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- From: Bob Neidorff <neidorff@uicc.com>
- Subject: FAQ: rec.audio (part 3 of 4)
- Message-ID: <faq3_763393701@uicc.com>
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- Summary: Answers to common questions about audio equipment, selecting,
- Originator: recmusic@cygnus
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- Date: Mon, 14 Mar 1994 20:04:19 GMT
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- Archive-name: AudioFAQ/part3
- Last-modified: 1994/2/15
- Version: 1.13
-
- 12.0 High Fidelity Systems
- People frequently use the term "Stereo" to refer to a sound
- reproduction system. To be more accurate, we will use the term
- High Fidelity System to refer to a pile of equipment including
- at least one source, at least one amplifier, and at least one
- speaker. Common sources are turntables, CD players, tape
- players, tuners, and receivers.
-
- 12.1 What is a receiver?
- A receiver is a tuner, power amplifier, and preamp combined. A
- common receiver has inputs for a turntable, a CD player, a tape
- deck, and perhaps one or two other sources. It has selector
- switch(s), tone controls, and a volume control. A receiver may
- have outputs for two speakers, or for more.
-
- 12.2 What is a tuner?
- A tuner is a radio receiver which can not directly connect to
- speakers. Sometimes, the radio in a tuner is higher quality
- than the radio in a receiver. A tuner may or may not receive
- the AM broadcast band, but 99.999% will receive the FM broadcast
- band. Some also receive short wave bands, frequencies used
- for long-distance rather than for local commercial broadcasts.
-
- 12.3 How should I go about selecting a system?
- If you're looking to buy something, the first step is to figure
- out what you can spend. If you're looking for a whole system,
- this gets tricky, because you have to allocate amounts for the
- different components. The most popular current rule-of-thumb
- for a single source system (speakers, amp, 1 something-player)
- is to divide the money about equally among the three parts. If
- you want several players, you'll have to decide whether they are
- all equally important, and so deserve the same amount of money;
- or whether some are less important, in which case you can spend
- less on them and put the savings elsewhere.
-
- This rule isn't hard-and-fast. It's just meant as a starting
- point so you don't have to listen to every possible combination
- of equipment. If you are building around a CD player, you might
- spend a bit less on the player and a bit more on the speakers.
- If you are buying turntable (or something else which plays by
- physical contact) on the other hand, it might be good idea to
- put a bit extra into the player. The reason for this is that if
- you skimp on the turntable, then when you come to buy a better
- one you may find that your records have been worn out by the
- cheap player. If you skimp on the speakers, on the other hand,
- then when you can afford better speakers the music will still be
- there on your records.
-
- See also 9.1, 9.2, and 11.1 for information on what to listen
- to and what to listen for when evaluating speakers, turntables,
- CD players, tape recorders, and systems in general.
-
- 12.4 How can I improve the sound of my stereo?
- The cheapest improvement you can make, and perhaps the most
- effective, is to position your speakers carefully and correctly.
- See 13.1, below. This will improve the frequency response
- flatness, making it easier to hear every instrument and voice.
- Setting speaker position correctly can also improve the
- three-dimensional recreation of a stereo image.
-
- 12.5 Do I want a combo system or separate components?
- Combo systems used to be cheap jokes; that's not always true
- now. Some sound very nice; there are even some made by
- "audiophile" companies, and they sound even nicer. They've got
- lots of advantages. They take up less space. The controls tend
- to be well-integrated, especially if they are remote-controlled.
- Therefore, they are easy to operate; this can be a major plus if
- some of the people who'll use it are afraid of, or not very good
- at, technology. Also easy to set up, and don't leave millions
- of wires dangling all over everywhere.
-
- If you do go for a combo, get a brand name; either an audiophile
- company, or a good "consumer electronics" company. Brand-X
- combos are generally overpriced and unpleasant. If possible,
- buy it where you can listen to it first, such as a "real" hi-fi
- shop. Mid-range hi-fi shops sell combos, as a way of
- introducing beginners to quality sound.
-
- In most good combos, the speakers are the weak link. If you do
- go for a combo, you can almost always improve the sound
- drastically by buying a set of better speakers. Better speakers
- start in the $100-$200 price range. Some of the best combos
- come without speakers, forcing you to do this. A good combo
- with replacement speakers will give you very pleasant music.
-
- Sounds good, you say, so why do people bother with components?
- Well, you can get better sound with a component system -- but
- usually at the expense of convenience and size. A good
- component system will normally require a mixture of boxes from
- different makers to get the best results, so you've got to spend
- more time listening to things. However, if you listen to your
- music seriously, then the performance of a component system is
- the reward for that extra work.
-
- Components are harder to set up and operate. However, as noted,
- you can get better sound. You also get more flexibility. If,
- for example, you decide you want a better CD player, you just
- replace the CD player. With a combo system, you've got to
- replace the whole system. If your component tape deck breaks,
- you can remove it from the system and take it in for repair or
- replacement. With a combo, the whole system has to go in for
- repair or be replaced.
-
- When you want to add some new recording medium to your system
- (laserdisc, VCR, DAT, DCC, MD, ...), if you've got components
- you just go buy the appropriate box. Many combo systems do not
- have places (or many places) to attach extra bits, so again you
- could be looking at replacing the whole thing. With a component
- system, you can add a turntable; most modern combos can't cope
- with turntables any more. Do you have a record collection?
-
- If you're really not sure, components are the safer bet; if
- you're going to make a mistake, that's probably the better way
- to be wrong. But, if you're sure that a combo would be best
- for your needs, it can be a totally reasonable choice.
-
- Now, some people may be tempted by one-maker 'component sets',
- particularly the modern, miniature ones. They tend to be
- equivalent to combos. Most use non-standard connections, rather
- than the normal twin phono plug, so that it's likely you can't
- swap or add components anyway. Even where they use standard
- interconnects, they may rely on non-standard interconnections
- for control purposes. In a few cases, they also rely on sharing
- power, with a power supply in only one of the boxes and the rest
- taking low-voltage connections from that. And, no one maker
- makes the best everything. By default, assume that they will
- have the same disadvantages (and most of the same advantages) as
- combos. If it's important for it to work with "standard"
- components from other makers, be sure to ask before you buy.
-
- And, if you're in doubt, go for separate components.
-
- 12.6 How can I get better FM radio reception?
- A. Use a (better) antenna. (See 12.7 and 12.8 below)
- B. Use a (more) directional antenna. (See 12.7 and 12.8 below)
- C. Aim your directional antenna. Rhombics are ungainly to move,
- but Yagis and dipoles are small enough to point right at
- the station. With the dipole, to tune in a station to
- the East, run the antenna North-South. With a Yagi,
- point the individual elements North-South with the
- smallest element on the East end.
-
- 12.7 How good are these compact FM antennas?
- For receiving, small is ugly. The bigger the antenna (all else
- equal) the better. Of course, all else is never equal, but
- these fancy, expensive mini antennas tend to be awful. Some
- compensate for their small receiving structure with a small
- antenna signal amplifier. However, the quality of that
- amplifier is often no better than the quality of the amplifier
- in your tuner or receiver, so the antenna just gives you a
- stronger signal, complete with stronger noise.
-
- All of that said, some compact FM antennas can work better than
- a simple dipole in some situations. They tend to have an
- internal amplifier, which helps with weak signals. Some are
- directional. Some aren't. If possible, be sure that whatever
- you buy can be returned for a refund if it doesn't work out well
- for you.
-
- 12.8 What makes the best FM radio antenna?
- Although there is no "best" antenna for everyone, one of the
- most directional is the "rhombic". Being very directional, this
- antenna can select one weak station out of many strong ones, or
- one group of stations originating from a general direction.
- This antenna is very long, and made up of four pieces of wire
- with feedline at one end for antenna connections and a resistor
- at the other for termination. Rhombics for FM broadcast band
- use are at least 15 feet (4.5 meters) long, but can be made
- fairly narrow, less than 3 feet (1 meter) wide. A more narrow
- antenna will be more directional. A longer antenna will give a
- stronger signal.
-
- Another very directional antenna is the "yagi", which looks just
- like a common TV antenna. You can even use a common TV antenna
- as a very good FM antenna. The FM and TV bands are very close
- together. It has the advantages of being cheap, directional,
- and easy to rotate.
-
- One of the simplest and easiest to make antennas is the folded
- dipole, made from 300 ohm twin lead. It is approx. 58" long.
- This antenna is surprisingly good for receiving signals in a
- moderately strong signal area. Folded dipoles come with many
- tuners and receivers as a standard accessory. They are also
- available for approximately $2 at audio and department stores.
-
- Whatever antenna you have, you can often get it to work better
- for specific stations by moving it. In the case of the folded
- dipole, sometimes it works better vertically, and other times it
- works best horizontally. Sometimes, you can get that one
- elusive station to come in perfectly if you bend the two ends of
- it at funny angles. Don't be afraid to experiment. One
- warning. As atmospheric conditions change, the best antenna
- placement may also change.
-
- An excellent reference book on antennas is printed by the
- American Radio Relay League (ARRL). It is called The ARRL
- Antenna Book. Currently in its 16th edition, it is a 736
- page large, illustrated paperback. It costs $20 plus s/h.
- It has fairly complete antenna theory, practical information
- such as charts, drawings, comparisons, and tips on construction
- and adjustment. The ARRL is founded and chartered as a
- non-profit organization to better amateur radio, and antennas
- are a vital part of amateur radio.
- American Radio Relay League
- 225 Main Street
- Newington CT 06111 USA
- 203-666-1541
-
- Also useful:
- Practical Antenna Handbook by Joseph J. Carr
- Tab Books #3270/McGraw Hill - ISBN 0-8306-3270-3
-
- 12.9 What about power line conditioners?
- Each home and each outlet has slightly different power line
- impedance and power line noise. Each amplifier is effected by
- power line impedance and power line noise differently. Power
- line conditioners try to reduce this line noise. Some also
- change the power line impedance in a way which is supposed to be
- better. We will leave it to your ears to decide if these
- devices help the sound of your system enough to justify their
- expense.
-
- 12.10 How can I reduce vibration sensitivity?
-
- 12.11 What equipment can I buy that is 100% made in the USA?
- There are many lines of equipment that are carefully hand
- crafted in the USA. Unfortunately, these systems are usually
- the high-end ones. Some US companies also make gear in the
- far east. When in doubt, ask. Some US audio manufacturers are:
- Adcom (some made in Japan)
- Audio by Van Alstine
- Audio Research
- California Audio Labs (CAL)
- Carver (some made in Japan)
- Jeff Rowland
- Krell
- Mark Levinson
- McCormack
- McIntosh
- Parasound
- Proceed
- PS Audio
- Spectral
- Waida
-
- 12.12 Should I buy "xxx"? Which is better: "yyy" or "zzz"?
- We can provide facts and opinions (and you get to decide which
- is which :-), but we can't recommend if, or which way, you
- should jump, because we don't know what your priorities are.
- (That won't stop us from trying, though!) For example, if you
- are considering a used item at a low price vs. a new one at a
- higher price, one of us might say "go for the new one because
- of the warranty", when another would say that you can fix it
- yourself if it breaks. They're both right.
-
- This also applies to speakers. One may have very good, flat
- bass, but only go so low, where the other may go lower, but
- have less flat frequency response. Which is better? Depends
- on the buyer. Good speakers are carefully designed to
- achieve a balance of performance that matches the priorities
- of the designer. Some designers put much of their budget into
- appearance. Some designers put their budget into very high
- efficiency. Others strive for the smallest box which can
- deliver an acceptable low frequency performance. Do you
- really want people on the network making that decision for you?
-
- 13.0 Listening Rooms and Houses
-
- 13.1 How should I place speakers in my room? What size room is best?
- You are after two important, distinct goals: flat frequency
- response and good three-dimensional image. At your disposal is
- the room size, the room shape, speaker height, speaker
- placement, listening position, and room treatments. Even though
- good speakers are essential to good sound, room effects are also
- extremely important. In many cases, the differences in room
- effects will be more noticeable than spending twice as much on
- speakers!
-
- For smoothest bass response, a listening room should be as large
- as possible, have dimensions as unrelated as possible, and
- should be optimally damped. Although nothing is ever ideal,
- there are a few room dimension ratios that are better for
- listening rooms:
- Height Width Length
- 1 1.14 1.39
- 1 1.28 1.54
- 1 1.6 2.33
- If your room isn't shaped like that, don't worry. These
- effects are not major.
-
- Also for smooth bass response, woofers should be at distances
- from the nearest three room boundaries that are as different as
- possible. In some cases, the line dividing the listening room
- into left and right halves must be considered a room boundary.
- Also, for smooth bass response, the listener's ears should be
- at distances from the nearest three room boundaries that are
- as different as possible.
-
- All of this is essential because a wall near a speaker boosts
- the bass from that speaker at some frequencies. If a speaker
- is the same distance from three walls, then some frequencies
- will be emphasized much more than others, rather than slightly
- more.
-
- For best three-dimensional image, a listening room should have
- good symmetry about the plane between the two speakers. This
- means that if one speaker is in a corner, the other speaker
- must be in a corner. If this symmetry is not right, the first
- reflection from the wall behind one speaker will be different
- from the first reflection from the wall behind the other speaker
- and critical parts of the stereo signal will be damaged.
-
- Also, no large object should block the path from speakers to
- listener or from speaker to speaker. Speakers should be
- elevated so that tweeters are at listener ear height. The
- distance between speakers should be no greater than the distance
- from each speaker to the listener. Finally, the tweeters should
- be aimed at the listeners.
-
- A normal box-shaped listening room with bare walls will have
- "slap echo" which will reduce intelligibility. A good cure is
- randomly-placed wall hangings consisting of small rugs spaced
- an inch or so away from the wall to increase sound absorption.
- Another cure is convex-shaped art objects on the walls to
- disperse harmful reflections. If money is available, commercial
- room treatments such as "Tube Traps" and "RPG Diffusers" are
- also valuable, but many of the benefits of these exotic devices
- are available with simpler techniques.
-
- As a general rule, in a good room, speakers and listener can be
- close to room boundaries with minimal adverse effects. In a bad
- room, a good strategy is to place both speakers and listener as
- far away from room boundaries as possible.
-
- An excellent starting point for speaker placement is to measure
- the listening room diagonal dimensions. Divide that measurement
- by three. Put each speaker that distance from a corner, on the
- room diagonals.
-
- I-----------------------------------I
- I I
- I L I
- I I
- I S S I
- I I
- I-----------------------------------I
-
- Place your listening position midway between the two speakers
- and approximately half way from the speakers to the wall. Be
- sure that there is nothing in the "triangle" formed by the
- listening position and the speakers.
-
- Try this and then move things 12" (30cm) at a time to see if
- you can improve the sound. Your ears will be a better guide
- than any commonly-available instruments. To keep track of
- what you are doing, take notes. To remember exactly where
- you put the speaker on the floor, a practical trick is to
- mark the floor with a sewing needle and thread.
-
- 13.2 How do I wire a house for sound?
- A fundamental principle of physics is that the farther a signal
- travels, the more the signal will be degraded. Translate this
- to mean that the shorter the wire, the better. Understanding
- this, the idea of running speaker cable between every room of
- the house isn't as attractive as it first seems.
-
- If you still decide to wire your house for sound, you should do
- it at the same time you're wiring for telephone and electricity.
- It is possible to wire a house after the walls are closed, but
- it becomes very difficult.
-
- It is economical to use common house wire (Romex, UF, NM, etc)
- for speaker wire in the walls, but this may violate building
- codes. Check with an electrician or inspector first. It will
- also confuse future electricians, so label the wire clearly, all
- along its length.
-
- If you want to make your house like a recording studio, it is
- best to use the techniques of recording studios. When studios
- run long lengths of sound cable from one room to another, they
- drive the cable with 600 ohm line amplifiers. They also use
- shielded, twisted-pair cable. They only connect the shield at
- one end of the cable. Finally, they use balanced inputs at the
- other end of the cable.
-
- 13.3 Where can I read more about listening room construction and tuning?
- "Building a Recording Studio" by Jeff Cooper
- Mix Bookshelf
- "Handbook for Sound Engineers"
- "The Master Handbook of Acoustics" by F Alton Everest
- "Sound Engineering 2nd Edition" by Don and Carolyn Davis;
- Howard W. Sams & Co. (C) 1990
- "Good Sound" by Laura Dearborn
- Introductory, but clear and accurate
- "Sound Recording Handbook" by John M. Woram
- Howard W. Sams & Co. #22583
- Excellent General Reference
- "Audio Technology Fundamentals" by Alan A. Cohen
- Howard W. Sams & Co. #22678
- Overview of Audio Theory
- "Introduction to Professional Recording Techniques"
- by Bruce Bartlett
- Howard W. Sams & Co. #22574
- "Modern Recording Techniques" by Hubar and Runstein
- Howard W. Sams & Co. #22682
- "Sound Studio Production Techniques"
- by Dennis N. Nardantonio
- Tab Books
- "The Uneasy Truce Between Music and the Room"
- F. Alton Everest
- Audio, February 1993, Pgs. 36-42
- "Coloration of Room Sound by Reflections"
- F. Alton Everest
- Audio, March 1993, pgs. 30-37
-
- 13.4 What is white noise? What is pink noise?
- "White noise" is characterized by the fact that its value
- at any two different moments in time are uncorrelated.
- This leads to such noise having a flat power spectral
- density (in signal power per hertz of bandwidth), and is
- loosely analogous to "white light" which has a flat power
- spectral density with respect to wavelength.
-
- Pink noise has flat power spectral density per PERCENTAGE
- of bandwidth, which leads to a rolloff of -3 dB/octave
- compared with white noise.
-
- There are many reasons for using pink noise in audio testing.
- One is that music has an average spectral content much closer
- to pink noise than white noise. Another is that pink noise
- can be readily measured with constant Q bandpass filters and
- naturally leads to flat plots on logarithmic frequency scales
- - which correspond to the equally tempered musical scale.
-
- Pink noise is often used with 1/3 octave band filters to
- measure room acoustics. This idea has merit since 1/3 octave
- is a convenient number near the limit of our ears ability to
- detect frequency response irregularities, and because
- averaging measurements over 1/3 octave bands smooths out the
- numerous very narrow peaks and dips that arise due to
- standing waves in rooms.
-
- Another term you'll hear about is Gaussian noise - this is
- noise with a Gaussian amplitude probability density.
- Gaussian noise has the amazing property that linearly
- filtering it preserves its Gaussian amplitude density and
- that sums of Gaussian random variables are again Gaussian.
- The two terms shouldn't be confused. It is possible to have
- Gaussian white or pink noise.
-
- 14.0 Recording
- There are more different recording systems available today than
- ever before. Digital and analog are both available to the
- consumer. With the advent of consumer digital recorders, used
- pro analog recorders are becoming available for surprisingly low
- prices. Now may be the time for you to buy a microphone and
- recorder and make your first!
-
- 14.1 What is DAT? What is its status today?
- DAT (Digital Audio Tape) is currently the standard professional
- digital format for 2-track digital recording. DAT had a
- short-lived consumer presence, but never "made it". As digital
- recorders have no tolerance for clipping, using a DAT recorder
- takes a slightly different knack. The results can be worth it,
- however, as DAT format offers the same resolution and dynamic
- range as CDs. DATs record for up to 2 hours on a tape, and can
- run at three different sampling rates: 32 kHz, 44.1 kHz
- (for CD), and 48 kHz (the DAT standard).
-
- 14.2 What is DCC? What is its status today?
- DCC is Philips' attempt to modernize the regular cassette. DCC
- decks can play analog cassettes, and can record new Digital
- Compact Cassettes. They use stationary heads (DATs use rotary
- heads as do VCR's), and although they are digital, they use
- lossy compression to fit all the data on the cassette. Although
- DCC sound quality is far better than the 1960 standard cassette,
- the DCC does not have the sound quality present in DAT or CD.
- DCC may be a good choice for consumers who want to assemble mix
- tapes for cars or walkmans, but is not suitable for any
- professional applications. As of December 1992, DCC is very
- new, DCC equipment is very expensive, and the ultimate future of
- DCC is not assured.
-
- 14.3 What about writable compact discs? What is the status today?
- Recordable CD's are available, but are very expensive. Blank
- discs sell for approximately $35 each, and the recorders start
- at around $6,000. These units are mostly used by recording
- studios and other audio professionals.
-
- 14.4 What is the best cassette deck under $200?
-
- 14.5 What is the best cassette deck under $400?
-
- 14.6 What is PASC? Can I hear the effects?
- PASC (Perceptual Audio Sub-band Coding) is a data-compression
- algorithm. It increases the length of recording that can be
- stored in a given number of data bits by eliminating sounds that
- the developers' research claims can not be perceived by human
- listeners. Its most important component is the omission of
- quiet sounds that occur at the same time and near the frequency
- of louder sounds. It provides up to a 4x increase in the length
- of recordings a given digital medium can hold; this is essential
- to allow full-length digital recordings on DCC (and on MD, which
- uses a different compression technique). It is not necessary
- to translate CD data to analog before compressing it using PASC,
- nor the reverse, but today's DCC decks do not have digital
- inputs or outputs.
-
- You CAN hear PASC, but it is very difficult, since it is not
- a distinctive noise (like a hiss) nor a consistent diminution
- (like a notch in a speaker's response), but a broad,
- uncorrelated dropout in a changing collection of sounds that
- are masked by sounds that you can hear very easily.
-
- Since it is lossy, repeated PASC recording will cause
- progressive loss, and this signal damage may become easily
- noticeable. This is a side effect that recording companies
- hope will have the effect of discouraging piracy via DCC.
-
- 14.7 What is SCMS? Can I hear the effects?
- SCMS (Serial Copy Management System) is a copy-protection system
- intended to stop rampant piracy of commercial recordings to
- digital tape. SCMS allows the home taper to copy from a CD to a
- digital tape, but prevents anyone from digitally copying that
- new digital tape.
-
- You CANNOT hear SCMS.
-
- 14.8 How can I bypass SCMS?
- There are professional devices used by engineers to manipulate
- the digital bitstream, but they cost several hundred dollars and
- are not cost effective for consumers. If you need to make
- perfect digital copies of digital copies, buy a professional
- digital recorder. Pro models do not have SCMS, are more durable
- than consumer recorders, and may have better quality electronics
- than consumer models.
-
- 14.9 What's this about a tax on DAT?
- Every digital audio tape recorder and every blank digital tape
- sold in the USA is priced to include a "premium" or "tax". This
- tax is collected by the US Copyright Office and distributed to
- the recording artists and record companies that own the
- copyrights to commercial music. These fees are supposed to
- repay them for lost royalties.
-
- Many believe that this "tax" is illegal, because it represents
- an assumption that the buyer will use the recorder and tape to
- violate a copyright, and not to record their own works. A
- founding principle of the USA legal system is that everyone is
- assumed innocent until proven guilty.
-
- If you believe that this law is unjust, write your elected
- representatives.
-
- 14.10 Is it legal to copy an LP, CD, or pre-recorded tape?
- In the US today, it may be legal to copy LP's, CD's, etc. for
- your own private use (such as to copy a CD to play on your
- walkman). UK law specifically prohibits this, but it is almost
- never enforced. It is definitely not legal in the US, UK, or
- almost anywhere else, to copy these sources for commercial
- purposes, or to give the copies to others.
-
- It is as of yet unclear whether you own the rights to sell
- or give away a copy of a recording if you made the copy on media
- which was sold with an included digital audio tax.
-
- 14.11 How do I clean and demagnetize tape heads?
- First, a caution: DAT recorder tape heads are VERY fragile.
- Before cleaning the heads on a DAT recorder, get specific
- recommendations from a very knowledgeable source that is
- intimately familiar with DAT head cleaning. In the internet,
- a good source is the DAT-Heads-Digest FAQ. For more information
- on DAT-Heads-Digest, see section 20.2, below.
-
- To clean tape heads, use pure isopropyl alcohol and lint-free
- swabs. Wipe the metal parts of the transport with alcohol
- (DON'T wipe the rollers!) and allow them to dry. Throw the swab
- away after use. Be exceedingly careful when cleaning the heads
- on a DAT. DAT heads are notoriously easy to misalign by
- incorrect cleaning.
-
- Practical tape head demagnetizers are available for under $10.
- Try to find one with a plastic coated tip. If you can't find
- one which is plastic coated. you can slip a drinking straw or
- plastic tube over the tip for the same effect. This plastic
- will prevent the demagnetizer from scratching the head.
-
- Before plugging in the demagnetizer, remove all tapes from your
- working area and unplug the recorder. Hold the demagnetizer
- away from the recorder as you plug it in. Slowly bring the tip
- of the demagnetizer up to the tape head and slide it back and
- forth across each tape head for five one-second strokes. Then
- pull it away from the head slowly and go on to the next. After
- demagnetizing the heads, use the tip on each metal tape guide
- with a similar five strokes. Last, slowly pull the demagnetizer
- far away from the recorder and unplug it. Recording engineers
- use a demagnetizer before each recording session.
-
- 14.12 How do I adjust a tape recorder for best results?
- Adjusting a tape machine for best results usually requires
- special equipment and test tapes. Unless you know what you're
- doing, leave it for a pro. If you are serious about doing it,
- buy the service manual for your particular tape recorder. It
- will list a detailed procedure, as well as describe the correct
- test tape and tools.
-
- As for setting of record levels, it is best to experiment with
- different levels on different tape brands. Different
- formulation will reach saturation for different levels.
- Generally speaking, the transients on a Chrome tape should peak
- at about +6 dB above 0, though some formulations can take
- significantly hotter signals.
-
- 14.13 Where can I get new pinch rollers or drive belts?
- Projector-Recorder Belt Company
- Whitewater WI USA
- 800-558-9572
-
- 14.14 What is a good rubber (pinch) roller cleaner?
- Teac RC-1 available from
- J&R Music World
- 59-50 Queens-Midtown Expressway
- Maspeth NY 11378-9896 USA
- 800-221-8180 or 718-417-3737
- Tascam Rubber Cleaner RC-2 available from:
- Tape Warehouse
- Chamblee GA
- 1-404-458-1679
-
- 14.15 How can I program a recorder to tape a radio broadcast?
- Radio Shack and Panasonic make a clock/radio/cassette that can
- be set to record at a specific time. Radio Shack also sells 120
- minute cassettes, which can be used for 60 minutes per side.
- The recorders are not high quality, and the long tapes are
- fragile, but it works.
-
- You can buy "appliance timers" at hardware stores that will
- start and stop an appliance at a specific time. Radio Shack
- sells fancier versions of the same thing for more money. Gadget
- freaks love "X-10" control systems. These can be configured to
- do the same thing. All require a recorder that can be left in
- RECORD mode. Such recorders are identified by a "TIMER" switch
- on the front panel. Many cassette decks have a TIMER switch for
- use with timers.
-
- Memorex sells a "CP-8 Universal Remote" with a built-in timer.
- Available for approximately $90.00 from either:
- Crutchfield
- 1 Crutchfield Park
- Charlottesville VA 22906 USA
- 800-955-3000 or 804-973-1811
- or
- J&R Music World
- 59-50 Queens-Midtown Expressway
- Maspeth NY 11378-9896 USA
- 800-221-8180 or 718-417-3737
-
- This can be set to start a recorder at a particular time. As
- the recorder will be started from a remote control rather than
- by the power line voltage, no timer switch is required. Radio
- Shack has a very similar product available for $99.95, may be
- less on sale.
-
- Damark also sells a learning remote with a built in on/off
- timer and sleep timer. It can learn 17 commands per device on a
- total of 5 devices and should be great for taping a few shows.
- They also sell a 8 device remote with timer. As Damark sells
- close-outs, these items may not be available in the future.
- Damark
- 7101 Winnetka Avenue North
- PO Box 29900
- Minneapolis MN 55429-0900 USA
- 800-729-9000 or 612-531-0066
-
- There is a similar learning remote available from MCM
- Electronics. They call it a Lonestar Learning Universal
- Remote, item 80-450, $24.95 on sale.
- MCM Electronics (Speakers, A/V Repair Parts, Etc) (+) (C)
- 650 Congress Park Dr
- Centerville Ohio 45459-4072 USA
- 513-434-0031 or 800-543-4330
-
- Use a VCR for audio-only recording. Hook the audio in to the
- output of a radio, tuner, or receiver. You may also have to
- connect some video signal to the VCR so that the sync circuits
- work correctly.
-
- 14.16 Will CrO2 or Metal tapes damage a deck made for normal tape?
- No. They will work fine. They are no more abrasive than common
- tape and may actually be less abrasive than very cheap tapes.
- Recorders which are designed for CrO2 or Metal tape have
- different bias settings and equalization settings to take best
- advantage of the greater headroom and to give flat response with
- these different types of tape. However, they use similar if not
- identical heads as less expensive tape recorders. Almost all
- tapes are in some way lubricated, and these lubricants minimize
- wear and squeaking.
-
- 14.17 Why do my old tapes squeak in my car cassette deck?
- One problem that will cause this is "binder ooze". The binder
- is the glue which holds the oxide particles to the backing.
- With time, this binder can ooze forward and actually get past
- the oxide particles, so that there is sticky stuff on the
- surface of the tape. When this sticky stuff goes past the
- heads, it can cause a slight stick, which will sound like a
- squeak. You won't feel it with your fingers, but it is there.
- If you have a prized tape with this problem, consider baking
- the tape in a home oven at a very low temperature, like 150F.
- This might cure the problem by drying out the binder.
-
- 14.18 Is VHS Hi-Fi sound perfect? Is Beta Hi-Fi sound perfect?
- The HiFi recording format is subject to two different problems:
- Head-switching noise and compression errors.
-
- To get perfect reproduction, the FM subcarrier waveform being
- played back by one audio head must perfectly match the waveform
- from the other head at the point of head switching if a glitch
- is to be avoided. If you record and then play the tape on the
- same VCR under exactly the same conditions, you have a
- reasonable chance of this working. But if the tape stretches
- just a bit, or you play it on another VCR whose heads are not in
- exactly the same position, or the tracking is off, the waveforms
- will no longer match exactly, and you will get a glitch in the
- recovered waveform every time the heads switch. This sounds
- like a 60 Hz buzz in the audio, which is often audible through
- headphones even if not through speakers.
-
- The same glitch will occur in the video waveform too, but since
- head switching always happens during vertical retrace, you won't
- see it.
-
- The wonderful signal to noise ratio of VHS HiFi is achieved
- through the use of compression before recording and expansion
- after playback. The actual signal to noise ratio of the tape
- itself is about 35 dB and a 2.5:1 compressor is used to
- "squeeze" things to fit. Like all companders, this produces
- audible errors at certain places on certain signals, such as
- noise "tails" immediately after the end of particularly loud
- passages.
-
- Worse, compressors often have problems simply getting levels
- right. That is, if you record a series of tones, starting at
- -90 dB and working up in 1 dB increments to 0 dB, and then play
- them back, you will almost invariably have level errors. The
- trend from soft to loud will be there but the steps won't be
- accurate. Two or three of your tones might come out at
- essentially the same level, then the next one takes a big jump
- to catch up or even overshoot.
-
- For music, the result will be that the relative levels of some
- instruments, passages, etc. will not be accurate.
-
- This doesn't matter as much for movies, which tend to have
- steady volume level. Also, movie enjoyment is rarely hurt by
- these level errors. VHS and Beta HiFi is fine for reproduction
- of movie and tv soundtracks. They are also perfectly fine for
- non-critical audio applications. But VHS and Beta HiFi are not
- serious competitors to DAT, CD, open-reel analog tape, or even a
- high quality cassette deck.
-
- 14.19 How do HiFi VCRs compare to cassette recorders? DAT recorders?
- VHS HiFi and Beta HiFi are analog recording formats which use
- modulation techniques to record a video signal and a stereo
- audio signal on a videocassette. The audio capabilities
- typically surpass that of the "linear" audio tracks found on all
- video recorders, thus the "HiFi" designation. "HiFi" is
- essential for getting good sound quality on your video
- recordings and out of pre-recorded videos.
-
- HiFi is also touted as an excellent audio recorder for
- audio-only (no picture) applications. On paper, the
- specifications are typically superior to analog cassette but
- inferior to DAT. In reality, the quality of HiFi video
- recorders is better than low quality cassette recorders but not
- as good as high quality cassette recorders when they are used
- with noise reduction systems. In no case can a HiFi video
- recorder compare to DAT. It suffers from generational loss and
- audible noise.
-
- Many people use VHS HiFi for recording radio broadcasts, since
- VCRs often have built-in timers and can record for up to 9
- hours. If you use a HiFi video recorder to record from an
- audio-only source, beware that some decks will not function
- properly without a video signal for synchronization. If you are
- interested in very good quality sound, use a deck with manual
- level control.
-
- 14.20 What is the difference between VHS HiFi and Beta HiFi?
- VHS HiFi uses "depth modulation"; Beta HiFi uses "frequency
- modulation".
-
- 14.21 Is there any good reason to buy a HiFi VCR for common TV shows?
- If you do not own a stereo TV, the purchase of a HiFi VCR will
- give you the capability to listen to stereo TV broadcasts to
- your system.
-
- 14.22 What is the best cassette tape?
- One simple answer to this question is that the best tape is the
- tape which was used to align your tape recorder. A second
- simple answer is that more expensive tapes are frequently
- better in terms of quality of the backing, durability of the
- oxide, accuracy of the shell and guides, and life.
-
- Background: When you make a tape recorder, you build electronic
- circuits which have specific, non-flat frequency response.
- These circuits correct for the non-flat response of the tape
- heads, the recording process, and the tape. These circuits can
- be adjusted after the recorder is made, but adjustment is
- tricky, and may or may not be successful with every tape made.
- The designer of the tape recorder picked one tape as their
- standard when they did the design, and built that recorder
- to work well with that particular tape. It may work better
- with a different tape, but it won't necessarily sound the
- best with what one person calls the best sounding tape.
-
- From a review of frequently given answers to this question,
- it is obvious that almost every brand of tape has its advocates.
- Many brands also have their detractors. Maxell and TDK tend to
- have a strong following, but that is in part because they own a
- large share of the US tape distribution market.
-
- 14.23 What is the best Reel-to-Reel tape?
- See 14.22. Just as cassette tape recorders are set up
- specifically for one type of tape, reel-to-reel tape recorders
- are equalized and biased so that they are best with one specific
- brand and model of tape. Just as more expensive cassette tapes
- will last longer and have less noise than cheaper ones, you can
- expect fewer dropouts, better quality control, and lower noise
- from more expensive reel-to-reel tapes.
-
- The major brands in reel-to-reel tape include Ampex, Scotch
- (3M), AGFA/BASF, and Maxell.
-
- 14.24 What is Type I, Type II, Type III, and Type IV cassette tape?
-
- 15.0 Mail Order
- Mail order is appealing. The general hope is that by using mail
- order, you avoid pushy sales people, you pay fixed, discounted
- prices, and you have written catalog descriptions to help you
- select your purchase. In practice, most mail order today is
- "phone order", in that the company completes the deal with a
- phone call. Many of the "mail order" companies don't even have
- price lists or catalogs. They are just retailers that are
- willing to sell over the phone and ship the merchandise to
- you. In some cases, retail store sales are better deals than
- mail order. Don't expect the lowest price from the first place
- you call. Also, don't expect excellent service from everyone,
- and especially not from the company with the lowest price.
-
- 15.1 Who sells brand XXX equipment mail-order?
- Consult the frequent rec.audio mail-order survey published by
- nau@SSESCO.com (William R. Nau) or contact William Nau directly.
- This survey is also available via FTP in the pub/rec.audio
- directory of SSESCO.com. If you have any mail order
- experiences to share, please send them directly to William Nau.
-
- 15.2 Is the stuff sold by DAK really awesome? Damark?
- DAK buys in large quantities. They buy what they think
- they can sell. They buy close-outs as well as new first-line
- merchandise. They honestly represent their merchandise with
- specifications. They offer more information on their product,
- if possible, on the phone through their toll free number.
- I know of many people who have bought from DAK and been
- happy. I personally have bought from DAK and been happy.
-
- Regarding Damark, opinions of people on the net are similar.
- The products are as described, they deliver what they
- say they will, and will take back or replace unsatisfactory
- merchandise. I have not heard any unsatisfied Damark customers.
-
- On the other side, the catalog writers at DAK use some very
- flowery language which is intended to lead you to believe
- that they are selling gold for copper prices. In this sense,
- the words in their catalog may be deceptive.
-
- The DAK people have a good sense of "what the market will bear".
- They price their products to sell, but not to give away money.
- Mail order prices tend to be 10% to 20% less than discount,
- which is 10% to 20% less than retail. DAK has to compete with
- other mail order dealers, such as Damark, but they send out SO
- MANY CATALOGS that they really don't have to cut prices too far
- to sell.
-
- DAK has recently gone through hard financial times. This puts
- buyers in some slight risk, because if they go out of business,
- you may get easy warranty service on their products. I say
- easy because most DAK products are covered by a manufacturer's
- warranty, and you can often get service from the manufacturer
- as well as from DAK. I believe that DAK is over their slump,
- but I am not sure. For more on warranties, see 19.1, below.
-
- 15.3 Is the stuff sold by Cambridge Sound Works really awesome?
-
- 15.4 What should I watch out for when buying mail order?
- Many of the cautions mentioned in warranties (19.1) apply.
- Look for a store which has been around a long time. Look for
- friends which have dealt with the store and been satisfied.
- Look for a store which does not lie or stretch the truth.
-
- 15.5 What is gray market?
- See warranties (19.1), below.
-
- 15.6 Are there any good mail-order sources for recordings?
- Noteworthy has a good reputation among net readers as a supplier
- of CDs. They have a range of discs available centered firmly on
- the mainstream, and are reasonable in price. Shipping is $3.75
- for 1-5 CDs. They offer over 14,000 different CD titles. Their
- offerings are all from US labels. They give a free catalog and
- also have modem software and catalog on floppy discs for $9.95.
- Noteworthy Music, Inc
- 17 Airport Road
- Nashua NH 03063 USA
- 800-648-7972 Voice
- 603-881-5729 Voice
- 603-883-9220 FAX
-
- BMG and Columbia also sell CDs mail-order, but have a smaller
- list of offerings and higher prices. However, BMG and Columbia
- have interesting deals to entice new customers. Read the fine
- print before you sign to be sure that they are right for you.
- BMG and Columbia both have promotional offerings to "members"
- which allow you to buy two or three discs for the price
- of one. These can be very good deals, if you want what they
- have. Look at their advertisements in common magazines and
- Sunday newspapers for a better idea of what they carry. They
- list much of their line in their ad. Don't expect much more.
-
- Bose Express also sells CDs. Their reputation so far is very
- knowledgeable people, a large collection, and high prices.
- Their catalog costs $6.00.
- Bose Express Music
- The Mountain
- Framingham MA 01701 USA
- 800-451-2673 or 508-879-1916 Ext. 2008
-
- Tower Records has a mail order department which also sells CDs.
- Their classical catalog costs $13.45. Their other catalog costs
- $10.45. Tower is a large retail chain. Many have bought from
- their retail outlets happily, but no one has expressed any
- comments on their mail order service yet. Contact:
- Tower Records Mail Order Department
- 692 Broadway
- New York City, NY 10012 USA
- 800-648-4844 or 800-522-5445
-
- Another source is Music New Hampshire; 800-234-8458. They sell
- many $3.79 post-paid sampler CDs and also many independent label
- single-artist discs. Most single artist discs are $15.00 each.
- Shipping is $3 for 1-3 discs and $5 for 4-up. Their stuff is
- mostly obscure artists. They have Rock, Jazz, Classical, Folk,
- Country, and Children's offerings. Affiliated with CD Review.
- Music New Hampshire - Wayne Green Inc
- 70 Route 202N
- Peterborough NH 03458-1107 USA
-
- If you like the idea of buying CDs by Modem, consider
- The Compact Disc Connection
- 1016 East El Camino #322
- Sunnyvale CA 94087 USA
- Voice 408-733-0801
- Modem 212-532-4045 New York City NY
- 312-477-3518 Chicago IL
- 408-730-9015 Sunnyvale CA
- 617-639-0238 Boston MA
- They have a collection of over 58,000 CD titles. People have
- said that their service is excellent. Prices are fairly good.
- Shipping is $3.50 for orders under $100.00 and free for larger
- orders. They do not stock anything, but deliver from the
- warehouses of their suppliers. This means that some items may
- be back ordered or completely discontinued while remaining in
- their on-line data base. They advertise 94.2% of orders in
- 1992 shipped, though not necessarily immediately. If you have
- a modem and enjoy browsing a data base, their data base is a
- a very enjoyable experience. However, the phone bill can be
- quite prohibitive to those calling from out-of-town.
-
- There have been a couple of music (cd/lp) mail-order lists
- compiled on the net - one older list can be found via anonymous
- ftp to ftp.uwp.edu in the file: /pub/music/misc.mailorder.rmm
- Someone is revising this file and it should be updated or found
- in a new file name there in the future.
-
- Another list contains vendors that specialize in progressive
- rock, electronic and experimental music, is maintained by
- Malcolm Humes and posted sporadically to alt.music.progressive,
- rec.music.misc, & rec.music.info. This also can be ftp'd from
- ft.uwp.edu, in the file: /pub/music/misc/mailorder.progressive
-
- Federal Music and Video markets "Discount Coupon Books"
- featuring two-for-one CDs and Tape deals. They require payment
- with the order, which many consider risky. One company that
- distributes these coupon books for Federal Music is Reed Music.
- The price from Federal or Reed Music with the two-for-one deal
- is comparable to the price from Noteworthy. So far, no net
- user has yet related any positive or negative experience with
- Reed Music or Federal Music and Video. Federal Music and Video
- has been in business since 1985, so is probably legit. However,
- in that they require payment in advance it is probably safer to
- avoid them completely and use a discounter like Noteworthy.
-
- When considering mail purchases of CDs, consider shipping costs.
- It is common for people to charge between $1 and $3 per disk for
- "shipping and handling". This makes mail order less attractive,
- but may be equally balanced by a lack of sales tax.
-