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 What should I listen for when evaluating a turntable, tape decks or CD player?
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For tape decks and turntables, beware of speed variations (wow and flutter). A good check for
this is Richard Strauss'
"Also Sprach Zarathustra" (Pa.... pa...pa.......... PA!PA!) , which has a long, low, sustained organ note that comes in well before the main theme starts, and is held through the first movement. Concentrate on that. Make sure it doesn't wobble or warble. There's also a good passage at the beginning of Pink Floyd's "The Wall", but it doesn't go on as long, so you've got less time to think about it. Tape decks are prone to losing high-frequency notes, so pick something you like which has lots of treble, and make sure it is clear. The sound of a turntable is largely dependent on the cartridge mounted on it. Make sure to listen to a table with a cartridge similar to what you're buying, and not one in a different price bracket. If possible, audition the turntable with the same arm and cartridge, so that you will experience potential cartridge/arm interactions, too. Most cartridges work better with one arm than another. Treat the tone arm/cartridge pair as a system, rather than independent parts.
For CD players, test it using piano music. See if the high notes sound tinny. Also, try something which has some soft parts, not the same as turning the
volume down. Distortion for CD players (as for other devices) is measured at a high output, but in fact in CD players (unlike others) it's likely to be worse in soft passages of music. Most classical recordings contain a suitable soft passage. Most rock music won't.
Distortion in CD players, if you want to call it that, is a function of the granulation noise, or time-delay pre-echo that can come out of the filtering. To listen for this, use
material that is rich in high-order harmonics, such as brass music. Unfortunately, you can't reliably predict how a CD player will
sound by looking at specifications, features, or the technology it uses. If you want to know how a player will sound, you MUST listen to it.
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Are some discs better than others? |
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Some recordings are better than others. Some artists are better than others. Some recording
engineers are better than others. Some microphones are better than others. Some music is better than others.
Ignoring the above, there is some difference between discs. Some of the very
earliest discs were badly made and deteriorated with time. The technical problems that caused those problems have been solved.
Some "gold" discs are available which are advertised to
have better life
and quality than common "aluminum" discs. These sell for an extra US $15 or more per disc over the cost of the same music on a common disc. Studies have shown that there is an advantage to glass-encased, gold platters for archiving computer data that is not error tolerant and will need to be stored for many tens of years.
Some discs seem to have pinholes in the aluminum, which are visible when
the disc is held up to a strong light. However, these discs play fine and last very well, so the effect of these pinholes is probably nil. Some have performed studies counting errors on various discs with various players. They found that, in general, the error count was consistent from one player to another. Also, in general, most discs have a low, consistent error rate which is perfectly correctable using the redundant data stored on the disc. This study did find that one group of discs had a higher error rate than all of the rest. This group was the promotional discs, also called "music samplers" given away by music companies to introduce you to their family of artists and performers. Despite these higher error counts, these discs still played fine.
If there is no abusive handling involved, I have rarely heard of a disc that degraded with time. Of the few that have existed, they tended to be from one of the bad batches mentioned
earlier.
There is no doubt that some discs are mastered better than others. Some are badly mixed. Some are so badly recorded that there is noticeable clipping. Some are made from damaged master
recordings. CD technology is no guarantee of good music or of a good recording.
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Are CDs better than LPs? |
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Some excellent recordings are mastered digitally, and sound great on LPs. This suggests that THERE
IE NOTHING INHERENTLY BAD ABOUT DIGITAL.
Some find that LPs sound better than CDs. Advocates of LPs claim that the digital to analog (D/A) converter in home CD players isn't up to the quality of
the information on the disc. They also claim that the analog electronics in a home CD player can be poor.
Some believe that CDs do not sound like LPs because the CD does not have
the frequency response errors, the distortion, or the stereo separation problems of LPs.
In general, though, there are good and bad CD players, just as there are good and bad turntables,
cartridges, and tone arms. Any ultimate comparison
would require ultimate equipment, which is unaffordable. In moderately priced systems, there will be some signal damage from the turntable system and some signal damage from the CD player.
LP lovers often learn the nuances of cartridge selection, record care, and
even turntable and tonearm adjustment. They have found that the turntable will sound different if the arm height is adjusted, if the cartridge angles are changed, and if the tonearm wire is moved. CDs do not offer as many avenues for the home experimenter.
However, Audio Amateur Magazine has published modification projects for CD players; particularly for Magnavox 560 and similar European players. Audio Magazine has also published such articles.
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What type of turntable should I buy? |
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Despite improvements in motor technology, most great turntables use belt drive. Rubber roller (idler)
drive sounds the worst.
Select a turntable with a very heavy platter for the least wow and flutter. Give the platter a rap with your knuckle. It should not "ring" like a cymbal. It
should feel and sound dead.
Also look for a turntable that has good isolation from base to stylus. With the amp on and the turntable selected, but with the turntable motor off, put an
old record on the turntable, lower the stylus onto the record, and then tap
the edge of the base. Not too hard, you don't want to send the arm flying. At worst, you should hear (through the speakers) a quick 'thump' followed by silence; if you're lucky, you'll hear nothing at all. If the sound continues beyond a quick 'thump', the mechanical isolation is not great, and you might want to look at some other make. To perform this test with some turntables, it will be necessary to unplug the turntable power cord.
If the turntable has a tone arm, try to evaluate the arm, too. A good arm should be adjustable in height. A good arm should allow cartridge adjustments. A good arm will be very rigid and
have no bearing play. A good arm should accommodate a wide range of cartridges. Despite this, some arms work better with high compliance cartridges, while others are at their best with low
compliance. Ask.
The original AR Turntable was very well received when it was first made, and the current AR Turntable is still very respected for its price ($450 + arm). Turntables made by
Denon, Dual, Linn, Mitchell, Oracle, Pro-Ject, Rega, Sota, Thorens, and VPI are also recommended, but can cost more. If you want a turntable on a budget, consider the Project Debut.
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What phono cartridge should I buy for my older turntable? |
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The $30 Grado ZTE+1 is a great value for any home user but a purist. For the purist, there are still many
choices, both moving coil and
moving magnet. Each sounds slightly different, and has its individual strengths. Moving Magnet (MM) cartridges tend to have higher output than Moving Coil (MC) cartridges, with exception. Low Output Moving Coil cartridges require unusual pre amplification. Check with a dealer before buying one. Some proven candidates:
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~US $85 (MC High Output, Std Mount)
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~US $110 (MC Low Output, Std Mount)
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Will phono cartridges still be around ten years from now? |
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Most likely, there will still be cartridges available, but not in the variety available ten years ago.
They will become "Special Order" in some stores and unheard of in others.
"Pro" or "DJ" cartridges will stay available in good supply,
"Audiophile" cartridges will stay available and very expensive, "Mid-line" cartridges will
become very scarce, and a few "Budget" cartridges will remain available in copious supply. At the same time, some makers will drop their cartridge lines completely.
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Will LPs still be around ten years from now? |
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There is a strong movement of collectors and purists who will keep their collections and buy good
used discs. Count on these people to keep the used disc market hot for 25 years longer.
As for new music, less is being pressed today than 20 years ago. Many popular artists are being
released on LP in parts of Europe, but availability is dependent on country. One person said that many new LPs are available in Spain.
LP sales have increased recently in Japan and in
the UK. Polydor is now re-releasing older recordings on vinyl, and will continue to press them as long as it is profitable. Likewise, there are several re-releasing projects in
Japan. Some are for Jazz collectors and others are for pure analog as well as classical music lovers. They are selling the LPs by subscription, with shipments every 2 or 3 months. Each release includes about 20 titles. Japan has released over 100 LPs this way last year.
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What about CD green or black pens? |
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CD player "reads" information on the disc with a laser light beam. Some believe that if you put
a green stripe on the very perimeter of the disc, then the light beam will not reflect around inside the disc and will more clearly pick up the data.
Scientific studies of the data coming
off of the disc have failed to show any difference between a virgin disc and a green painted disc. But many have performed uncontrolled tests with positive results.
Using the Auric Illuminator Black Pen
has proven to be very significant in sound improvement.
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What about CD stabilizer rings? |
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Scientific studies of the data coming off of the disc have failed to show any improvement going from a
virgin to a ringed disc. But use of CD stabilizers has proved to increase the focus of sound stage imaging to various degree.
The data coming off of the disc is a serial string of ones and zeros. If
this bit stream has jitter, then it may reach the D/A converter out of sync. If this happens, then the actual analog signal recreated will have jitter, and won't be perfectly true. The vendors of stabilizer rings say that using these rings will reduce jitter and make a more perfect signal. Vendors also claim that the rings can increase the mass of a disc, making it spin more smoothly, and reducing transient load on the power supply from the motor.
Some players will not play discs that have stabilizer rings on them. The clamp can't handle the thickness.
Other players play ringed discs, but do not play them well, because the disc motor was not built for the added load.
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What about CD treatments like Auric Illuminator? |
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Auric Illuminator has proven to be very effective in sound improvement during listening tests. It is safe and requires only one treatment.
Some treatments that contain chemicals will definitely damage the disc, but not the Auric Illuminator
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There are many theories on what treatment can do to a disc. One is that it reduces static which will
attract the delicate head of the laser detector to the disc. Another theory is that the cleaner will fill voids in the disc with
silicone, thereby making it easier to read by reducing diffraction effects.
Scientific studies of the data coming off of the disc have failed to show any difference between a virgin disc
and a treated disc.
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Are 1-bit CD players better than multi-bit players? |
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There are some excellent sounding 1-bit players and some excellent sounding multi-bit players. Some feel
that the 1-bit technology has more future because
it can be improved with the rapidly improving digital technology, while the multi-bit players improve with slowly improving analog technology. Multi-bit also has its advocates.
All of the various
D/A converters try to do the same thing, and try to achieve the exact same ideal performance. How well they succeed is more a
function of their skill and the quality of the parts that they buy than the technique that they use. In other words, the architecture of a D/A converter is less important than the quality of its implementation.
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Are three lasers better than one in CD players? |
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Some players have one beam, some three. All use one laser diode to generate the beam. Three-beam is just a
different method for doing track alignment. Neither is better than the other.
There are good 1-beam players and good 3-beam players. Both have their merits.
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Are the deals (CD/Accessories) on 1388.com good? |
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Yes. All things sold in 1388.com are first auditioned by Joe Lee and Jon Wong. If they do not work, we
will not recommend! Due to bulk purchase and special recommendations, the price are good deals for 1388.com members.
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What should I do if there is a problem dealing with 1388.com? |
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The number to reach 1388.com is +65-569 5711. Call and things will be sorted out. We have o complains
about delivery and the quality of goods so far.
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How do I find good deals on 1388.com? |
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Check Joe Lee Says every week, or log into 1388.com for the latest news. You should comb thru pass issues
as well.
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How do I get the most out of 1388.com? |
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Register as member and log in often.
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What are the differences between multibit and Bitstream/MASH Analogue to
Digital converters (16-bit vs 1-bit CD players)? |
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Audio data is stored on CD as 16-bit words. It is the job of the digital to analogue converter (DAC) to
convert these numbers to a varying voltage. Many DAC chips do this by storing electric charge in capacitors (like water in buckets) and selectively emptying these buckets to the analogue
ouput, thereby adding their contents. Others sum the outputs of current or voltage sources, but the operating principles are otherwise similar.
A multi-bit converter has sixteen buckets
corresponding to the sixteen bits of the input word, and sized 1, 2, 4, 8 ... 32768 charge units. Each word (ie
sample) decoded from the disc is passed directly to the DAC, and those buckets corresponding to 1's in the input word are emptied to the output.
To perform well the bucket sizes have to be
accurate to within +/- half a charge unit; for the larger buckets this represents a tolerance tighter than 0.01%, which is difficult. Furthermore the image spectrum from 24kHz to 64kHz must
be filtered out, requiring a complicated, expensive filter.
Alternatively, by using some digital signal processing, the stream of 16-bit words at 44.1kHz can be transformed to a stream of
shorter words at a
higher rate. The two data streams represent the same signal in the audio band, but the new data stream has a lot of extra noise in it resulting from the word length reduction. This extra noise is made to appear mostly above 20kHz through the use of noise-shaping, and the oversampling ensures that the first image spectrum occurs at a much higher frequency than in the multi-bit case.
This new data stream is now converted to an analogue voltage by a DAC of
short word length; subsequently, most of the noise above 20kHz can be filtered out by a simple analogue filter without affecting the audio signal.
Typical configurations use 1-bit words at
11.3MHz (256 times over-sampled), and 4-bit words at 2.8MHz (64 times over sampled). The former requires one bucket of arbitrary size (very simple); it is the basis of the Philips Bitstream range
of converters. The latter requires four buckets of sizes 1, 2, 4 and 8 charge units, but the tolerance on these is relaxed to about 5%.
MASH and other PWM systems are similar to Bitstream, but
they vary the
pulse width at the ouput of the digital signal processor. This can be likened to using a single bucket but with the provision to part fill it. For example, MASH allows the bucket to be filled to eleven different depths (this is where they get 3.5 bits from, as 2^(3.5) is approximately eleven).
Lastly it is important to note that these are all simply different ways of
performing the same function. It is easy to make a lousy CD player based around any of these technologies; it is rather more difficult to make an excellent one, regardless of the DAC technology employed. Each of the conversion methods has its advantages and disadvantages, and as ever it is the job of the engineer to balance a multitude of parameters to design a product that represents value for money to the consumer.
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What is the best under-US$200 CD player? |
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The Philips or Marantz type CD players are well known. Some believe that for sound, an
under-US$200 Philips is as good as any in its price range. Be sure to listen for yourself before you buy. Avoid players that do not have warranty.
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What is the best under-US$500 CD player? |
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Some recommend Rotel while others recommend Marantz. Pioneer are good as well.
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What's wrong with the CD longbox? |
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Some CDs are
sold shrink wrapped in a square plastic storage box known as the "jewel" box. This is the ideal packaging for CDs. It has almost no unusable components and adequately protects and displays the disc. The shrink also implies that the disc is new and unopened, but shrink can never assure a new disc.
Some CDs are still sold in a cardboard box that is more than 2X the size of the jewel box. This "long box" is ecologically wasteful and useless. It rarely contains additional
information about the disc or the artists. Its primary purpose is to discourage theft in retail stores, but it is even poor at that. These boxes are bad.
Some stores use a reusable plastic
long box. When you buy a disc in one of these boxes, you take the disc and jewel box with you and leave the plastic long box with the cashier for reuse. Not perfect, but a good compromise.
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