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Subject: FAQ: rec.audio (part 3 of 4) Newsgroups: rec.audio,rec.music.info,rec.answers,news.answers From: Bob Neidorff <neidorff@uicc.com> Date: Mon, 14 Mar 1994 20:04:19 GMT 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.