I use the Monster Cable Z2 bi-wire for my speakers and this system allows you to have a variety of connections via Monster Lock. I recently moved from Banana clips to spades as I didn't want the connections to my amp and speakers to keep coming out when I moved equipment. I was just wondering: what do you use in both speaker cable and connections and what has been your experience with speaker cables overall ?
A bare wire connection is the best for sound quality as it places the least amount of material between the amp and cable. However, not all amplifier and speaker connectors - typically five way binding posts - are capable of a gas tight connection and therefore a spade lug makes sense.
Banana plugs were meant to be used for temporary connections and have no place in a high end system. When judging connectors think about the security of the connection and the total area of contact any one connection type offers over another.
If you get the top quality Pomona Electronics GR plugs (the dual banana plug type) they will work well over time. You need jacks that have that spacing of course. By the way, they are called "GR" plugs because they were originated many years ago by a company called General Radio that made test equipment...). To terminate them properly, tin the ends of the wires with solder and then insert and tighten the set screws with an allen wrench. I think that the largest wire they will take is #14, however.
A lot of cheap banana plugs may not make real good electrical contact over time; some speaker manufacturers do not like them, so they put screw terminals on instead of binding posts. Vandersteen is one of those, so I use Audioquest 1/4" gold-plated spade lugs soldered carefully to eight 12-foot lengths of #10 Alpha stranded hookup wire for my speaker cables; not cheap, but excellent.
Whatever you do, remember that copper oxidizes rapidly, and so does nearly everything else but gold, so always tin wire ends with solder before making connections. The best procedure to get good flow is to dip the wire end in a can of rosin flux before soldering; this ensures good flow throughout. Clean off rosin after cooling by brushing with alcohol; cheap vodka is excellent for this.
Without trying to start a riff here, I would suggest "tinning" your heavy guage bare wire ends is not the best idea unless you can afford a solder pot. Even then, tin is not the best conductor, nor is lead. Both are the major components in electrician's solder. Even with silver content solder the extent of the silver is seldom more than 4% total the rest is made up of lower quality metals.
The idea here is dissimilar metals are undesirable in a good connection and it's best to have as few materials in the joint as possible. If your connectors are the typical gold plated posts, you aleady have brass, nickel and a few other things to contend with beneath the gold plating. You can say, "To heck with it, it's already screwed up", or you can try to make the best of the situation.
Yes, solder is obviously used in the construction of equipment, it is indispensable in that application. However, you have a choice when it comes to your own connections. I would favor bare copper or a crimped spade lug in this application. The correct tools for either are inexpensive and easy to use. You can clean the spade when it becomes oxidized or you can strip back the insulation to find clean copper in the bare wire. If you make the connection properly and the connector provides a gas tight connection, you need not concern yourself with oxidation of the connection.
Tinned 14 AWG wire will not compress to make a good large contact area connection as will a spade or bare wire. You will have less contact area with the tinned wire which is less desireable. Certainly, if you do not know how to make a good solder joint when using 10/14 AWG cable and spade lugs, this is highly undesireable since a good crimp is always preferrable to a bad solder joint. If you do not understand how to achieve a good, clean solder joint, a crimp type connection with the spade is IMO preferrable to soldering globs of junk into the cold soldered connection. If you do not understand how to make a good bare wire connection or your connectors do not allow such a connection, use crimp type spade lugs.
Tinning wires is IMO only a second best choice if you know you cannot make a decent connection without strands of wire exposed. But without a soldering pot you'll often expose wire further inside the insulation to oxidation, again not a good choice given all the others. If that's the case, either you need to move the equipment so you can make a better connection, use a crimp type spade lug to provide a large contact surface or get someone else to properly do the job and pay for their tools and ability.
In the end, however, the difference between a well soldered spade and a well crimped spade is largely academic and you are unlikely to hear a significant difference between the two techniques. Use the spade and discard the bananas, they don't belong in a high end system.
It's been my experience that people who say ________ doesn't belong in a high quality system are sticks in the mud. Properly terminated banana clips are fine. Sometimes spade lugs will not fit in the binding post of some very high quality less expensive equipment - or for that matter some very good quality speaker manufacturers don't spend any time at all figuring out the best placement for the post, making fiddling with screwing in spades a big pain in the ass. The best advice is to try both. If the connector isn't of such poor design as to actually change the sound or musical flow, then focus on cost, ergonomics and other very real life concerns. And don't listen to old white guys who say THIS is the way IT must be done to be considered HI-FI!
I was making the assumption that the wire in question was copper wire, which will rapidly oxidize. This tends to imply that there is a need to do something to the wire to prevent said oxidation.
"Tinning", in the terminology technicians generally use, simply refers to coating the wire with solder (high-quality solder being 63% tin/37% lead). I always tin a wire end carefully to insure that all copper strands are fully coated with solder BEFORE I start to solder the wire to a spade lug or some other type of connector.
Yes, a solder pot is a very good idea, but in the absence of same, dipping your wire in rosin flux and applying sufficient heat to get the solder to flow thoroughly onto all surfaces of all strands is quite possible; I have done it many many thousands of times. On the other hand...when I was at Douglas Aircraft in the 1960s I spent many hundreds of hours assembling engineering test equipment from scratch, and as a result I have excellent soldering skills. Not everyone has those skills, and if they don't...that changes the equation a lot.
The problem with simply crimping a connector onto bare copper wire is that this is not a gas-tight connection, which means that the copper will still inevitably oxidize within the crimped area, and copper oxide is not a good conductor of electricity. You are absolutely right, however, when you say that it is better to crimp to a bare wire than a tinned one; crimping is not designed to work properly on a tinned wire. Some companies crimp and then fill the crimped connection area with potting compound or some type of plastic to seal it off from the environment; a person can do this with silicone rubber also.
Interestingly enough, when silver oxidizes, that nasty black silver oxide that forms IS an excellent conductor of electricity! I found that out when I was a microwave technician in the Air National Guard many years ago. A sergeant kept making us clean the oxide off of the silver connectors with polishing compound until our lieutenant, who was an engineer, pointed out that there was no point in it and that eventually we would wear away all of the silver plating...so he said to stop it.
Not everyone has those skills, and if they don't...that changes the equation a lot.
Indeed, my point exactly. If you have no great soldering skills, the worst place to begin would be trying to achieve a good connection between a 10/12 AWG cable and the correctly sized spade lug. That's why terminated cables are more costly. A crimping tool is cheap, effective and virtually anyone can manage its correct operation without any particular skill set. A good crimp connection is easier to accomplish than a good solder connection and nothing is worse than a bad solder connection.
A well crimped connection is "largely" gas tight. Not the ideal but better than most. IMO once you've gone beyond a bare wire connection you are making compromises. Which compromises are acceptable is for the situation and the user to decide. I've opened up crimped connections and screw type terminal blocks that have sat for decades only to find clean copper inside. For the most part in consumer level audio the difference between a soldered and a crimped connection would be not what you hear at first but what you hear in a few months or even years. I would say the decision as to which is type of connection would be appropriate should be based on other concerns such as how do you make a good connection cheaply, consistently and easily.
As I was taught how to make a high quality connection the two major considerations beyond oxidation contamination concerns would be; 1) the similarity of materials at the joint, which does not favor soldered connections, and 2) the amount and security/tightness of the surface area made at the contact point, which leaves out banana plugs as anything other than temporary connectors. But then I am by most standards old and white.
Ha ha ha. Nothing wrong with being old and white. I'm well on my way!
The point is. In audio, as in life, don't be afraid to challenge orthodoxy. A high quality banana connection will make a fine connection. A low quality spade will suffer material quality issue that are likely to affect the sound just as much as a standard banana that you get from Radio Shack. Are spades better? Probably, in some situations, in some systems. Are bare wires the best? Sure, except where they are such an ergonomic pain that they are no longer worth it or where your amplifier will not accept them properly, where they are not. Is a tinned connection better that a crimped connection if the crimped connection has been properly sealed off with shrink wrap, regardless of connector type? Probably not.
Common sense and listening and not being afraid to not do something because it is a pain makes the most sense.
I very much like the discussions on this subject as I am currently restoring several of my vintage stereo systems after sitting in boxes for many years.
My two cents worth. I am a senior electrical engineer at a very large industrial facility in charge of electrical reliability. One of the most common failure points I deal with is electrical connections to large motors. I wrote a paper on this subject and the principles are the same. Although the means of failure are different, the oxidation is a major component in adding resistance to the connection.
The less interfaces, the better, so how does one achieve this?
Consider this; a cold weld is one that minimizes oxygen into the connection, a well done CRIMP will achieve this result. I recommend cleaning the copper conductor then immediately crimping on a connector of your choice. The purpose is to get the copper to 'cold flow' together, which removes all air voids between the metal. Then, if you wish, solder the connection, being careful not to flow onto the mating surface of the connector, for mechanical stability and to also form an airtight seal around the crimp. This type of connection at the lug has proven to be the best over many years of high current service. I replaced some equipment that had been exposed to H2S, very corrosive gas, for 20 years and the exposed copper was over 50% gone. I cut the crimped part of the lug apart and the copper looked brand new.
Now for the actual connection point at the speaker terminal. Pressure and oxygen free surface contact are key. I vote for a spade lug and screw type terminal. This is the easiest to keep clean and has the highest pressure potential between mating surfaces. Unfortunately many lower end speaker terminals are spring type. Regular cleaning is a good practice.
Deoxit is a good product to clean heavily oxidized parts, but MUST be followed by cleaning to remove the waste film. Then a protectant should be applied, Caig has a product 'Gold Shield' which works well. I am not promoting any particular product, just the process of CLEANING AND PROTECTION FROM OXIDATION.
To recap, PRESSURE, OXYGEN FREE CONNECTION are my two main points.
1. Banana is a good word to see at the start of a forum topic.
2. Since my main stereo speakers require banana connectors, I obviously use 'em. Gold connectors, good spring strength.
3. I have other speakers that I connect w/ spade lugs (gold, crimped and then soldered), and w/ bare wire.
4. If the connection is clean, good, and tight, then it's good. When I look at the surface area contacted between the above three types of connectors, I do NOT see a big difference. I think the bananas, with 4 spring leaves contacting, probably have the most contact in the connection.
5. My last amplifier's speaker output terminals held bananas OK. Never any problem, but when I replaced it, and found my new amplifer gripped them VERY firmly, I was happy. So, the associated equipment has something to do with the connectors, too.