A selection of various sockets for banana plugs

In today’s review, I want to show you several types of connectors that, in my opinion, are great for power supplies, electronic loads, and the like, even though they were originally designed for audio equipment.


I’ll start with a warning: since these connectors weren’t originally intended for power supplies and similar equipment, you use them at your own risk. Personally, though, I think most of the options shown are no worse than dedicated connectors—and may even be better in some ways.

I’ll show several options today. Most were ordered from Taobao, one is from AliExpress, one from Banggood, and one was bought locally.
But first, what are we talking about?

You often see connectors on the front panels of power supplies and electronic loads for connecting devices under test and, accordingly, power sources. Most people use whatever they have on hand, or connectors specifically made for the job. The first approach doesn’t always give you a good result; with the second, you can’t always find the connectors for sale. For example, I’ve never seen the wire clamps shown in the second photo for sale, although “clamps” is probably the more accurate term.



I’ll provide links to most of the products as I go.
As usual, the items from Taobao arrived in separate little bags. I’d planned to review the AliExpress connectors separately, but decided to combine everything to keep things simple.


First, here’s a group photo. The top row has the small ones from Banggood, the larger ones bought locally, and the third type from AliExpress. The bottom row is from Taobao.


Weight is the first thing you notice when you pick them up. Obviously, the more metal, the heavier they are. I didn’t weigh the smallest ones, but the larger ones definitely inspire confidence: the set weighs around 80–90 grams.
A note about the set: these connectors are usually sold individually, but people generally order an even number, and sellers ship them in pairs—one black and one red. This is an important difference from dedicated connectors, which come in other colors besides red and black (or white). Unfortunately, these are only available in two colors.


I’ll start with the cheapest ones. To save time, I’ll show both types I have at once.
The small ones are from Banggood; I bought them for a review of a small power supply, but they’re really tiny. The second type is a bit larger. I bought them locally for about 20 cents each; on Taobao, they sell for 6–7 cents.


1. The small ones don’t have a socket for a banana plug, unless you drill a hole.
2. Neither type has a hole for clamping the wire, which is very inconvenient. Actually, I only realized how inconvenient it was after using the ones that do have one.
3. The nut or clamp: it’s hard to say with the small ones, but the larger ones are absolute junk. The threaded part is soldered in place, but when you try to clamp a wire, it gradually gets pushed out. In the end, I had to fit washers on my electronic load that were slightly larger than the screw diameter but slightly smaller than the diameter of the threaded sleeve.
Also, some of these connectors have badly formed threads, so you have to “work them in” first.
4. The wire is connected by clamping it between the two supplied nuts and washers.


I’ve used the larger connectors in almost all my devices, but I’ll gradually replace them with better ones.


You’ve probably seen these connectors on various audio devices. I didn’t know they came in three sizes, though—I’d only used the medium ones. In product photos showing them on their own, it’s hard to tell the second and third sizes apart; they look that similar.


A note on the design: all three types I have are fairly short, although versions with a long mounting screw are available for installation through a thick panel, such as a sheet of particleboard.
The wires are usually connected with a screw and a tab, or by soldering.


Some designs also have a special recess for the wire, where it’s wrapped around and then soldered in place (I think).


The smallest ones cost $0.27 each (here and below, the price is per unit). Product link.
I bought them as extras to use with the larger ones for four-wire connections.


1. There’s a hole for a plug.
2. There’s also a side hole for a wire, but you can’t connect a plug and a wire at the same time.
3. The nuts seem to be embedded better than in the cheap ones shown above, but it’s hard to say how well they’ll hold up in practice.
4. Wires are connected by soldering.

Dimensions:
Length - 31 mm
Front thread - 6 mm
Rear thread - 6 mm
Front section length - 6 mm
Rear section length - 20 mm (overall), 13 mm (maximum, including the insulator)
Mounting hole - 7 mm
Depth of the hole for the banana plug - 17.5 mm
Side hole - 2.6 mm



The complete set.


The second option costs $0.41, link. Here, these cost around $1–1.2 each.

I've already used these connectors in a couple of electronic loads, and I really like them.




1. There is a hole for the plug.
2. There is a hole for the wire, but it's best not to clamp a thick wire here because the thread is a tight fit.
3. Clamping nut.
4. There are additional flats on the rear section. The wire connects via a solder lug, though the same version is also available for soldering.

Dimensions:
Length - 33 mm
Front thread - 7 mm
Rear thread - 4 mm
Front section length - 11 mm
Rear section length - 14.5 mm (overall), 10 mm (maximum, including the insulator)
Mounting hole - 6.5 mm
Depth of the hole for the banana plug - 15 mm
Side hole - 3.8 mm



A few words about the clamping nut. It's made of two parts: the part that presses against the wire spins freely, so when you tighten it, it doesn't push the wire out (if it's not in the hole) or cut through it. The metal also protrudes slightly, and there's a small recess in the mating part to hold it in place more securely.


The complete set.


The third option costs $0.78, link

It's essentially the same as the second option, just noticeably larger. Almost all the dimensions are scaled up proportionally, so side by side they look the same.



1. There is a hole for the plug.
2. There is a hole for the wire.
3. The clamping nut has the same design, but here there's knurling on the clamping face, and the recess in the “fixed” part is a little larger.
4. The wire connects by soldering. The nut that secures the connector itself is countersunk, so when tightened it presses against the device housing, not the insulator.

Dimensions:
Length - 46 mm
Front thread - 8 mm
Rear thread - 8 mm
Front section length - 16 mm
Rear section length - 22.5 mm (overall), 15 mm (maximum, including the insulator)
Mounting hole - 10 mm
Depth of the hole for the banana plug - 19 mm
Side hole - 4.8 mm



Interestingly, the insulator here consists of three parts (not counting the transparent one), rather than two. Otherwise, it's the same as the previous ones.


These are completely different connectors. They look more substantial, and at 40 grams each, they're impossible to miss.

They're also noticeably more expensive at $1.48 each, link.



1. There are holes for the plug.
2. There are holes for the wire, but there's one small issue: on one connector, the hole shifted during drilling, leaving the side wall quite thin. It's not critical—the metal is still thick enough—but it looks sloppy.
3. The clamping nut doesn't come all the way off, and that's intentional here. It's actually quite convenient: it turns easily but doesn't fall off. As with the previous two, the clamping section consists of two parts, one of which spins freely and doesn't cut the wire. It also has knurling, like the previous ones.
4. The wire can either be soldered or secured with a screw. In my opinion, soldering is more reliable.

Dimensions:
Length - 50 mm
Front thread - 8 mm
Rear thread - 8 mm
Front section length - ?
Rear section length - 22.5 mm (overall), 16 mm (maximum including the insulator)
Mounting hole - 10 mm
Depth of the banana plug socket - 21 mm
Side hole - 5.1 mm



The insulating washers have an extra tab to prevent them from turning in the panel hole. It's hard to see in the photo; it's on the left side of the first washer.


The set.
Everything looks good and is well made, but there's a problem: the outer insulation on the clamping nut is something like heat-shrink tubing, and it got scratched during shipping—or most likely even before it left the seller. So it's now less safe to use :(



These are connectors from AliExpress, the only ones with a specified rating—up to 80 A—and I bought them specifically for a high-power electronic load.

They come as a set of 4, priced at $9.99 per set, link.

These are the most unusual connectors. For starters, the clamping nut has a handle that isn't round. They're also heavy: the set weighs nearly 90 grams. Their overall appearance is clearly different from the previous ones, but the fact that they also come in pairs suggests they're intended for the same kind of use as the previous ones.


1. There is a hole for the plug, but unlike the previous ones, it's in the clamping nut rather than the panel-mount section.
2. There are no holes for the wire. That's a shame; I think one would have been useful.
3. The metal insert in the clamping nut protrudes slightly and is firmly embedded. The handle material is also different from the previous ones; it's clearly denser.
4. The insulating nuts have a hexagonal recess for the metal part, so it sits slightly recessed. The threaded section is plain steel, with no gold-colored finish. The wire is secured with ordinary nuts; I'm not sure it can be soldered.

Dimensions:
Length - 60 mm
Front thread - 8 mm
Rear thread - 8 mm
Front section length - 8.5 mm
Rear section length - 29 mm (overall), 19 mm (maximum including the insulator)
Mounting hole - 11.5 mm
Depth of the banana plug socket - 18 mm



The set as a whole. It's hard to see in the photo, but each insulator has two pins to keep it from turning in the panel hole. The overall look is pretty impressive, too.


To sum up, I liked all the connectors/clamps I bought, but the largest ones from the “trio” and the last ones stood out in particular. The small and medium ones from the same “trio” are also useful for currents up to 10 A for the small ones and 30–40 A for the larger ones (tested at 40 A). But the small ones are pretty basic, and I've seen the medium ones before.
The version with black clamping nuts is decent, but its insulation may make it unsuitable for some applications because of the reduced safety. Still, the double clamping nut design is interesting: the clamping section rotates freely, so it doesn't cut into the wire when tightened or push it out if it's simply wrapped around the threaded section.
As for the first pair, they're ordinary, inexpensive connectors. They're perfectly usable too, but only in non-critical applications or with some limitations.

That's all from me. I hope you found this useful.