FAQs - Vintage Audio Equipment Repair and Collecting
Q. What characteristics would classify a given piece of audio equipment as “Vintage”, Antique” or “Classic”?
A. “Vintage” would generally mean any piece of gear that is older than about 25-30 years. “Antique” usually refers to items made before the 1960’s, although some would draw the line earlier yet, such as anything before WWII.
“Classic” implies a quality of specialness applied to either of the above time periods. It might be a rare item that is collectible simply for that reason, but more commonly means a product that performs much better than average either for its day or even by contemporary standards. In audio, names such as McIntosh, Marantz, Fisher, Scott, 1960’s & 70’s Sansui, Yamaha or Pioneer tend to come up. There are of course numerous others.
Q. Can any of this equipment compete successfully with modern equipment as to audio quality?
A. Yes, some of them can, depending on what the component is. Power amplifiers, FM radio tuners and preamplifiers tend to hold up the best, record players somewhere in the middle, speakers and tape decks the worst. Many amplifiers from the 1960’s to 1980’s can still equal all but the very best of modern amplifiers, assuming they are in good working condition.
Q. Wouldn’t their age tend to preclude them being in “good working condition”?
A. Yes, thus the need to perform the necessary service to bring them up to par. It is extremely rare to find any audio component over 30 years old that will not require some service work, either to make it functional if it is broken, or simply to improve the audio quality or reliability.
Q. What kind of work is typically needed?
A. The single most common issues fall into two areas. One, the controls, switches, and relay contacts must be cleaned and de-oxidized. While atmospheric dust and smoke has an effect, the biggest offender is simply oxygen which is naturally in the air, and will eventually permeate even “sealed” controls. The metal contacts in the controls and switches become oxidized, and metal oxides are almost always insulators, blocking the flow of electrical current. Crackles, noises, and intermittent or total signal loss result.
Two, there are passive components such as resistors and capacitors that can fail with age. Of the two, capacitors are the more common problem, and in particular a specific type of capacitor known as an “electrolytic”. Electrolytics have a finite lifespan, even if the component has been in storage and has not been actively used. This lifespan varies tremendously—some ‘lytics are weakening after only a few thousand hours of use, while others are still operating after 40 or 50 years. On average, though, any audio component over 25 to 30 years should have some of the capacitors (or “caps” in tech slang) at least tested, and then all similar parts replaced if a good percentage test poorly.
Q. If these electrolytics have a short lifespan compared to other types of capacitor, why are they used? Is it just planned obsolescence?
A. Not in most cases. Electrolytics have a very high capacitance value per unit of physical size. If the circuit design calls for a high value of capacitance, an equivalent non-electrolytic cap might be far too large to fit on the circuit board or in other available space. The difference generally isn’t trivial—a 1000 microfarad electrolytic could be the size of a few sugar cubes, a 1000 microfarad polyester film capacitor could be the size of your fist.
Q. What happens when these capacitors fail?
A. It depends on what part of the circuit they are in. If they are in the power supply, most times loud hum will result or else the power supply will short out and the component will stop working. If they are in the audio signal path, the audio often becomes erratic, distorted or disappears altogether. In some cases capacitor failure will lead to damage of tubes, transistors or other components. The latter situation is an example where the failure of a $1.00 part could cause hundreds of dollars in cascade damages.
Q. What about tubes? Those wear out too, right?
A. Yes, although tubes made back in the 50’s and 60’s were usually very well made and other than power (output) tubes could work well for decades. These can be replaced as needed while fixing up an older component.
Q. I’ve heard that new tubes are very poor, and because of that many vintage audio hobbyists look for “NOS” or “New Old Stock” tubes for their repair work.
A. This was a major problem with repairing vacuum tube gear back in the 80’s and 90’s, but now there are good sources for quality new tubes from a variety of vendors. Also, NOS tubes can usually be obtained from other companies if a new tube cannot be obtained.
Q. Is the new interest in vintage tube gear being driven by the fact that this equipment, when operating properly, sounds better than the newer transistorized gear?
A. This question has shifted into something of an almost religious aspect, and this FAQ is not going to go there. However, whether evaluated from an empirical, measurement basis or by simply listening, either method can work extremely well. If you prefer the sound of tubes over transistors, or vice versa, go for it. It’s your ears and brain-- you hear what you hear.
Q. Is the tube equipment more reliable than solid state gear? I mean, if it wasn’t, how could this stuff have lasted for 50 years or more?
A. No, not if the design is done properly and the product is constructed with longevity in mind. Transistors, if not overheated or otherwise stressed beyond their limits, could last 40 or 50 years easily. Note that poor designs that stress their tubes will fail early also. The totality of the design is far more important than the specific components.
Q. Which is harder to work on from a repair standpoint, tubes or transistors?
A. Tube equipment is generally easier to service, but on the other hand uses very high voltages in the chassis compared to most solid state designs. If you are servicing equipment yourself, you must be extremely careful or you can be injured or killed by these high voltages. Beyond that, the individual simplicity or complexity of the design will usually dictate how hard the service procedures will be.
It’s worth noting that it is far easier to make complicated designs with transistors and integrated circuits than it is with tubes, and this can lead to tricky diagnostic work at times. If the complex circuit performs a useful function, then the trade-off is usually worthwhile. If the added function is of little or no practical importance—i.e. the engineers are just kind of showing off—then such products are ones best avoided.
Q. If I wanted to do most or all of the repair and refurbishing work myself, what are the basic tools and knowledge set I would need?
A. If you want to become a serious participant in this field, you will need a good basic understanding of electronic theory, the ability to recognize all common circuit components inside a product, a good sense of how they perform in the circuit, and the ability to use test equipment and understand the results it provides.
Essential test equipment would be a DVM (digital voltmeter), a variable AC transformer (often called a “Variac”), a sine wave generator, an oscilloscope and a load box, plus of course proper soldering and desoldering equipment and a workbench with basic hand tools. The next purchase should be a THD analyzer or an interface box and software to allow a computer to perform that function. If you want to work on tuners, an FM (or AM/FM) signal generator with stereo capability is essential. Tape decks will require test tapes to make objective measurements and perform head alignment. Record player work will require test records, tonearm alignment jigs and a microscope.
Q. How much will that cost? Can I buy good used gear to save some money?
A. If you buy new, expect to pay a few thousand dollars minimum. If you shop carefully on the used market, you can probably cut that by half or even a third. Visit online audio / DIY forums and often you will find members who are buying/selling/swapping test gear, or directing other forum members as to where to find good deals. This DIY audio community is usually very supportive of other audio hobbyists and is an excellent resource for same.
Q. Can older gear be improved by fitting it with more modern components, or altering the design to more contemporary ones?
A. Yes, but great care must be exercised in doing so. You should posess a high level of understanding of the original design before you attempt to alter it. It is presumptuous to assume that the engineers responsible were not aware of any trade-offs that they might have made for a production product, and had good reasons for them. Sometimes it’s about costs, but not always.
In short, don’t change things unless you are sure a benefit will result without a tradeoff, perhaps a serious one.
Q. What percentage of vintage gear is genuinely valuable?
A. Depends on, as always, the qualifier “Valuable to whom?” To a hobbyist or collector, it’s a model he or she would very much like to own, for whatever personal reasons. To an average person who just wants a decent sounding sound system on a budget, it has little value at all, since after the repair and refurbishing work the price isn’t really any lower than a decent new component or compact system.
There are few—exceedingly few—audio components that become monetarily valuable over time. Vintage audio isn’t a good hobby to get into if your primary concern is making yourself a nest egg with it. It can be a very enjoyable and emotionally rewarding hobby if your goal is to obtain good music from a machine that was well made by people who cared about what they were building and that deserves to be enjoyed for as long as reasonably possible. It keeps said good stuff from getting chucked into landfills. It has an undeniable retro aesthetic to it.
I suggest you enjoy it for what it is, and don’t concentrate on it as an investment other than in whatever pleasure it brings you.
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