[SoundStage!]Feature Article
November 1998

Screw the Spade Lug!

by Doug Schneider

frustman.gif (3829 bytes)High-end audio has grown. Speakers are bigger than ever, amplifiers are heavier than ever, and with the proliferation of separates and tweaks we now have more boxes full of power supplies, line conditioners, and what have you than we ever had before. The complexity of even an average system is increasing and with it comes a host of other issues. Quite surprisingly, though, I CAN live with the lifting, heaving, lugging, and careful placement of all my treasured pieces -- that doesn’t bother me. But, like many things, it’s the little things that count. Or, in this case, it’s the little things that make you mad.

The lowly spade lug -- that little chunk of metal that terminates most people’s speaker wire -- is just such a device. So small, so inconspicuous, so rudimentary, it should not be a problem at all -- but it is. And it is not a minor problem either. Frankly, I’d like to see the spade lug termination terminated, for some very good reasons.

People have whined and sniveled for years about the RCA plug on interconnects as being a lousy connector. I won't vouch that it is the greatest connector in terms of passing electrical signals, but I do know that it at least stays put when attached. You simply slide it on and that’s that. In the case of locking RCAs, crank them down tight enough and you can practically swing your equipment around by its wires (although I wouldn’t recommend trying this). With decent RCA plugs you don't have to worry about them accidentally falling off. Unfortunately, you can’t say the same for the spade lug. In the words of Paul Simon, spade lugs like nothing better than to go slip slidin’ away.

The large metal-to-metal surface contact of spade lug to speaker binding posts may be great for electrical contact between your amp and your speakers, but it does not do much for holding speaker wire in place that seems to have a life of its own. This does not even take into account the heavy network boxes and such on some cables that require extraordinary measures just to set up in a system. It’s obvious when you look at the design of the spade, with its open-top U shape, that concerns about keeping the connection from detaching itself from the post were not considered.

Size matters

The problem with spades slipping off is compounded by the size and stiffness of some of today's speaker wires. Skillfully snaking massive speaker cables so that the spade lugs actually align perfectly with the binding posts requires more patience than waiting for Microsoft to fix all of the bugs in their operating systems. Actually connecting the stiff, unwieldy buggers is the audio equivalent of wrestling an alligator. For example, once you have your spade lugs in place on the binding posts you have to grab the cable by its throat, force it down hard one last time and quickly crank the connectors closed before it escapes. If you’re lucky to get the wires into place, you practically have to stop breathing because any amount of movement in the room will likely jiggle it free faster than Donald Trump can get out of a pre-nuptial agreement. If your dog or cat goes walking by, watch out. The sparks may fly if the wires suddenly shake free.

Hear no evil, see no evil

And why do I see this spade connector issue as a problem? After all, to some people cable wrestling is nothing more than good exercise for listening-chair-loving audiophiles whose daily workout regime consists of nothing more than multiple finger pressing to get CDs in and out of cases and onto transport drawers. Well, it is a problem when your cables flip loose and decide to rub their spade-clad ends together in their new-found freedom and joy. In turn, their happiness turns into causing cardiac arrest for your amplifier. In short, they can short, and this can be dangerous for your high-price amplifier. Do you think that you will find pity from a manufacturer if it happens to you? Not likely.

The problem is so real that it has happened to me many times, and luckily it hasn't yet been fatal. For example, just the other week I flicked on my system, started playing a disc and heard sound from only one speaker.

That's weird, I thought. Everything looks all right.

Then I took a look very closely around the back. One connector had slipped off its post and was within a millimeter of touching the other connector and post! I held my breath and quickly hit the power switch as I sighed in relief that spades didn't short. Right then I'd had enough of spade lugs to convince me to write this article.


I know that there are alternatives.

"Use banana connectors," you say.

"They suck," I respond.

Well, for the most part they suck. Admittedly, there are a couple of good ones, but you don’t see them often. The WBT bananas that expand when inserted are nice, but you pay a small fortune for them. Nordost seems to be doing a fine job with the banana-type method in which they terminate their cables. But if you don’t have Nordost cables, you’re out of luck.

The problem with most regular banana connectors is that although they do initially arrive in your system and form a nice tight connection, it only lasts for a while. Start swapping cables numerous times and that tight fit becomes a snug fit, and in turn that snug fit turns looser than groupies at a Kiss concert. The banana, although admirable, is not the be-all solution I'm looking for. As a matter of fact, some bananas are so bad that you may find yourself looking for, gasp, spade connectors. There has to be something better.

Things that work -- almost

There are some binding posts that almost compensate for the spade lug's shortcomings. The best implementation of spade binding posts that I’ve seen was on my Classé Fifteen amplifier. For these amps, Classé used a simple, elegant approach -- a large hex bolt. Then they supplied a hex wrench that allowed you to grab the cable by the neck, jam it against the post and squish it death with a tight turn of the wrench. You could torque it really hard too (although they would strip if you weren't careful). It was pretty good and it withstood a moderate amount of torque before it loosened up -- far better than most binding posts.

There are other good examples too. Cardas makes a nice binding post that you can really crank down on. These are about the best I have seen in recent years and many fine amplifiers, like my Blue Circle BC2s, come standard with them. Still, it shouldn't be solely up to the binding posts to solve all of the problems when there are better ways.

There is a solution

Instead, why not fix the spade lug itself? Why not ensure that even if the spade connector comes loose, the cable will stay on the binding post and not chance it hitting and shorting against another post? It’s simple safety.

The solution I would like to see adopted is backward compatible and will work with most of the binding posts today where the nut of the post completely unscrews. Perhaps someone's already got what I’m after. I would like to know because I would surely ask for my speaker wires to be terminated with them.

What needs to change is the spade itself. and the change is simple. Instead of making the spade in the shape of a U, make it in the shape of an O. A ring connector! A ring will never come off the post even if the nut of the post is very loose. It would essentially be locked on. The installation of cables would be simpler too. Simply unscrew the binding-post nut, place the O-ring spade connector over the post itself and screw the nut back down. Easy.

Connecting large, unwieldy speaker cables becomes a snap. No longer do you have to force the positive and negative leads simultaneously down on their respective posts like you are trying to drown them. Just slide them over the posts and they’ll hold there by themselves while you grab a tool to tighten them down.


I think so.


You betcha!

Now someone GO DO IT!


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