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The Flat Earthers - Time for a Spring Clean
Back in the 1970s (or was it the early 80s? Getting older sure beats the alternative!), there was a great debate in the audio magazines about the "sound" of turntables. Some folks—let's call them the establishment—claimed that it made no difference whatsoever which turntable you used. Turntables were all the same, they said: "How on earth can a turntable add or detract from the sound of a hi-fi system? After all, it is not an amplifying device. It is just there to spin the record." This same group spent most of its time measuring, or trying to measure, distortion levels in amplifiers that were (and are) so minuscule that the attempt bordered on the futile, especially if you considered that you fed that beautiful, pure amplifier signal into a speaker system in which distortion could often be measured in tens of percents instead of thousandths. Still, those measurements were published and read by many audio enthusiasts, and held as gospel by some. Some folks still do!
Over in the other camp was another group. Let's call them the upstarts. They held almost the exact opposite view of the first group. They refused to make measurements, but instead just listened to their systems. Imagine that! They stated that the sound of the turntable influenced everything down the line, from the amplification stages through the wires to the loudspeakers. These guys were certain that the turntable affected the sound. Of course, this group subscribed to different magazines, ones that supported their view that the turntable was an important, if not the most important piece of the audio chain. One of the magazines was called The Flat Earth. It was British, of course, with lots of Linn Sondek tweaks and advertisements. The group that adhered to this philosophy became known as the Flat-Earthers. They were also doing things to their systems that most audiophiles at the time thought were sheer nonsense. It is some of those "other things" that we're going to talk about.
First, I don't think that anyone who owns a turntable today would dispute that the turntable is the make-or-break device in any analog chain. Some of the things that the Flat-Earthers concerned themselves with may be too esoteric for you. Then again, maybe they're not. I suggest that you try to stay open to the procedures I present here, and that you try some of them. They may result in an epiphany.
One of the things that the Flat-Earthers discussed was the "cleaning" of audio systems. When I read about this in The Flat Earth, I thought I'd try it. By cleaning, I don't mean dusting your equipment. You disconnect all of the cables and power cords to your components, then, using various cleaners, polishes, and contact-enhancing chemicals, you go to work. After the cleaning, you apply contact "stuff" to all of metal surfaces before putting things back together. The Flat Earth claimed that this made a big difference in the sound of a system. Before you say, "What a waste of time, I'm not going to bother to do all that," I suggest you try it. It made a big difference in my system back then, and it still does (even though everything today is more pure and more refined that what we had back in the dark ages, right?).
Improving your sound begins right at the wall, with your AC plugs, male and female, but stop right here. You're not going to insert anything into a live wall socket, are you? Please exercise caution, and if you're not comfortable with electricity, get someone else to do it. (You are CPR-trained, right?) A professional electrician probably knows what he's doing, so ask him some questions and learn how to do this work yourself.
Shut off the circuit breaker, then test the circuit using an appropriate instrument to make sure it's dead (and you're not!). If you're a real believer, you probably have already changed your wall sockets to audio-grade ones, probably at more than $50 apiece, with some costing more than $250! Some of the advantages of audio-grade pieces can be had with lower-cost alternatives—hospital-grade (Hubbell) sockets, available at any home supply mart for about $12. These duplex sockets really grab onto the male plug of your AC power cords compared to the fifty-cent outlets that came with your house. It is amazing how much extra effort is needed to insert and/or remove the male plugs from these outlets. When you pull the plug out, look at the scrape marks on the blades. The socket doesn't want to let go! This firm contact makes for a good, low-resistance electrical connection, and that means more information from the audio system. Every time I've changed an outlet in a system, mine or a friend's, it has made the system more revealing, more engaging, and well worth the modest effort.
After the outlet step, you will want to polish the blades of your power cord plugs before reassembling your system. Use a soft cloth and some good metal polish, and make those blades shine. This cleaning and polishing seems to produce more of a difference with expensive power cords than with the cheap ones the manufacturers throw in the box. This subject was revisited some time ago in the LP section of one of the major audio magazines, but only one brand of polish was mentioned, and there are many other brands that work just fine. The idea is to clean off any oxidized metal and make a pristine surface for that rock-solid electrical connection. This also makes a big sonic difference!
By now, you've figured out that we're going to clean every metal-to-metal connection in the system, but before you go nuts and clean everything, some of those RCA jacks and plugs have very thin precious-metal plating that you can destroy by using abrasive polishes. Don't use them! It's hard to explain why you are selling your two-year-old preamp with RCAs that don't have any plating on them. You really can't say "I cleaned those interconnects so much that I wore the plating off," so my recommendation is to only apply contact-enhancement chemicals to the RCA connections and gently wipe any excess liquid off with a soft, lint-free cloth.
Regarding contact-enhancement chemicals, the two that have made a difference for me are TPC (The Perfect Connection) by XLO, the cable people, and Craig's Pro Gold. The TPC is a wipe towelet that comes individually wrapped. One or two packets will do your whole system. The Craig is a liquid that comes in various sizes and delivery methods. My first purchase was a spray can, but now I use their pen applicator. The pen is more precise in its application to small parts, and the solution doesn't get all over the back of your equipment, as it can when you use the spray can. The pen also comes with replaceable tips, so if you wear one out doing tube sockets, you can use a fresh one for your RCAs. Use this stuff on all of the metal connection surfaces, and wipe dry before reconnecting.
I have a little battery-powered vacuum cleaner that is made for computers, and I use it to vacuum the dust from the circuit boards in my line stage and power amplifier. Dust decreases the insulating quality of whatever it is on, and is the enemy of electricity. Some line stages have cooling slots on the top and sides to let the heat out (and the dust in). This means you must take the metal top off, after removing a bunch of tiny machine screws, then put them back afterwards. You'll be ready for a glass of your favorite libation after this. Be gentle with the components and tubes (if you have them) inside of your gear. Because I never use the cloth grilles, I also very gently clean dust off the dome tweeters with the little vacuum cleaner.
When I went to the U. S. Army Signal School (a long time ago), tubes were still used in military gear, and we were told by our instructor; "Your greasy hands should never, and I repeat, NEVER touch those tubes. That greasy spot will burn onto the tube, and shorten its life." I have never seen that happen, and my experience with tubes goes back more than forty years, to the early Fender guitar amps. Today, some thoughtful equipment manufacturers supply white cotton gloves, which are just right for this part of the cleaning process. You can get the same gloves at a photographic supply shop, as they are used for handling film. They are not expensive, so get several pairs while you're at it. Be careful removing the dust from your precious tubes, because you can wipe off that ancient silk-screened script, thereby decreasing the value of your precious NOS tubes. Newer tubes seem to be much more resistant to this.
Check the system after reassembly. Is it on the level? I mean, is it literally level on your shelves? Are all the pieces of equipment sitting firmly? Are all of the feet distributing equal pressure down to the shelf? Can you slide a business card or a piece of paper under any of the feet? If so, then the gear is not balanced on its feet. You could try using three aftermarket feet, which might work better than factory set of four. Anything can work as a substitute foot. I like using small wooden blocks.
Turn everything on and listen to the system without any music playing. Do you hear any hum? Tube amplifiers, with their large transformers, are the worst culprits. Can you change the sound of a component by putting your hand on it? If so, try adding some weights. Brass and wood have worked best for me, but even a paperback book can lessen transformer hum. You can spend big bucks on these things, but the Mapleshade High Hats work well, and don't cost an arm and a leg. If you want to try an even cheaper solution, wash a glass jelly jar or two, fill them with sand, screw on the lids, and set them on the humming transformers. Move them around and adjust the amount of sand until the hum is minimized. If you decide that it's worth the money, you can always buy fancy weights later.
If you really want to get serious about vibration control, get a stethoscope, but buy the two-tube type, which will have higher resolution than a cheap single-tube model. Put on a compact disc that has a pink-noise band and hit repeat. Disconnect your speakers (open circuit), set the volume very low, and "listen" to the equipment with the stethoscope. Be careful with your ears—these instruments really amplify sound! The stethoscope has a high-gain, small-diameter side and a low-gain, larger side. Try both as you move the stethoscope around on the equipment. Learn the sound made by the pink noise throughout the system. You may be surprised at the different levels of response.
Listen to the pesky resonances you can easily hear with this device, then get control of them with everything at your disposal—machined brass weights, wooden blocks, weighted platforms, or whatever vibration-control tweak intrigues you. If you're looking for more detail, try devices like the FIM 305/3s, which have ball bearings in matching cups. Other popular brands of ball bearing support devices will also work. Each person will like something different, but I favor maple blocks for their musical warmth. My system is analytical enough for me. You can decide for yourself after some experimentation. Swap items with your buddies, and try each device for a week or more before making permanent changes or purchase decisions.
Use the stethoscope to check out your speakers, after reconnecting them. First, are they sitting solidly on their feet, or do they rock when you gently push on them? Spend some time making them sit properly on their feet or stands. Clean the binding posts and speaker cable connectors with contact-enhancement chemicals.
When using the stethoscope, you'll probably be shocked at the levels of pink noise being reproduced by the sides and backs of your speakers. Solid construction is one of the things that you pay for with those expensive brands. If the speaker panels vibrate too much, the result is colored sound. Don't bother with those stick-on damper things—just save up for better speakers.
If you are still using bare copper speaker wire, I have to ask why? You must have reasons. Perhaps your speaker manufacturer recommends this type of hook-up, but you have probably noticed that the wire has tarnished over time. This corrosion dulls the detail of your system. Redress the wire by clipping the ends and stripping back some insulation to make a new, shiny connection. That contact-enhancement chemical will slow down the oxidation of the copper, but a better approach is to crimp on a spade lug, or to solder on a spade or banana plug. Crimping is a very good method if you're not a good solder technician. Use the contact-enhancing chemical immediately after stripping and before you crimp on any connectors. The crimping tool makes airtight connections, but you must apply enough pressure. You should not be able to pull the lug off, even with pliers. My experience with twist-on connectors is that they are not good enough for a high-quality audio system, and are not worth the money. Spend your money on a good crimping tool. They are available for un-insulated or insulated connectors. The crimp-on lugs come in various sizes. Make sure that they fit your speakers' posts before crimping them on. You must make a solid mechanical connection using the crimping tool, even if you plan to solder the lug. Filling the open holes around the wire with solder will not result in the best-sounding connection. The un-insulated lugs will really bind the wire and stay on no matter what, but to make it professional looking, get some heat shrink tubing in two nice colors and color-code your terminations. Just slide the heat shrink over the lug and heat until it is snug.
After you reassemble your system, turn it on and give it a listen. Has your system perked up? Does the music sound clearer, brighter, and more alive than before? I sure hope so. You may even think it sounds too bright, especially if you haven't made any changes in a long time, but wait. It may take a day—or even a week—to sweeten up, and some systems will continue to improve after that. Some Flat-Earthers claim they do this every month, but three or four times a year is plenty for me. This article has probably told what you already know—that everything makes a difference! Those upstarts sure were onto something when they came up with these procedures. Energy flows where attention goes.