Not all non-soldered electrical connections are gold plated. Most metals other than gold tarnish relatively quickly, changing color over time. Copper is no exception, as I think most of us know. The tendency of copper, when exposed to air, water, and environmental pollutants, to turn red and then green, is well-known and even desireable in architectural applications of copper.
However, the copper oxide and copper sulfide formations which are responsible for such architectural color changes and patinas are not appreciated by audiophiles. Audiophiles like the metals in their systems to be bright and shiny. And audiophiles also like copper as a conductor. Exposed copper thus has to be kept bright and shiny. Audiophiles don't like tarnish because what looks bad tends to sound bad. Or so we believe.
"Pure copper" connections, such as used on some high-end speaker binding posts (e.g., Edison Price), bare wire speaker connections, power plugs, some electrical outlets, and all the power wiring in your house are potentially susceptible to this problem. And with exposed copper, if the connection is potentially susceptible to this problem, it will in fact happen in most instances, in my experience.
I have had many experiences with tarnished or corroded connectors becoming intermittent or failing altogether. This happens more frequently than I'd like with light bulb sockets in my house, particularly in lamps which have three-way sockets used with brighter incandescent bulbs. If tarnish or corrosion can make your lights blink or even fail to work, imagine what it does to your audio system's audio quality.
Much has been written on why tarnish/corrosion could matter from a sonic perspective. I don't think I have to go any further, however, than to note that tarnish and corrosion are metal oxides. The simple fact is that oxides of most metals (silver is an exception) are not conductive, or not very conductive and are at best classified as semiconductors. Tarnish thus sets up a high resistance junction in the circuit. Tarnish can act as a partial rectifier, introducing distortion into the circuit. Copper oxide rectifiers were indeed used intentionally as rectifiers in early semiconductor technology.
Thus, if you can see tarnish or corrosion on a non-soldered connection in your audio system, you should get rid of it. You also probably want to prevent that tarnish or corrosion from reappearing for as long as possible. This article will discuss what methods and products, in my experience, work well at accomplishing these goals, and which don't.
What Needs Cleaning
Basically, any non-gas-tight, non-soldered electrical connection could benefit from cleaning to remove dirt, atmospheric contaminants, tarnish, and corrosion. Gas-tight connections are those metal-to-metal connections which mechanically deform the conducting metal in such a way that no air or air-borne environmental contaminants can reach the metal surfaces which are actually in contact.
Unfortunately, many non-soldered connections within an audio system cannot be made gas tight. Sometimes the metals used are just too hard (i.e., they lack sufficient malleability) to be slightly deformed by the connective pressure which can be reasonably applied by that type of connection. RCA and XLR plug and jack connections are a classic example, even if they are of the "locking" type. And any speaker cable connection which does not visibly mar the connectors is not gas tight, not matter how seriously bulky or expensive it may be.
I find that copper speaker binding posts and copper power plug prongs are the absolute worst in terms of accumulating tarnish. If not protected (see later), "chrome" plated RCA jacks and plugs also can acquire a whitish tarnish.
The solid copper house wiring at your electrical box will look surprisingly good, in my experience. Rarely will such connections acquire heavy tarnish. It could be that higher current flow keeps these connections cleaner than others. Also, typical circuit breakers EASILY produce a gas-tight connection on solid copper wiring with just a screw driver to tighten the wire into the circuit breaker. You can tell this since you can see the spot on the wire where the connector has slightly nicked and deformed the solid copper house wiring. That nick will always be shiny clean. Would that all non-soldered audio connections could be so tightened!
House wiring at the outlet will also usually look pretty good. With decent outlets it is possible to get gas-tight connections which will not tarnish or corrode if you tighten them sufficiently with a screwdriver or use the back-wiring option, in which case a good outlet will nick the wire a bit and thus create a gas-tight connection.
Gold plated connections do not require tarnish removal, in my experience. Gold does not noticeably tarnish, at least if the gold plating is still in good shape. If the plating becomes scratched or removed through abrasion, however, the underlying metal may begin to tarnish, releasing contaminants onto the remaining gold's surface.
Why are not all connections in an audio system made with gold-plated metals? Expense, for one thing. In addition, there is a school of thought which reasons that gold is not as good a conductor as copper or silver and that platings of any kind, but creating more connections among dissimilar metals, somehow degrade the sound. This school of thought also notes that the gold-plating which looks the shiniest is often done by first plating the copper with nickel and then plating the nickel with gold, rather than directly plating copper with gold, adding more dissimilar boundary metal junctions. But, without taking a side on the sonics of gold plating, and regardless of the reason for lack of gold plating, it is a fact that not all connections in audio systems are gold plated.
What If You Can't See If It's Tarnished?
The type of cleaning you can do will vary depending on the metal involved and its situation.
I really can't determine the condition of power receptacle slots because I can't see inside them. The same usually goes for female IEC power cord slots. Ditto for the connections inside RCA and XLR jacks. I reason that if I can't see inside it, I probably shouldn't use any method to clean it which might leave an un-seeable cleaning residue inside. I can't be sure, with such connections, of rinsing out any non-evaporating cleaning substance. I also can't be sure that such residue would not have a deleterious sonic effect.
Thus, for such connections, I rely on a combination of two methods. First I use classic friction cleaning, that is, repeated making and breaking of the connection, combined with some rotation if the connection allows such movement. Such friction cleaning will disturb the oxide layer a bit and may remove or displace enough of it to allow a better connection, at least very temporarily. Second, I use some type of liquid cleaner, such as 99% isopropyl alcohol, which will totally evaporate in a short time.
I've found that the best way to apply such a liquid cleaner to small channels is with Dill's Premium Pipe Cleaners. Dip the pipe cleaner in the cleaning liquid and then ream out the channel with the pipe cleaner. Repeat at least once, using a fresh section of pipe cleaner each time. To clean the inside channels of the power and signal connections on my system usually requires about two packs of 32 pipe cleaners.
Getting Rid of Visible Tarnish and Corrosion
First, you need to (re)acquaint yourself with what truly clean and untarnished copper really looks like. Find an old piece of heavily tarnished copper and then use metal sandpaper or a dremel-like tool to mechanically abrade the oxides and sulfides until you are down to shiny metal over part of the surface. Now rinse the metal in distilled water, pat dry, and take a look, comparing the tarnished surface with the part you've just cleaned. What you will see on the clean part is very shiny, with only a hint of reddish-gold or yellow-gold color. It is far closer to the look of clean silver than to 24-carat gold, for example. THAT is what a truly clean and untarnished copper connection should look like.
What Doesn't Work
I have yet to find ANY liquid contact cleaner or treatment marketed to audiophiles which will remove such tarnish and corrosion in such a way as to come anywhere close to matching the look of the mechanically cleaned piece. Such products make big claims but, in my experience, come up woefully short on delivery. I'm specifically including Caig's DeOxit products here. No type of alcohol or now-scarce chloro/fluorohydrocarbon cleaners will do this job, either.
You will get some partial cleaning of tarnish with straight strong ammonia, but not anything close to the type of cleaning the mechanical method produced. And strong ammonia is nasty to work with in confined spaces because of the odor.
What Works
The methods and products which work usually involve at least some physical abrasion. The trick is to clean the connection using the least possible physical abrasion.
Metal sandpaper or a dremel-like tool obviously work well, but can be TOO good at what they do, reducing metal thickness or changing the shape of a contact via excess mechanical abrasion. They also tend to leave micro-scratches which may reduce the surface area of the connection if the metal is not malleable enough, or the connection is not tight enough to produce an air-tight connection by slightly deforming the metal under pressure.
Sometimes a nice clean rubber pencil eraser or "art gum" eraser will work wonders. I use this trick on somewhat-hard-to-reach surfaces such as the metal contacts inside lamp sockets. While it takes awhile to get rid of even moderate tarnish this way, it works better than straight ammonia.
Liquid and paste cleaners which I have found to work well include the following. When working with these, you may want to use vinyl gloves to protect your hands.
Sometimes cleaning is really impossible and you just have to start fresh with a new connection. With bare stranded speaker wire ends that have turned red or green, I just chop off a few inches every year or two and start fresh with a treated and protected connection since there is no way to effectively clean such thin, packed copper strands.
Cleaning a Shiny Connection
I clean the connections even on brand-new equipment. And even gold-plated connections can acquire dirt and atmospheric contaminants. To clean a shiny connection, I've had good sonic results with the following:
Protecting a Clean Connection
What Works Well
Rubbing alcohol--this is certainly the cheapest alternative. Anthony Padilla of MauiMods has recommended this approach and said he uses this on all his modification work. Rubbing alcohol leaves a bit of residue which may offer some protection from future tarnish or corrosion.
Kontak--see above. It is less messy to use than any spray, including my recommended Caig product below. If a bit of oily residue on the back panels of components or around connection points bothers you, Kontak is the one to use. Apply it with a Dill's Premium Pipe Cleaner and you will not get that sore of residue.
Caig Deoxit GXL/GX5 Gold spray--this is what I recommend. It was formerly known as ProGold and you will still find many references to it online by this name. I will use ProGold to refer to it below. I have used this in all my audio and video systems for over 15 years.
I only recommend this particular version of this product, which is quite diluted in strength (5% by volume) in this aerosol version. I have tried, but did not like the sonics or the gummy residue of the 100% product sold in vials for brush-on application. There is also a non-high-heat-resistance version of product which is sonically fine, but not AS fine as this version.
Caig's ProGold is a mild cleaner, but is primarily a contact enhancer. With ProGold, just spray, let the excess liquid drain off and evaporate a few seconds, then mate the connections, keeping your fingers off the connecting surfaces. ProGold is safe even for tube socket temperatures and is stated to be safe for use even inside electrical boxes and outlets, and I use it for such connections.
The decreased noise level, the expansion and rock-solid stability of the soundstage, and the taming of high frequency splash and frizzies cannot be had with any other cleaning/treating product, in my experience. As I believe HP once said, you don't know what a good connection sounds like until you use ProGold. Once you hear it, there is no going back.
If your connection is visibly dirty, I recommend using Kontak cleaner first, then ProGold. If you don't have Kontak, 99% isopropyl alcohol is okay for pre-cleaning and is cheap at only a few dollars a gallon at the hardware store. But if the equipment is new, just treat all the connections with ProGold right away and you will never see or hear a dirty jack or plug. I even treat all the unused jacks on a new piece of equipment and the cover them with Cardas caps. Such connections will look like new for many years.
I spray ProGold directly on the surfaces to be treated and do not wipe it off. I saturate the surfaces and let the cleaner drip down off the connector so as to remove contaminants that way. I do not wipe the connection with anything. Wiping any cloth surface on the connection will only leave deposits of lint or other contaminants on the surface or, worse, transfer contaminants from one treated connection to another if the same surface of the cloth happens to touch more than one connection. Also, the most important connections to treat are those which have the lowest contact pressure and these are usually not reachable with a cloth, e.g., RCA jack interiors and IEC power cord jack interiors.
I also use ProGold on connections I am about to solder. Classic soldering technique calls for making a robust physical connection before soldering. Treating that connection with ProGold before soldering enhances the sonics of the physical connection. If possible, solder should not be relied upon to actually MAKE the electrical connection. Soldering should be viewed as just adding a protection from physical contamination and physical stability to the connection. Solder, even sonically superior silver-content solder, is not an ideal metal for conduction.
Possible downsides of ProGold: It may cause mechanical fatigue of some plastic connector parts, but that is true of most cleaning products and this is far less problematic than even alcohol products in this respect, in my experience. In addition, use of the spray version I recommend WILL leave a bit of oily residue on the back panels of components or around connection points. This residue is visible and can be felt with your fingers. The residue is COMPLETELY removable by cleaning with ordinary Windex sprayed on a paper towel, but if you do that you undoubtedly will get Windex on your connections. If I am selling a piece, I use the Windex cleaning method; otherwise I just live with the residue.
What Doesn't Work Well
I used Tweek (aka Stabilant 22) for short while. It eventually turns brown and gooey. It added extra false top-end detail, basically by elevating the subjective response above the midrange. It thus skewed the frequency balance. I cast it into outer darkness long ago.
The prior Caig product called Cramolin also got gummy after awhile and besides that it made connections sound worse, not better, in my opinion, by creating unstable imaging and staging. It, too, got the boot after a single trial.
I do not recommend the paint-on liquid version of Deoxit Gold. It will get gummy like Stabilant 22/Tweek and Cramolin. Also, it just doesn't sound very good. This 100% paint on product produces a much brighter, thinner sound. You really do have to wipe that off to produce acceptably full-bodied sound and with some connections it is difficult to adequately wipe off.
What I Haven't Tried Yet
Walker and Mapleshade make contact-enhancing pastes which contain finely divided silver flakes. Many audiophiles have praised a combination of ProGold and these silver-containing pastes. I have Mapleshade's version of the silver paste, but have not yet tried it. I'm reluctant to try something which may be hard to remove. Finely divided bits of metal in a gooey paste could be a nightmare to get off if it proves not to be helpful. Many things that people like at first tend to be just different (usually brighter) rather than truly better. I will probably eventually try it on some very accessible surface like a speaker binding post.
Does Cleaning/Treating Really Make a Sonic Difference?
Of course, for those of you who doubt that cables make any difference, this cleaning and contact conditioning is all nonsense. Either you hear great sound or you have open circuit and no sound, right? For those folks, just use mechanical cleaning by making and breaking the connection a few times (throw in some rotation of the parts if the connection allows it) and you will have sound again for awhile.
Some folks argue that if you cannot hear a pair of cables inserted into the tape loop of an analog preamp by switching from source to tape, ProGold could not possibly make what was already sonically invisible more invisible. But the inserted cables may be invisible in the first place because you aren't using ProGold or otherwise following audiophile set up procedures. The signal path may already be so corrupted that adding another cable's wire and connections to the path via a tape loop makes an insignificant difference.
Here's an analogy. If you usually look at a scene through 20 panes of glass, each of which has a subtle film on it (you know what I mean about a film on glass which disappears with a good cleaning, right?) what you see may look "normal" to you and indistinguishable from what you see when you add the 21st pane of filmed glass. But suddenly clean all 20 panes and the scene may look different in a definitely better way. You might even be able to tell the difference if you add a single filmed glass to the path containing the 20 now-clean glass panes.
Here's the test I suggest: Clean all connections with whatever you believe to be the very best connection cleaner available to you. [If you don't believe cleaning makes any difference, then just skip this step.] Then play mono material, through both speakers or one at a time. Make sure both channels sound alike and produce a strongly centered mono image.
Now treat all the signal path connections of just one channel with ProGold. If you hear no difference between the channels, you will know that ProGold is not beneficial for your system. If you do hear a difference in favor of the treated channel, you will know what to do. If you hear a difference in favor of the untreated channel, just clean the treated channel again with your cleaner. ProGold comes off easily with isopropyl alcohol cleaners, for example.
In my experience, ProGold requires a bit of "curing" time to produce its sonic improvements. Some of the curing effect, might result from gradual vaporizing of some of the components of ProGold. Or, it might result from gradual migration of the substance through metal platings. The manufacturer makes claims for improved conductivity as a result of this migration.
My own experiments over the years long ago convinced me that amplifiers and other electronics need several days of constant-on powering to reach sonic stability. Four days or 100 hours seems to be enough. The same is true for connections newly treated with ProGold, but there the time required can easily be at least a week. One overall tendency of these warm-up/break in processes is a decrease in perceived brightness, a filling out of bass warmth, and greater perceived detail without brightness in the mids and highs. These effects have not been large with equipment I've owned. In other words, there is never a change from annoying to great. Nevertheless, there does seem to be a fairly consistent pattern of subtle to significant change.
Also, sometimes a newly powered up system or component can sound more dynamic in the macro sense. This effect can last for an hour or so. I think this is because there is actually a bit more brightness and/or distortion when the system or part of it is "cold."
I realize that there are possible flaws with my suggested test for the sonic efficacy of ProGold. I also don't think that treating your system with ProGold is as important as good speakers, room set up, or acoustic treatments, much less good recordings. The main things remain the main things. But I find ProGold provides an audible enhancement well worth its modest cost. It does not gild the lily; it cleans the glass through which you view the lily.
However, the copper oxide and copper sulfide formations which are responsible for such architectural color changes and patinas are not appreciated by audiophiles. Audiophiles like the metals in their systems to be bright and shiny. And audiophiles also like copper as a conductor. Exposed copper thus has to be kept bright and shiny. Audiophiles don't like tarnish because what looks bad tends to sound bad. Or so we believe.
"Pure copper" connections, such as used on some high-end speaker binding posts (e.g., Edison Price), bare wire speaker connections, power plugs, some electrical outlets, and all the power wiring in your house are potentially susceptible to this problem. And with exposed copper, if the connection is potentially susceptible to this problem, it will in fact happen in most instances, in my experience.
I have had many experiences with tarnished or corroded connectors becoming intermittent or failing altogether. This happens more frequently than I'd like with light bulb sockets in my house, particularly in lamps which have three-way sockets used with brighter incandescent bulbs. If tarnish or corrosion can make your lights blink or even fail to work, imagine what it does to your audio system's audio quality.
Much has been written on why tarnish/corrosion could matter from a sonic perspective. I don't think I have to go any further, however, than to note that tarnish and corrosion are metal oxides. The simple fact is that oxides of most metals (silver is an exception) are not conductive, or not very conductive and are at best classified as semiconductors. Tarnish thus sets up a high resistance junction in the circuit. Tarnish can act as a partial rectifier, introducing distortion into the circuit. Copper oxide rectifiers were indeed used intentionally as rectifiers in early semiconductor technology.
Thus, if you can see tarnish or corrosion on a non-soldered connection in your audio system, you should get rid of it. You also probably want to prevent that tarnish or corrosion from reappearing for as long as possible. This article will discuss what methods and products, in my experience, work well at accomplishing these goals, and which don't.
What Needs Cleaning
Basically, any non-gas-tight, non-soldered electrical connection could benefit from cleaning to remove dirt, atmospheric contaminants, tarnish, and corrosion. Gas-tight connections are those metal-to-metal connections which mechanically deform the conducting metal in such a way that no air or air-borne environmental contaminants can reach the metal surfaces which are actually in contact.
Unfortunately, many non-soldered connections within an audio system cannot be made gas tight. Sometimes the metals used are just too hard (i.e., they lack sufficient malleability) to be slightly deformed by the connective pressure which can be reasonably applied by that type of connection. RCA and XLR plug and jack connections are a classic example, even if they are of the "locking" type. And any speaker cable connection which does not visibly mar the connectors is not gas tight, not matter how seriously bulky or expensive it may be.
I find that copper speaker binding posts and copper power plug prongs are the absolute worst in terms of accumulating tarnish. If not protected (see later), "chrome" plated RCA jacks and plugs also can acquire a whitish tarnish.
The solid copper house wiring at your electrical box will look surprisingly good, in my experience. Rarely will such connections acquire heavy tarnish. It could be that higher current flow keeps these connections cleaner than others. Also, typical circuit breakers EASILY produce a gas-tight connection on solid copper wiring with just a screw driver to tighten the wire into the circuit breaker. You can tell this since you can see the spot on the wire where the connector has slightly nicked and deformed the solid copper house wiring. That nick will always be shiny clean. Would that all non-soldered audio connections could be so tightened!
House wiring at the outlet will also usually look pretty good. With decent outlets it is possible to get gas-tight connections which will not tarnish or corrode if you tighten them sufficiently with a screwdriver or use the back-wiring option, in which case a good outlet will nick the wire a bit and thus create a gas-tight connection.
Gold plated connections do not require tarnish removal, in my experience. Gold does not noticeably tarnish, at least if the gold plating is still in good shape. If the plating becomes scratched or removed through abrasion, however, the underlying metal may begin to tarnish, releasing contaminants onto the remaining gold's surface.
Why are not all connections in an audio system made with gold-plated metals? Expense, for one thing. In addition, there is a school of thought which reasons that gold is not as good a conductor as copper or silver and that platings of any kind, but creating more connections among dissimilar metals, somehow degrade the sound. This school of thought also notes that the gold-plating which looks the shiniest is often done by first plating the copper with nickel and then plating the nickel with gold, rather than directly plating copper with gold, adding more dissimilar boundary metal junctions. But, without taking a side on the sonics of gold plating, and regardless of the reason for lack of gold plating, it is a fact that not all connections in audio systems are gold plated.
What If You Can't See If It's Tarnished?
The type of cleaning you can do will vary depending on the metal involved and its situation.
I really can't determine the condition of power receptacle slots because I can't see inside them. The same usually goes for female IEC power cord slots. Ditto for the connections inside RCA and XLR jacks. I reason that if I can't see inside it, I probably shouldn't use any method to clean it which might leave an un-seeable cleaning residue inside. I can't be sure, with such connections, of rinsing out any non-evaporating cleaning substance. I also can't be sure that such residue would not have a deleterious sonic effect.
Thus, for such connections, I rely on a combination of two methods. First I use classic friction cleaning, that is, repeated making and breaking of the connection, combined with some rotation if the connection allows such movement. Such friction cleaning will disturb the oxide layer a bit and may remove or displace enough of it to allow a better connection, at least very temporarily. Second, I use some type of liquid cleaner, such as 99% isopropyl alcohol, which will totally evaporate in a short time.
I've found that the best way to apply such a liquid cleaner to small channels is with Dill's Premium Pipe Cleaners. Dip the pipe cleaner in the cleaning liquid and then ream out the channel with the pipe cleaner. Repeat at least once, using a fresh section of pipe cleaner each time. To clean the inside channels of the power and signal connections on my system usually requires about two packs of 32 pipe cleaners.
Getting Rid of Visible Tarnish and Corrosion
First, you need to (re)acquaint yourself with what truly clean and untarnished copper really looks like. Find an old piece of heavily tarnished copper and then use metal sandpaper or a dremel-like tool to mechanically abrade the oxides and sulfides until you are down to shiny metal over part of the surface. Now rinse the metal in distilled water, pat dry, and take a look, comparing the tarnished surface with the part you've just cleaned. What you will see on the clean part is very shiny, with only a hint of reddish-gold or yellow-gold color. It is far closer to the look of clean silver than to 24-carat gold, for example. THAT is what a truly clean and untarnished copper connection should look like.
What Doesn't Work
I have yet to find ANY liquid contact cleaner or treatment marketed to audiophiles which will remove such tarnish and corrosion in such a way as to come anywhere close to matching the look of the mechanically cleaned piece. Such products make big claims but, in my experience, come up woefully short on delivery. I'm specifically including Caig's DeOxit products here. No type of alcohol or now-scarce chloro/fluorohydrocarbon cleaners will do this job, either.
You will get some partial cleaning of tarnish with straight strong ammonia, but not anything close to the type of cleaning the mechanical method produced. And strong ammonia is nasty to work with in confined spaces because of the odor.
What Works
The methods and products which work usually involve at least some physical abrasion. The trick is to clean the connection using the least possible physical abrasion.
Metal sandpaper or a dremel-like tool obviously work well, but can be TOO good at what they do, reducing metal thickness or changing the shape of a contact via excess mechanical abrasion. They also tend to leave micro-scratches which may reduce the surface area of the connection if the metal is not malleable enough, or the connection is not tight enough to produce an air-tight connection by slightly deforming the metal under pressure.
Sometimes a nice clean rubber pencil eraser or "art gum" eraser will work wonders. I use this trick on somewhat-hard-to-reach surfaces such as the metal contacts inside lamp sockets. While it takes awhile to get rid of even moderate tarnish this way, it works better than straight ammonia.
Liquid and paste cleaners which I have found to work well include the following. When working with these, you may want to use vinyl gloves to protect your hands.
- Brasso or Wright's Brass Polish: Both of these liquids are ammonia-based, but have added finely suspended mechanical abrasives. The smell is a bit strong, but not overpowering, as is the case with full-strength ammonia. These will visually fully clean even heavily tarnished surfaces. You may have to use several iterations to get there, but patience has its rewards. Use the cleaner full strength, rub a lot with a rag, and remove with a soft dry or damp rag after each round of use of the fluid. With copper or brass tarnish, your wiping rag will get black; that's normal. These fluids also work to remove the tarnish or dullness on the typical "chrome" RCA female jacks on audio equipment.
- Noxon uses a different primarily active ingredient, oxalic acid, for its base, and seems at least equally effective at tarnish removal. It probably requires less iterations for complete cleaning. The base chemical has a different odor and Noxon is a bit more difficult to remove completely with water and alcohol rinsing.
- Flitz is a paste cleaner sometimes marketed to audiophiles. It works about as well as the liquid Brasso and Wright's Brass Polish. I find it a bit harder to use, however, because of its lack of flow. But that may be helpful in keeping the cleaner off surfaces you don't want to contaminate with it. Clean up after tarnish removal is the same as with the liquid cleaners and about equally difficult.
Sometimes cleaning is really impossible and you just have to start fresh with a new connection. With bare stranded speaker wire ends that have turned red or green, I just chop off a few inches every year or two and start fresh with a treated and protected connection since there is no way to effectively clean such thin, packed copper strands.
Cleaning a Shiny Connection
I clean the connections even on brand-new equipment. And even gold-plated connections can acquire dirt and atmospheric contaminants. To clean a shiny connection, I've had good sonic results with the following:
- Rubbing Alcohol--70% or 90% works well. This type of alcohol also leaves a bit of residue which may provide some protection from future tarnish. Sonically fairly neutral.
- Isopropyl Alcohol--I prefer the 99% stuff you can buy in a hardware store by the gallon. Sonically fairly neutral and it doesn't get in the way of the sonic and protective benefits of treatment products listed below.
- Kontak--I used this for many years. Sonically it is close to neutral, with just a tad of brightness. Most audiophile cleaning fluids are sonically MUCH worse. It leaves a protective residue, which may account for the touch of sonic brightness, but this residue seems to protect the connection for a long time. A ground connection to a copper cold water pipe I made after cleaning the copper with metal sandpaper and then treating it with Kontak stayed shiny clean for at least three years.
- Intraclean S-711 tape head cleaner, now replaced by S-721H--excellent cleaning for a non-ammonia based product. S-711 was a halogenated formula which was replaced by a more environmentally friendly product. Sonically, it is fairly neutral, about as close to neutral as Kontak, but without any protective residue. It doesn't get in the way of the sonic and protective benefits of the treatment products listed below.
Protecting a Clean Connection
What Works Well
Rubbing alcohol--this is certainly the cheapest alternative. Anthony Padilla of MauiMods has recommended this approach and said he uses this on all his modification work. Rubbing alcohol leaves a bit of residue which may offer some protection from future tarnish or corrosion.
Kontak--see above. It is less messy to use than any spray, including my recommended Caig product below. If a bit of oily residue on the back panels of components or around connection points bothers you, Kontak is the one to use. Apply it with a Dill's Premium Pipe Cleaner and you will not get that sore of residue.
Caig Deoxit GXL/GX5 Gold spray--this is what I recommend. It was formerly known as ProGold and you will still find many references to it online by this name. I will use ProGold to refer to it below. I have used this in all my audio and video systems for over 15 years.
I only recommend this particular version of this product, which is quite diluted in strength (5% by volume) in this aerosol version. I have tried, but did not like the sonics or the gummy residue of the 100% product sold in vials for brush-on application. There is also a non-high-heat-resistance version of product which is sonically fine, but not AS fine as this version.
Caig's ProGold is a mild cleaner, but is primarily a contact enhancer. With ProGold, just spray, let the excess liquid drain off and evaporate a few seconds, then mate the connections, keeping your fingers off the connecting surfaces. ProGold is safe even for tube socket temperatures and is stated to be safe for use even inside electrical boxes and outlets, and I use it for such connections.
The decreased noise level, the expansion and rock-solid stability of the soundstage, and the taming of high frequency splash and frizzies cannot be had with any other cleaning/treating product, in my experience. As I believe HP once said, you don't know what a good connection sounds like until you use ProGold. Once you hear it, there is no going back.
If your connection is visibly dirty, I recommend using Kontak cleaner first, then ProGold. If you don't have Kontak, 99% isopropyl alcohol is okay for pre-cleaning and is cheap at only a few dollars a gallon at the hardware store. But if the equipment is new, just treat all the connections with ProGold right away and you will never see or hear a dirty jack or plug. I even treat all the unused jacks on a new piece of equipment and the cover them with Cardas caps. Such connections will look like new for many years.
I spray ProGold directly on the surfaces to be treated and do not wipe it off. I saturate the surfaces and let the cleaner drip down off the connector so as to remove contaminants that way. I do not wipe the connection with anything. Wiping any cloth surface on the connection will only leave deposits of lint or other contaminants on the surface or, worse, transfer contaminants from one treated connection to another if the same surface of the cloth happens to touch more than one connection. Also, the most important connections to treat are those which have the lowest contact pressure and these are usually not reachable with a cloth, e.g., RCA jack interiors and IEC power cord jack interiors.
I also use ProGold on connections I am about to solder. Classic soldering technique calls for making a robust physical connection before soldering. Treating that connection with ProGold before soldering enhances the sonics of the physical connection. If possible, solder should not be relied upon to actually MAKE the electrical connection. Soldering should be viewed as just adding a protection from physical contamination and physical stability to the connection. Solder, even sonically superior silver-content solder, is not an ideal metal for conduction.
Possible downsides of ProGold: It may cause mechanical fatigue of some plastic connector parts, but that is true of most cleaning products and this is far less problematic than even alcohol products in this respect, in my experience. In addition, use of the spray version I recommend WILL leave a bit of oily residue on the back panels of components or around connection points. This residue is visible and can be felt with your fingers. The residue is COMPLETELY removable by cleaning with ordinary Windex sprayed on a paper towel, but if you do that you undoubtedly will get Windex on your connections. If I am selling a piece, I use the Windex cleaning method; otherwise I just live with the residue.
What Doesn't Work Well
I used Tweek (aka Stabilant 22) for short while. It eventually turns brown and gooey. It added extra false top-end detail, basically by elevating the subjective response above the midrange. It thus skewed the frequency balance. I cast it into outer darkness long ago.
The prior Caig product called Cramolin also got gummy after awhile and besides that it made connections sound worse, not better, in my opinion, by creating unstable imaging and staging. It, too, got the boot after a single trial.
I do not recommend the paint-on liquid version of Deoxit Gold. It will get gummy like Stabilant 22/Tweek and Cramolin. Also, it just doesn't sound very good. This 100% paint on product produces a much brighter, thinner sound. You really do have to wipe that off to produce acceptably full-bodied sound and with some connections it is difficult to adequately wipe off.
What I Haven't Tried Yet
Walker and Mapleshade make contact-enhancing pastes which contain finely divided silver flakes. Many audiophiles have praised a combination of ProGold and these silver-containing pastes. I have Mapleshade's version of the silver paste, but have not yet tried it. I'm reluctant to try something which may be hard to remove. Finely divided bits of metal in a gooey paste could be a nightmare to get off if it proves not to be helpful. Many things that people like at first tend to be just different (usually brighter) rather than truly better. I will probably eventually try it on some very accessible surface like a speaker binding post.
Does Cleaning/Treating Really Make a Sonic Difference?
Of course, for those of you who doubt that cables make any difference, this cleaning and contact conditioning is all nonsense. Either you hear great sound or you have open circuit and no sound, right? For those folks, just use mechanical cleaning by making and breaking the connection a few times (throw in some rotation of the parts if the connection allows it) and you will have sound again for awhile.
Some folks argue that if you cannot hear a pair of cables inserted into the tape loop of an analog preamp by switching from source to tape, ProGold could not possibly make what was already sonically invisible more invisible. But the inserted cables may be invisible in the first place because you aren't using ProGold or otherwise following audiophile set up procedures. The signal path may already be so corrupted that adding another cable's wire and connections to the path via a tape loop makes an insignificant difference.
Here's an analogy. If you usually look at a scene through 20 panes of glass, each of which has a subtle film on it (you know what I mean about a film on glass which disappears with a good cleaning, right?) what you see may look "normal" to you and indistinguishable from what you see when you add the 21st pane of filmed glass. But suddenly clean all 20 panes and the scene may look different in a definitely better way. You might even be able to tell the difference if you add a single filmed glass to the path containing the 20 now-clean glass panes.
Here's the test I suggest: Clean all connections with whatever you believe to be the very best connection cleaner available to you. [If you don't believe cleaning makes any difference, then just skip this step.] Then play mono material, through both speakers or one at a time. Make sure both channels sound alike and produce a strongly centered mono image.
Now treat all the signal path connections of just one channel with ProGold. If you hear no difference between the channels, you will know that ProGold is not beneficial for your system. If you do hear a difference in favor of the treated channel, you will know what to do. If you hear a difference in favor of the untreated channel, just clean the treated channel again with your cleaner. ProGold comes off easily with isopropyl alcohol cleaners, for example.
In my experience, ProGold requires a bit of "curing" time to produce its sonic improvements. Some of the curing effect, might result from gradual vaporizing of some of the components of ProGold. Or, it might result from gradual migration of the substance through metal platings. The manufacturer makes claims for improved conductivity as a result of this migration.
My own experiments over the years long ago convinced me that amplifiers and other electronics need several days of constant-on powering to reach sonic stability. Four days or 100 hours seems to be enough. The same is true for connections newly treated with ProGold, but there the time required can easily be at least a week. One overall tendency of these warm-up/break in processes is a decrease in perceived brightness, a filling out of bass warmth, and greater perceived detail without brightness in the mids and highs. These effects have not been large with equipment I've owned. In other words, there is never a change from annoying to great. Nevertheless, there does seem to be a fairly consistent pattern of subtle to significant change.
Also, sometimes a newly powered up system or component can sound more dynamic in the macro sense. This effect can last for an hour or so. I think this is because there is actually a bit more brightness and/or distortion when the system or part of it is "cold."
I realize that there are possible flaws with my suggested test for the sonic efficacy of ProGold. I also don't think that treating your system with ProGold is as important as good speakers, room set up, or acoustic treatments, much less good recordings. The main things remain the main things. But I find ProGold provides an audible enhancement well worth its modest cost. It does not gild the lily; it cleans the glass through which you view the lily.