mains input (600W+ from 230V nom') and a co ax power SOCKET and be supplied with the appropriate leads for the country.
THE most common cause of failure of PSUs is the cable cracking at one or other entry point to the 'lump'. It then has to be consigned to the WEEE bin but is of course still a worker.

I have cracked them open in the past and rewired them (you need a BIG mother vice!) but 'don't YOU try that at home folks!

Dave.

[adamburgess]

Recently, I've started powering the few bits of 12V stuff I have with inline CCTV 12V 5A adapters from Amazon with an IEC in. ...

This is a brilliant idea! Consider it well and truly nicked!

Also while we are on the subject of these supplies...

Manufacturers, if you really have to supply your kit with the PSU built into the mains plug, can't you all just DECIDE WHCH FRIKIN END OF THE PLUG THE ELECTRONICS IS IN AND AGREE ON IT! half of them put it above the plug and half of them below. Hint, they won't all fit in a rack supply strip unless you waste a couple of U above or below.

One good thing about having 5 amps to go around, is that one adapter can do a few bits of stuff. Built my singer a rack for her solo gigs - an XR18 on an IEC then 3x Sennheiser RX and a wireless access point all from the same DC supply. Been working for over a year and all she has to do is one PowerCon. The 240V inside is in a Wago box tucked to one side of the mixer. The DC connections are all exactly the right length, and if something really went wrong, she still has the original adapters (two different types, btw) in the car with spare XLRs and batteries etc.

[The Elf]

Recently, I've started powering the few bits of 12V stuff I have with inline CCTV 12V 5A adapters...

That's an intriguing idea. Do they do a 9V version as I'm sure more people would find that useful?

[adamburgess]

I'm sure they will do a 9V version. Usual thing, lots of the same product under different names.

Saved a bunch of space in my 'studio' desk at home and for a few live racks for myself and a couple of others I've put together.

[The Elf]

Neat.

As you know, I mostly get my live gear modded, but there are a few bits of gear that have to be PSU-ed (e.g. USB hubs, IEM transmitter, etc), and that could be a future solution.

Thanks!

[adamburgess]

Still looking on the UK's Amazon site (I'm in the UAE). 12V seems a lot more prevalent than 9V, but with a few devices hanging off the end, I'd risk a bit voltage drop and sending 10.5V to a 9V device, to be honest.

[MarkOne]

Just to throw another joker in, Roland have decided to make the pin negative and the barrel positive. And some quick research shows me that both that and Barrel Negative (which would seem logical to me) are equally prevalent. So that's another wholly unstandardised element to the already chaotic barrel connector farce.

I do wonder how this actually evolved and why there ended up being so much divergence.