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11#

19.0 Miscellaneous:
19.1 What do I need to know about warranties?
19.2 What is blind testing? Non-blind? Double-blind?
19.3 Where can I get a service manual for brand XXX?
19.4 Where can I get good repairs on brand XXX?
19.5 How can I take 115V gear over to a 230V country or vice versa?
19.6 Are there really good deals in country XXX?
19.7 How do I find out how much an XXX is worth?
19.8 Do people really hear those differences?
19.9 Why do people disagree on what is the best sound?
19.10 How do I contact the manufacturer of XXXXX? How do I get repair service on XXXXX? How do I get replacement parts?

19.1 What do I need to know about warranties?
Warranties have a few basic components. The first is the term of the warranty. The second is what is covered. The third is who supports the warranty. The fourth is what restrictions.

Term is fairly self evident. What is covered is more detailed. In audio electronics, typically everything is covered with a "parts and labor"" warranty. Often mechanical components such as tape heads are covered by different terms, such as shorter terms on labor and longer terms on parts. Likewise, speaker warranties vary widely, from unconditional with no term limit to a basic 30 days parts and labor.

Some warranties come from the manufacturer. Others come from the dealer. Still other warranty support is available with certain premium charge cards.

A common restriction on some warranties is that the equipment is not covered unless it is sold by an authorized dealer. A few dealers have lied about being authorized dealers. Equipment sold by an unauthorized dealer is almost always sold completely legally. This unauthorized dealer may, in fact, be fully authorized to sell, but not authorized to sell manufacturer's warranties. In buying gear this way, dealers can get it cheaper, and provide the service themselves. This kind of gear, with a full warranty from the dealer is referred to as gray market equipment. Manufacturers discourage buying from these gray market dealers, but the risks are fairly low. If the dealer is local and well established, the risks are minimal.

If you buy equipment mail-order, a dealer warranty may be a pain in the neck, especially if you have to ship the gear to the dealer more than once to get it fixed correctly. Then again, some factory service requires shipping gear far away at your expense, too.

Frequently, home audio equipment is sold with a warranty restriction that if the gear is used commercially or in any profit-making enterprise, then the warranty is void. This is to protect the manufacturer from having to frequently repair equipment meant for light service. Professional audio equipment often comes with very liberal warranty terms, such as lifetime parts and labor. Professional gear takes heavy use and severe wear from constant transportation. It is expected to be able to take this abuse.

All gear, electronic and mechanical, is known to have three principal failure modes: abuse, infant failure, and end-of-life failure. In addition, a few of the failures occur at random.

Infant failure occurs in the first fifty hours of use, and is the principal responsibility of warranties. Infant failure is frequently caused by defective parts or a design defect.

Abuse failure is that caused by a person who pulls a cable too hard, bangs the equipment on the table, pushes the controls too firmly or too fast, or does anything else which the manufacturer did not expect. These are the gray areas of warranties. They do not represent a manufacturing defect in the manufacturer's eyes, but they do leave you with a broken device. To get the best chance of coverage against this kind of failure, select a brand or a dealer with a very liberal warranty policy.

End-of-life failures are rarely covered by warranty. Tape heads have a finite, calculable life, as do rubber rollers, speakers, cables, batteries, bearings, and motors. The life of some of these components can be extended by intelligent care. For example, the life of common rechargeable batteries can be extended by good recharging practice. Likewise, some cleaners can dry out rubber, and will lead to premature failure. Don't expect warranty support for any of these problems, and if you get it, feel lucky.


19.2 What is blind testing? Non-blind? Double-blind?
If you want to compare pieces of equipment, recordings, or people, you could run an experiment. You could select an experimenter to initiate various trials, select some subjects to listen to the sounds, and then ask the subjects questions about what they hear. However, if you want meaningful results, it is necessary to set up the experiment correctly, and ask the right questions.

One of the major problems with any experiment is that the subjects may become aware of the experimenter's hypothesis and allow this awareness to influence their behavior. One technique for preventing such bias is to keep the person who conducts the experiment unaware of the hypothesis of the research. Unfortunately, experimenters invariably form SOME hypothesis of what's going on, and these hypotheses affect how they deal with subjects.

A more reasonable solution involves allowing the experimenters to know the true hypothesis but somehow keeping them ignorant of the specific experimental condition of each subject. This is known as a Partial Blind Experimenter technique. An example of this is that the person running an experiment knows that the main experimenter wants to determine which connecting cables are best at signal carrying, but would not know which cables are being used at any given time during the experiment.

It is also important for subjects not to become aware of the experimenter's specific hypothesis. Subjects often become highly responsive to any cues, intended or unintended, in the research situation that suggest what they are supposed to do to appear normal or "to make the study come out right." This problem can be present in judgment experiments, particularly those in which each subject is exposed to more than one variation of the stimulus. Such a procedure, by its very nature, increases the probability that the subject will begin to guess which aspects of the experiment are being systematically varied by the experimenter.

Many studies avoid this problem with what is called a Blind Subject technique. Using this approach, subjects are not told specifically what the hypotheses are. Additionally, subjects are not told what specific experimental conditions they are in. For example, a subject might be told that he/she is supposed to determine which stereo system sounds better, when in fact the experimenter wishes to examine which color or appearance of the same components looks better to subjects.

When both a Partial Blind Experimenter technique and a Blind Subject technique are used at the same time, this is called a Double Blind experiment. Double Blind experiments have higher probability of producing statistically valid results than Partial Blind Experimenter alone, Blind Subject alone, or other techniques. Double Blind experiments are highly recommended.


19.3 Where can I get a service manual for brand XXX?
The most reliable source of supply is the manufacturer's sales office in your country. Here is a list of company contacts that may be helpful in the US. (Please send additions & corrections etc. to neidorff@uicc.com)


    AOC            800-775-1262
    Cannon            516-933-6300
    Casio            201-361-5400
    Daewoo            800-782-4922
    Emerson Radio        800-388-8333
    Sanyo/Fisher        213-605-6756
    General Electric    800-447-1700
    Goldstar        800-222-6457
    Hitachi            800-526-6241
    JVC            800-252-5722
    Kenwood            213-639-9000
    Philips/Mag/Sylvania    615-475-8869
    Mitsubishi/Akai        714-220-1464
    NAD            617-762-0202
    NEC            201-882-9008
    Nutone            800-543-8687
    Onkyo            201-825-7950
    Panasonic/Quasar    215-741-0676
    RCA            317-231-4151
    Samsung            800-542-1302
    Sanyo            800-421-5013
    Sharp            800-526-0264
    Sony            800-282-2848
    Soundesign        800-888-4491
    Teac            213-726-0303
    Teknica            800-962-1271
    Toshiba            201-628-8000
    Zenith            312-745-5152

Alternately, contact one of the repair parts dealers listed in section 10.15 above. MCM and Parts Express offer free catalogs which can be very helpful for locating parts.


19.4 Where can I get good repairs on brand XXX?


19.5 How can I take 115V gear over to a 230V country or vice versa?
Some equipment is available with an international power supply, which can be rewired by any serviceman to either power line voltage. If you expect to be moving abroad, look for this kind of equipment. Often, the same model is available both as US only and as International. Some equipment will be rewirable and won't say it. Adcom amps are known to be rewirable.

If you know that your gear is limited to one power line voltage, you can order a new power transformer for that receiver, CD player, amplifier, or tuner which will be wound differently. Contact the manufacturer's local service center. This can be very expensive. A new transformer for a 40 watt receiver would wholesale for under $25 but cost $75 from a service center.

Another alternative is to buy a power transformer that will convert 115V to 230V and vice versa. This is only practical for smaller gear. Larger power amps require prohibitively massive and expensive transformers. Also, the addition of a transformer may hurt the sound quality.

Here are some common transformer models and 1992 list prices. Power ratings are total line current multiplied by line voltage (2A at 115V is 230 watts). Larger transformers cost more. Some of the costlier transformers are constructed with plugs and jacks for immediate use. Those marked * have wire leads and need safe connections to be used.

Before spending money, check into other things about audio in the new country. Broadcast frequencies are slightly different in some countries than in others, so a receiver or tuner bought in one country may not be able to receive some or all of the stations in another country. The US separates the AM broadcast band frequencies by 10kHz while the UK uses 9kHz. Similarly, the US separates FM stations by 200kHz, where the UK has stations on a 50kHz spacing pattern. It MAY be very simple to modify a receiver from US to UK spacings, but may not. Last, but not least, some equipment will NOT work well on 50Hz power.

        Step Down (230V in, 115V Out)
                MagneTek/Triad  N1X*    50 Watts        $11.83
                Stancor         P-8620* 50 Watts        $14.16
                MagneTek/Triad  N3M     85 Watts        $29.95
                Stancor         P-8630  85 Watts        $43.65
                MagneTek/Triad  N6U*    200 Watts       $25.72
                Stancor         P-8632  200 Watts       $51.80
                MagneTek/Triad  N5M     250 Watts       $42.60

        Step Up (115V In, 230V Out)
                Stancor         P-8637  85 Watts        $43.10
                MagneTek/Triad  N150MG  150 Watts       $49.46
                MagneTek/Triad  N250MG  250 Watts       $54.69
                Stancor         P-8639  300 Watts       $55.51

The Stancor and MagneTek Triad lines are carried by large electronic distributors.


19.6 Are there really good deals in country XXX?


19.7 How do I find out how much an XXX is worth?
There is a "Blue Book" for used audio equipment called "Orion Blue Book-Audio". This guide lists both a wholesale and a retail value for most audio gear.

                
        Orion Research Corporation
        1315 Main Avenue Suite 230
        Durango CO  81301 USA
        303-247-8855

Last I knew a guide costs $169. Each Nov, a new book is printed. After June, the old book is discounted. If you need a single quote from the Orion Blue Book, send a polite request to:

                al@qiclab.scn.rain.com

and you may get a quote back by e-mail.


19.8 Do people really hear those differences?
Who knows? They sure think that they do.


19.9 Why do people disagree on what is the best sound?
There are at least three different measures of what is "Perfect Sound". All three have advocates, and all three are right, in their own way. In general, whether they admit it or not, most listeners fit into one of these three preference groups:

1. It must sound like live music. These people know what voices sound like in person, they know what instruments sound like without any amplification, and they have heard orchestras perform unaided by sound systems. They want to accurately reproduce that sound.

2. It must sound like the recording engineer wanted it to sound. The recording engineer listened with extremely good equipment to the sound coming out of the microphones, and mixed them together for what he, at that time, felt was artistically correct. It may not have been the same as live, but it was exactly what he wanted. In the extreme, people like John Fogerty used to audition his final recording mix in his truck to see how it would sound through a common, lousy stereo.

3. It must give me the most pleasure. No matter how good or bad live sounds, no matter what the recording engineer intended, if buy some equipment will give me more listening pleasure then it must be the best.


With these three perspectives, it is clear that no one system will satisfy everyone. Add to that confusion the variable that everyone likes a different kind of sound, has heard live music under different conditions, and has a different idea of what the engineer intended. There is an enormous range of possibilities.

Another set of reasons is that people look for different things to be right. Some want strong bass; others want male voices to sound like male voices; others want violins to sound like violins. Systems rarely do everything equally well. Speakers (in particular) are compromises. Look for the speaker where the designer had your priority first. You are perfectly right to select speakers based on YOUR personal taste.

Confounding the situation further, we all say the greatest things about the stuff we already bought. To do otherwise would be to admit that we are either stupid or deaf.

Still another reason is that most people haven't heard enough variations. Until you hear a system that can truly reconstruct the three-dimensional accuracy of a stereo image accurately, you may never realize that it is possible. Some excellent recordings contain enough information that with a good enough system, you can hear up-down, in-out, and left-right distinctions very clearly. However, we will never experience this until we are fortunate enough to hear such a fine recording on a very good system.

Finally, some of us really can't hear much difference. We aren't deaf, but we don't have a well trained ear, don't know exactly what to listen for, and may even have slight hearing deficiencies, such as bad sensitivity to high frequencies which comes with older age, or hearing damage from listening to loud sounds (machinery, rock concerts, etc).


19.10 How do I contact the manufacturer of XXXXX? How do I get repair service on XXXXX? How do I get replacement parts?
Some magazines publish lists of contact phone numbers for the manufacturers of equipment. In the US, Consumer Reports has a small listing in each issue and a more comprehensive listing in their March issue. Also, Audio Magazine has an exhaustive listing in their October "Equipment Directory". In Europe, look in "What HiFi?".

You can find many addresses by reading ads in hifi magazines. You can also find out by asking at your friendly local hifi shop, especially if you've built up a relationship with them.

There is a book called the "Electronics Industry Telephone Directory". It comes out yearly and is available in some libraries. Many reps from parts distributors pass them out for free. If you want a copy and are willing to pay for it, call Harris Publishing, 800-888-5900 or 216-425-9000.

The directory of the Electronic Industries Association is similarly useful. You can reach the EIA at 202-457-4900.

A good source for parts and service is often the manufacturer's repair center. The best way to locate one near you is to look at the literature which came with your equipment when it was new. Failing that, see the ideas mentioned above in 19.10.


Back to main index - Continue to 20.0 Net Protocol
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12#

18.0 Retail:
18.1 Should I use an up-scale retail store?
18.2 Should I use a discount store?
18.3 Is it right to negotiate price?
18.4 How can I negotiate price effectively?
18.5 It sounded great in the store. Is it great?
18.6 Do sales people try to trick the customer?
18.7 How can sales people trick the customer?
18.8 What should I ask the sales person?
18.9 How do I impress the sales person?
18.10 How do I get the best service from a sales person?

18.1 Should I use an up-scale retail store?
This is probably the best place to listen to gear in a controlled environment, next to your home. This is the best place to find expensive, high quality gear. This is the place which is most likely to have a good policy on home trials and a liberal return/upgrade policy. This is also likely to be the most expensive place to shop. One exception to this is that these stores have the ability to sell demos, returns, and discontinued gear at very advantageous prices.

Some up-scale dealers will negotiate price on large systems or expensive purchases. It never hurts to ask.

There are definitely better and worse local hi-fi stores. If you find a really good one, it is probably worth the extra money to buy from them, rather than from discounters. A really good store will not push you to buy what they want to sell. A really good store will allow you to take your time with your decision. A really good store will not distort the truth in describing equipment. A really good store will help you get the most out of your purchase by showing you how to set it up. They will tell you what placement works best for the speakers. (Don't believe them if they tell you to put them anywhere.) A really good store also selects their lines carefully. They don't want dissatisfied customers or warranty returns any more than you do. A really good store will also have technical equipment and/or skilled technical people that can perform tricky adjustments correctly, such as cartridge and tonearm alignment.

Due to the nature of the customer, a hi-fi store in a shopping mall is likely to use high-pressure sales techniques. They know that the majority of their customers are distracted easily by 299 other stores. Most of their sales go to customers that come in for 3 minutes, select something, and leave. There are exceptions to this, of course, but if there was a good generalization, it would be to look elsewhere. There are stores in large buildings, small buildings, private homes, shopping plazas, and every other conceivable venue. Search from among these to find one that meets your needs and fits your style.


18.2 Should I use a discount store?
If you need to listen carefully before making up your mind, discount stores can be very frustrating. If you know exactly what you want, then this can be a great place to save money. Don't expect knowledgeable sales help or after-sale support. Be sure to ask about the warranty (see 19.1 below on warranties).


18.3 Is it right to negotiate price?
Most people feel that it is fair to negotiate. Some feel that it is fair to lie in negotiating, as the sales people frequently lie to you also. Others think that lying to get a lower price is an immoral practice. It may even be illegal, an act of fraud.

Some people feel that if you negotiate over price, you encourage stores to mark prices artificially high, so that the stores have room to negotiate. Others feel that in negotiating, you are asking the store to accept a lower profit, or asking the sales person to take a lower commission and are directly hurting them.


18.4 How can I negotiate price effectively?
A great source of information on this topic is available from books on buying a new or used car. However, some very helpful general tips include:

Know the competition and the dealer. Know the gear. Know the prices available elsewhere. Believe in your research, not their words. Stand your ground. Be nice to the people but hard on the deal. Be prepared to walk away if they won't agree. Expect their lines and prepare responses in advance.
For example, expect the dealer to claim that the Nakamichi deck is the best cassette deck on the market. Be ready with a reply such as at that price, you can buy a DAT machine which has better frequency response, lower signal to noise ratio, etc.
18.5 It sounded great in the store. Is it great?
Never let anyone else pick stereo for you. Especially not speakers. They all sound different, and you don't need a golden ear to hear the differences. Listen for yourself and ignore what the sales people say.

If you are still unsure, ask the sales people to let you take the gear home for a home trial in exchange for a large deposit. Home auditioning takes 99% of the risk out of store auditions.


18.6 Do sales people try to trick the customer?
Some do and some don't. Some will treat unpleasant customers badly and treat friendly people well. Most sales people aren't wealthy. They sell stereo to make a living. If they can sell you a more expensive piece of equipment or a piece of equipment with a higher profit, they will make more money. Usually, this figures into everything they say. Some sales people claim to be altruistic.

Some sales people really are open and honest. They may starve with this approach, or they may have a nice enough personality, a good enough product line, a good enough store behind them, or enough technical background to overcome this "limitation".


18.7 How can sales people trick the customer?
Often, a customer will trick him or herself without help. We are often swayed by appearance, sales literature, position of the equipment in the show room, and our own desire to buy what others will like.

Some times, the sales person will actively try to push a particular piece of equipment by demonstrating it against another piece of equipment which is inferior or defective.

Some sales people will demonstrate a set of speakers while simultaneously driving a subwoofer, even though they are not telling you this. With the subwoofer, it probably will sound better.

Some sales people will demonstrate one set of speakers louder than others. Louder almost always sounds better.

Most stereo buyers go into the store, spend a few minutes selecting what they want, lay down big bucks, and leave. They don't need to be tricked. They don't listen carefully. They trust the sales person's choice as best in their price range. For non-technical reasons, these people are the most likely to be satisfied with their purchase.


18.8 What should I ask the sales person?
What do you want to know? Seriously, the best questions are those which the sales person can answer without distorting the truth. Don't ask a sales person to compare their brand to a brand they don't sell. Don't ask "how good is the ...". Ask questions of fact.

Here are some questions you may want to ask:

If I don't like it can I return it for a full refund? Can I try this out at my home in exchange for a deposit? What does the warranty cover? For how long? What do I need to know to set this up for best sound? Do I get a manufacturer's warranty with this? Where do I take this to get it repaired under warranty? Where do I take this to get it repaired out of warranty?
18.9 How do I impress the sales person?
Why would you want to? You have money and he doesn't.


18.10 How do I get the best service from a sales person?
Be honest with the sales person. Set some reasonable request and ask them to meet it. For example, say that you will buy this if you can try it at home first and listen to it side-by-side with a piece from another store. Alternately, say that you saw the same thing at store Z for $xx less, but you will buy it from the guy if he will match the price.


Back to main index - Continue to 19.0 Miscellaneous
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13#

看不明,英文都还给老师了。
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14#

看不动
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15#

L版,实在大长編大論了‧看过一部分、觉得不似是近代的文章‧也不是出自资深发烧友的手笔‧但作为对HIFI及器材的基本認識,资料却很宝贵‧
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16#

俄~~~~~~~~~~~~~~~~~~~~~~~~~~~没看懂,哪位翻译一下:)
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17#

坛上的E文高手翻译出来益街坊啦。
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18#

17.0 The Press:
17.1 Which magazine should I read?
17.2 Which reviews are better?
17.3 Is Consumer Reports right?

17.1 Which magazine should I read?
Which ever one you like. None are absolutely objective. Here's a list of some common ones:

        Audio Amateur ($20/yr 4 issues) (Do-it-yourself)
                Box 576
                Peterborough NH  03458 USA
                603-924-9464
        Audio Critic (US $24/yr 4 issues) (High-end)
                PO Box 978
                Quakertown PA  18951 USA
                215-538-9555 or 215-536-8884
        Audio Magazine (US $24/year 12 issues.  Mid-fi)
                Subscription Office: PO Box 53548
                Boulder CO  80321-2548 USA
                800-274-8808, 303-447-9330
                Editorial Office: 1633 Broadway
                New York, NY  10019
                212-767-6000
        Audio Observatory (US $15/year 12 issues)
                22029 Parthenia Street
                West Hills, California  91304
        Audiophile Voice ($18/year 4 issues)
                Subscriptions: Michael Tantillo
                        132 Beach Avenue
                        Staten Island 10306 USA
                        Phone 718-351-9365
                Editorial Office: 2001 Palmer Ave Suite 201
                        Larchmont, NY  10538-2420 USA
                        Phone 914-833-1417
                        FAX 914-834-4070
        Bound For Sound (US $18/yr 12 issues) (High-end)
                220 North Main St
                Kewanee IL  61443 USA
                309-852-3022
        Car Audio and Electronics ($19.95/year 12 issues)
                Avcom Publishing Ltd
                21700 Oxnard Street
                Suite 1600
                Woodland Hills CA  91367 USA
                818-593-3900
        CD Review (Music Reviews; all tastes, only CDs.)
                $19.97 per year 12 issues
                PO Box 588
                Mount Morris IL  61054 USA
        Glass Audio ($20/yr 4 issues) (Do-it-yourself, tubes)
                Box 576
                Peterborough NH  03458 USA
                603-924-9464
        Hi-Fi Choice (Mid-end. Comparative reviews with graphs,
                        tables, and subjective commentary;
                        'Buying Guide' section)
                Dennis Publishing Ltd.
                14 Rathbone Place
                London, W1P 1DE, UK
                +44 71 631 1433
        Hi-Fi News and Record Review (Broad. Good new record
                        reviews. Good equipment measurements)
                Subscriptions Department
                        Link House Magazines Ltd
                        1st Floor
                        Stephenson House, Brunel Centre
                        Bletchley, Milton Keynes MK2 2EW, UK
        Hi-Fi World  (Friendly, lower-mid-end magazine)
                (reviews and "how things work" articles)
                Audio Publishing Ltd
                64 Castellain Rd
                Maida Vale
                London  W9 1EX, UK
                +44 71 266 0461
        In Terms Of Music  (Emphasizes music reviews, new)
                PO Box 268590
                Chicago, IL 60626  USA
                312-262-5918
        International Audio Review (US $38/yr, 12 issues?)
                2449 Dwight Way; Box 4271
                Berkeley CA  94704 USA
        Positive Feedback (US $25/yr 6 issues) (high-end)
                Oregon Triode Society
                4106 N.E. Glisan
                Portland OR 97232 USA
                503-235-9068
        Sound Practices (US $20/yr 4 issues) (Do-it-yourself)
                Box 180562
                Austin, TX   78718
                (512) 339-6229    Voice/Fax
                72411.533@compuserve.com
        Speaker Builder ($25/yr 6 issues) (Speaker projects)
                Box 576
                Peterborough NH  03458 USA
                603-924-9464
        Stereophile (US $35/yr 12 issues) (High-end)
                208 Delgado
                Santa Fe NM  87501 USA
                800-238-2626 or 505-982-2366
        Stereo Review (US $6.97/yr 12 issues.  Lower end/mass
                        market)
                Subscription Office: PO Box 52033
                Boulder CO  80323-2033 USA
                Editorial Office: 1633 Broadw
                New York, NY  10019
                212-767-6000
        The Absolute Sound (US $46/yr 8 issues) (High-end)
                Subscription Center: Box 6547
                Syracuse NY  13217 USA
                800-825-0061
                Editorial Office: 2 Glen Avenue
                Sea Cliff, NY  11579
                516-676-2830
        The $ensible Sound (US $20/yr 4 issues) (Mid/High-end)
                403 Darwin Drive
                Snyder NY  14226 USA
                716-681-3513 or 716-839-2199
        Ultra High Fidelity (UHF) (High end, no advertising)
                Box 65085, Place Longueil
                Montreal PQ  J4K 5J4  Canada
                514-651-5720
        What Hi-Fi (Mid-to-high End; comparative, subjective
                        reviews. Contains it's own buyer's guide
                        with recommendations)
                 Haymarket Trade & Leisure Publications Ltd
                 38-42 Hampton Road
                 Teddington, Middlesex, TW11 0JE, UK
                 +44 81 943 5000
                 US Enquiries should go to:
                        Eric Walter Associates
                        Box 188
                        Berkeley Heights NJ  07922 USA
                        201-665-7811

17.2 Which reviews are better?
Some reviews are so colorful and exciting, that they make great journalism and fun reading. Lets ignore these for now, even though they have their place.

Beware of reviews from magazines that advertise the same product. The likelihood of bias is too high. Unfortunately, that rules out 99% of the reviews in magazines.

Stereo Review has a bad reputation for loving everything made by every advertiser. Even high-end journals such as Stereophile and The Absolute Sound can be influenced.

A classic example of misleading reviews occurs with equipment submitted to a magazine for review. The manufacturer may send the editors a carefully built, adjusted piece for review. The magazine will honestly rave about it. The manufacturer will then send the design off-shore for more economical manufacture and assembly, and the quality will suffer. Lower quality components will be substituted for prime parts. Adjustments will be made to wider tolerances or will not be made at all. The design may be completely changed to make it more manufacturable. You will unknowingly get a completely different piece than reviewed.

Home auditions with one or two candidates from each of a few dealers are your best guide to be sure that you get what you want and pay for.


17.3 Is Consumer Reports right?
Consumer Reports is the most objective testing lab we have ever found. Unfortunately, they are also the world's least specialized testing lab. They market their testing to the average consumer. The average consumer will not hear some of the subtle differences which audiophiles hear. For that reason, Consumer Reports ignores issues that others feel vital.

Consumer Reports also insists on basing their audio testing predominantly on lab measurements. Although lab measurements do tell many differences between devices, interpreting lab measurements for best sound is difficult or impossible. For example, it is very hard to compare two speaker frequency response curves and tell which will sound better. Some $3000 speaker frequency response curves look worse than some $600 speaker curves, even when tested in the same setup. On the other side of the issue, Consumer Reports has improved its test methods, and will continue to improve. Expect the accuracy of their reviews to improve with time.

The Consumer Reports frequency-of-repair data base is larger than any similar data base published and can be trusted as well as any statistic.


Back to main index - Continue to 18.0 Retail
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19#

英文考试我每次都不及格。
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20#

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母,我都认得,就是不知道讲什么。
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