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Understanding Home Stereo Basic Information for Stereo Shoppers A good hi-fi used to be high on the list of people's purchasing priorities. For many people it still is, but for a great many others it ranks down the list somewhere between a microwave oven and a couch. Many people confuse mass market rack systems or discount store stereos with real hi-fi. A real hi-fi system brings the benefits of the world of music into your life like nothing else can. A good system will help you relax, stimulate your imagination, and help educate your children. People with really good systems listen to them all the time. They also attend more live musical performances and enjoy a wider variety of music. Our goal is to make music more fun for you to listen to at home - to make music a more important part of your life. A great many people think that they "don't have good enough ears" or "won't be able to hear the difference". Unfortunately, this is caused by stores that sell mass market disposable stereos and magazines like Consumer Reports. They propagate the idea that everything sounds the same - or try to confuse you with technical talk. The really great news about hi-fi is that everyone can tell the differences - if it is better, then it sounds better. If it doesn't sound better, then it simply isn't better. It really is that easy. You will be able to hear the differences. There are four basic rules to building or improving a hi-fi system. These rules are always the same, regardless of the size or price of the system. This is the key to understanding how to create a successful system from the hundreds of components available: 1. The Equal Importance Of All Parts - The Balanced Approach In a music system, the recorded information is retrieved from the software (records, compact discs, and tape), converted to an electrical signal, and sent to the electronics. The electronics produce a larger copy of that signal, and then send it to the speakers. The speakers convert the signal into the sound that you hear. Information is passed down a chain, from one component to the next, and in only this direction. The most important fundamental is that nothing in the chain can improve upon what is sent to it. And, like a chain, all the "links" are equally important. Contrary to popular belief, the speakers are of equal importance - not more or less important than any other part of the system. The source is the compact disc player, or turntable (or the tuner, or tape deck). This is where the information is put into the system. This is often the weak link in a stereo system - but really shouldn't be. From the beginning of the system to the end, nothing can improve the original signal. The very best equipment simply does not degrade the original signal as much as lesser equipment does. Simply put, music reproduction is a damage control job. Because we can't make the sound better than it is on the disc, the goal is to degrade it as little as possible. If information is lost or damaged (distorted, changed, altered) at the source, nothing else down the chain can make up for, or repair it. You simply must put something good into the system to get something good out. From the source, the information is sent to the electronics. This is the amplification section of the system, known as the preamp and the power amp (or combined in one box with a radio: the receiver). The preamp is the control center - the heart of the system. Of the two pieces, the preamp is unquestionably more important. The amp makes a larger copy of what is sent to it from the preamp, so to a very large degree the preamp determines how the amp will sound. The amplifier has two tasks: first to increase the small electrical signal (it receives from the source) to a larger signal that will power the speakers. Second, the amplifier must control the speakers. For example, bass reproduction is as much an amps job as it is the speaker’s job. From the electronics, the signal is sent to the speakers. The speakers turn the electrical signals into vibrations - sound. A good speaker will only reproduce what is sent to it, not add or subtract anything. If the speaker adds anything (bass, boxiness, sizzle, etc.) it is altering or distorting the sound. Therefore, a good speaker should make a poor recording sound poor or a cheap cd player sound cheap. Very often people blame the speakers for a poor sound when the speaker is only faithfully reproducing the poor signal sent to it. (More on this in the Understanding Speakers section.) A balanced approach will always give you the best sound for the money. This is just as true when you are upgrading or improving your system as when you are purchasing a completely new system.
While we like to refer to various components as improving the sound of a system, the more realistic perspective is to realize that there are really no "good" components, there are only those that are "less bad". We can not make the sound better than the recording. Whatever is on the software (the CD, laser disc, tape, record, etc) is all we have to work with. Ideally we would get all the information off of the software, through the system, and out of the speakers without changing it at all. Since nothing in a stereo system is perfect, that isn't possible. Our goal, therefore, is to minimize the change. Imagine looking through four pieces of glass. The more pieces you clean, the clearer the view. Remember, you don't have to clean all of the pieces at the same time to see an improvement! It's the same when it comes to improving your stereo system. Contrary to popular belief, a good hi-fi system is one that is simple. We want to use the fewest number of the best quality pieces we can afford to accomplish the task. The better the equipment the simpler it tends to be, with fewer controls, knobs and switches. Remember, we are trying to minimize change. (The basic problem with equalizers, expanders, etc. is that they change the sound and therefore make it worse.) Since even the best equipment alters the sound to some extent, we want to keep this to a minimum. At the same time, the simpler the equipment, the easier it is to use. And the easier it is to use, the more it gets used.
When we buy a car, we don't buy a Corvette body, Porsche brakes, Cadillac interior, Jaguar chassis, Volvo engine, and all season tires. We buy a complete car; one that is a balanced blend of specific parts that work together as a whole. Likewise, a hi-fi music system must be viewed as a whole system. All too often "good" pieces are combined to make a poor system. Amplifiers are incorrectly matched to speakers, cheap turntables are fitted with expensive cartridges, cheap CD players are hooked up to good electronics, half of the budgeted funds are spent on speakers, or good equipment is hooked together with poor cables. All these mistakes are very common. The result of these mistakes is that when the components are connected, they do produce sound. Making sound, and reproducing music, however, is not the same thing. When a system is improperly designed and assembled, the reality is that the money spent did not result in a good value or an enjoyable music reproduction system. It just isn't that much fun to listen to! Better results could have been achieved with components that complement each other. And it wouldn't cost any more.
The only reason to purchase a home music system is for enjoyment. As obvious as this seems, this is often forgotten by salespeople and customers alike. It is important to look at the options available and make a decision as to what is required to make this system fun for you. The main goal of this paper is to help you understand how to put together a music system that will reproduce music as faithfully to the original performance as possible. Most people will choose the better sounding equipment when they are shown the difference. But, you must hear it for yourself. For many people, however, the sound quality is not the only important requirement, and we understand that. Perhaps it is important to you to be able to operate the complete system with remote controls. Perhaps your main concern is to tie the music system into your video system, so that you have "movie theater sound" when you watch movies at home. Perhaps the most important thing to you is to have music in every room in your home and at pool side. Your goal then is to get the best sound you can, given your other requirements. After listening to the options, you need to decide what is important to you, but make an informed decision. Most people will give up a remote for better sound when shown the difference. You need to listen to both options to make that decision. The more specific you are in letting us know what you want and what isn't important to you - the better we will be in directing you toward the right gear. Remember, above all else you are buying the system for your musical enjoyment.
Listening to equipment in an environment similar to your home and with one set of speakers at a time will make the differences in equipment more obvious, and more relevant to your needs. The difficulty comes if you have made up your mind before listening (i.e. "I want a speaker with a 15 inch woofer") and the listening contradicts your fore drawn conclusions. Try to keep an open mind and trust your ears. Here are some guide lines that will always hold true, for all equipment. Sit down, relax, and listen to the music. Ask yourself musical questions: Do the musicians seem to be playing together? Are they playing well or poorly? Can you hear all of the instruments? Can you pick out the bass line, or any other part and follow it easily? Can you follow the melody easily? Do the voices seem natural? Are you responding to the music, for example tapping your feet? If it is familiar music, is it more fun to listen to than the last time you heard it? Does the music seem choppy or does it flow smoothly? Does anything seem excessive? Can you visualize the locations of the musicians and instruments in front of you? You will soon discover, as everyone does, that you don't have to be an expert to tell the difference. Also, get out and listen to some live music. Live music has a quality all its own. Listening to live music will help you judge the quality of reproduced music. But how will the equipment sound in your home? We allow you to borrow a piece of equipment to confirm the results in your system. We ask that you do the comparisons at home - not in another store. Most stores won't let you try equipment at home. The results of a head to head comparison don't benefit them. We do it all of the time - just set up a time in advance so we know the equipment will be available. One last point: the system must be set up and adjusted properly to perform as it was designed to. The positioning of the speakers, the speaker stands, the equipment stand or cabinet, and especially the interconnecting cables and
The part of the system that we refer to as "the electronics" is the amplification. This can be the receiver, the integrated amp, or the pre-amp and power amp. It is the most complex and often the most expensive part of the system, but it is also the part most people expect everything to sound the same. In the early days of audio, electronics were available only in kit form. Stereo equipment companies emerged and soon there was a variety of equipment. The early electronics were, relatively speaking, better than the early speakers. That led to two misconceptions: the first was that the speakers were more important than the electronics. The second was all electronics were pretty much alike. That, combined with the fact that speakers are easier to "understand" and therefore easier to sell, enhanced the misconception. Still, some equipment became recognized for its superiority, the most notable were McIntosh and Marantz. From the 1950's into the 60's, these two companies built the best electronics available. With the Japanese entrance into the stereo business in the 60's the great differences in electronics had begun. The receiver was born. The quest for cheaper was on. The older tube equipment, while measuring worse than the new solid state (transistor) equipment, sounded better. The older tube amps were limited in their abilities to reproduce extended high or low frequencies, but had a warm smooth mid range. The new transistor amps were using transistors in circuits generally designed for tubes, and with bad results. They had extended high and low frequency response, but were very harsh and irritating to listen to. Gradually, things improved and solid state replaced tube equipment as the norm. Driven by the marketing departments of the large Japanese companies, technical specs replaced listening as a means of judging the quality of equipment for most people. Pioneer, Sansui, and JVC are names you'll remember. The "distortion- wars" were on ... but while numbers got better, the sound generally got worse. Slowly, a few small companies emerged and began building equipment utilizing newer, high quality parts and new circuit designs. This time however, the goal was sound quality and not distortion figures. During the 1960’s McIntosh and Marantz were the best companies in electronics. However, in the 70's and 80's they were greatly surpassed in terms of sound quality and construction by companies like Mark Levinson and Audio Research. Hi-End (or high performance) audio was born. (Note: McIntosh is now owned by the Japanese car stereo manufacturer Clarion and Marantz is owned by Philips).
The single greatest reason that separates are better than receivers is there are less compromises. The greatest compromise in a receiver is the use of a single power supply for all three sections (the pre amp, power amp and tuner). The needs of the power amp section affect the preamp section. The result is receivers are not as smooth, effortless, open and full sounding as separates. (Integrated amps are generally better than receivers, but in most cases still not as good as separates.) As we said earlier, the preamp is more important than the power amp. Some people have asked about using a cd player directly into an amp, or passive preamps (basically the same thing). We have evaluated quite a few passive preamps and have found them all to rob the music of its dynamics and drive. In other words, you get less bass and the sound is flat and lifeless. Any system without a preamp can be made to sound much better by installing one. The biggest surprise is the vast difference in separates. This is due to different circuit designs, higher quality parts (transformers, resistors, capacitors, volume pots, wire, connectors, etc.) and sturdier or more precise construction. The differences in high end equipment are as obvious as the differences in mid priced equipment. All expensive speakers or amps are not of equal quality. Some are built to exacting standards, while others are put together by a couple of guys in a garage. Again, the difference is easiest to understand simply by listening. Therein is the whole reason for high end audio: if it really is better, it will sound better! And if it sounds better, it will make listening to music more fun! Better parts and assembly techniques will insure consistency from piece to piece and over time. In the long run, the best equipment proves to be the best overall value too. *An interesting note is that the very best electronics have always been American made.
As stated earlier, to improve your stereo system we look for the weakest link in the chain. If, however, you are looking to improve your video enjoyment, a good surround system is essential. A good surround sound system can enhance the impact of a home video presentation more than a large screen TV, and the combination of the two will provide as much excitement from a movie as is possible to experience at home. The correct set up and positioning of the speakers in a surround system is absolutely critical. It is especially important for dialog to remain at the screen while the sound effects are isolated from the screen. The only way this can be done is with logic steering (Dolby Pro Logic, Dolby Digital, DTS, etc.) along with proper amplification and appropriate speakers. This brings us to the reason that surround sound usually makes stereo systems sound worse. Simply, most people break all of the rules of hi-fi to get surround sound. They use a poor quality surround receiver, five cheap speakers that are not placed properly, and/or they don't properly adjust the system. Remember, if you are replacing a regular two channel stereo receiver with a five channel surround receiver, you must spend more money (25-30% more) to get the same quality of sound. A receiver is already the most compromised piece of audio equipment made. The single power supply limits its performance. When additional channels of amplification and a surround processor are added - all getting their power from the one power supply - we end up with a piece of equipment that often tries to mask poor sound with sound effects. It may work okay for movie sound effects, but it can really wreck music. Remember, movie sound is mostly music and voice. Always use music to evaluate surround sound systems. If you are looking to improve a music system (a system you will not be using for video sound) then surround sound is not the way to improve it. If you want to get the most enjoyment out of movies, however, you can't beat surround sound. Like everything else in audio, it is quality and execution that make or break surround systems. (For more information on Home Theater and Surround Systems, we have an "Understanding" paper on the subject.)
The enjoyment of music is a personal, subjective experience. What one person considers "good music" may be regarded poorly by someone else. However, this subjective musical preference should not be confused with the objective task of music reproduction - to reproduce the original music exactly as it was performed. This is why there are no "jazz speakers" or "rock speakers" or "classical speakers" - just poor, good, better, and great speakers. Of the 400 brands of speakers available, there are only 15 or so really good speaker manufacturers! There are literally hundreds of poor speakers on the market. As different as good speakers can sound there are two things that all good speakers have in common. One is a seamless sound from the very low bass to the very highest highs (you don't hear the individual drivers). The other is the ability to reproduce voices well. All good speakers do those two things. But let's look a bit deeper. In order to provide a complete and faithful musical experience and to avoid imposing its own sonic character, a speaker should preserve all of several independent musical characteristics: tonal balance, imaging, clarity, dynamic range and bass response. Correct tonal balance ensures that the musical spectrum - from the highs to the lows - is reproduced without over or under emphasis of any part by the speakers own colorations. The ability of a speaker system to recreate the positions and "feel" of the instruments in three dimensional space is called imaging. First, a speaker should not reveal its presence by generating its own false spatial clues because of diffraction or other sources of delayed energy from the enclosure. If designed correctly, a speaker does not sound boxy or tubby, it sounds open and spacious. A speaker that images well will have a good sense of front to back depth and side to side placement of voices and instruments. The sound stage will be wide, extending even beyond the speakers - and the sound that comes from the area in between the speakers remains stable in space and does not shift with changes in listener position. Dynamic range is the difference between the softest and loudest sounds that can be reproduced without significant distortion. Wide dynamic range insures the preservation of contrasts that are critical to musical enjoyment. Sometimes speakers that simply play loud are sold as being dynamic, but a speaker with good dynamic range will preserve the soft to loud contrasts even at lower volumes. A speaker that has good bass response will be able to properly reproduce the very low frequencies in music. The powerful low frequencies provide a musical foundation that greatly contributes to the realism and emotional impact of the music. The bass should be solid, full and clean sounding. Many speakers exhibit a muddy, tubby, mushy, boomy bass that seems to come from a box or cave. You should be able to follow the bass line in a song - as the bass player goes up and down the scale. In other words, all bass frequencies should not sound like the same note. In good lower priced speakers, the lowest frequencies are sacrificed so that the other musical characteristics can be achieved. A lot of people ask about subwoofers. Real subwoofers are speakers that supplement the main speakers and only play the lowest frequencies (the lowest two octaves below 80 hz). Good subwoofers don't play that muddy one-note-bass. They are clean and clear and you can easily follow the bass line in the music. The best subwoofers are a lot of fun and will significantly improve any system. The bass speaker in a three piece set is not really a sub, it's simply a woofer. A lot of wrong information is given out about subwoofers, such as: bass isn't directional, you only need one subwoofer, or you can put it anywhere. Let's set the record strait: bass is directional in a room - the room causes it to be directional. So, placement is important so that the bass blends with the rest of the music. Put the woofer in the back of the room and you'll get a boomy sound from the back of the room. To integrate subwoofers properly into a system you must 1) place the woofer at the same end of the room as the main speakers. To make the bass less directional and blend better you need to cross it over (or transition to the woofer) at a low frequency and ideally use a pair of sub woofers. (Only the very lowest frequencies are not directional). 2) Use proper amplification on the sub woofers (they require great amounts of current from the amps) or use woofers with built in amplifiers and crossovers (a much easier approach). 3) Like everything else in audio, quality is more important than quantity. Choose the clearer sub over the bigger subwoofers (good subwoofers start at about $600- $800). If these rules are followed, the addition of a subwoofer(s) will add greatly to the enjoyment of your system. If these rules are broken, you'll spend good money and make your system sound worse. That's no fun at all.
Another often quoted spec for speakers is sensitivity (sometimes referred to as efficiency). A speaker with higher sensitivity will play louder for a given amount of amplifier power input. This was important in the early days of hi-fi, when a 20 watt per channel amp was considered large - but today it is all but irrelevant. The better speaker designers will sacrifice some sensitivity for greater clarity, bass response etc. In fact, you will soon find that almost none of the great speakers have sensitivity much above 90db. Most good speakers will have sensitivity measurements between 87db and 93db.
One of the most asked questions in audio is "'how many watts is that speaker?" The person is usually asking two questions: "How much power do I need for this speaker?" and "Can I damage this speaker with my amp?" The answer to both those questions is that a speaker is almost never damaged by a large amplifier... it is almost always a small amp that is turned up too far that damages the speakers. When an amp is turned up too far, it cannot reproduce the louder parts of the music over the loud average level. The loud peaks are "clipped" off. This clipping is what overheats and damages the speakers. You are better off with larger and better made amps. Some speakers have fuses or circuits that will give a little extra protection, but the best way to keep from damaging speakers is to buy appropriate electronics, and if you turn the volume up and the sound gets harsh ... turn it down a bit!
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