Saturday, June 21, 2008

22 Tips to Obtain Better Sound

by Steve Oksuz, NoName HiFi

One accepted tenet in the audiophile world is that it almost impossible to achieve the best sound by simply combining the best equipment. A much cheaper but properly selected and tweaked system may sound better than its expensive counterpart. This is called system synergy in audiophile world. System synergy is not only about combining the best equipment, but it is a kind of long and enjoyable way to maximize its performance.

The precautions and principles may seem absurd and meaningless for someone who does not have solid understanding what hi-end is.

Within the last twenty years, I spent considerable time, money, and effort to achieve the best sound (whatever the “best” is). I wrote a couple of important points from my own perspective. Many audiophiles may already know most of these points. More importantly, the below points in this article consist of my own observations. There are so many different tweaks and techniques. I avoided including here the points that I did not try and/or the points that did not work for me. I believe below-mentioned points will improve someone's system to a higher level without having to make radical equipment changes.

The only certain truth I learned after twenty years is that "there is not one absolute truth in Hi-End." Most of the truths in Hi-End cannot be proven by scientific measures. The human ear hears a lot, interprets, evaluates, and decides. In a listening session with three audiophiles, one will find the bass insufficient, the other may find it excessive, and the system owner will think it is perfect. That phenomenon is called "brain reference." Brain reference is a kind of prejudice that comes out of our own system's timbre and tonality. This phenomenon sometimes causes conflicts with someone who compares better equipment versus their own and may not like the sound of the former in spite of its clear superiority.

Most of the points stipulated below will depend on the capabilities of the system, but more importantly, they will depend on the experience of audiophile. A poor system will not differentiate the points, and less experienced ears may not “hear” them either. That's why some of the points below may not be relevant to everyone. I would be delighted if someone who reads this article picks up just one or two points.

1. Listening at Night - Critical listening or equipment testing should be done in the night hours. This rule applies especially to one who lives in a big city. City noise affects our hearing, and we are basically not able to hear what our system delivers to us during the day.

City noise is several times lower in the night, so hidden aspects in the hi-end come out at night and the system delivers its full potential.

2. Heat and Humidity - Humidity and heat have serious influences on sound. Systems cannot generate their best sound, power, and dynamics in warm and damp weather. There may be two reasons: Damp air is heavier, thus the loudspeakers are not able to pull enough air into the room. Or the loudspeaker materials may soften and behave differently in warm weather. Cooling the environment before the listening session eliminates this effect.

3. Darkness - People should listen to music in a dark room. The loudspeakers and the system should be kept in the dark, and the original recording venue should be imagined while listening.

The main objective of a good quality hi-end system is to depart from the hardware and go into the recording environment. Listening to music while watching the hardware will spoil the virtual environment that we want to experience. The most inconvenient part of a hi-end system is the inexistence of visual imaging. The reality sense is different when participating at a live concert or watching a DVD player via a surround system.

If the listening environment is not dark, the listener will perceive the speakers as the sources of the original sound.

4. Find the Correct Listening Distance - Sound is spread in waves called frequency. The volume of every frequency is different depending on the distance from the speakers. In terms of volume, frequencies will be up and down when the distance is changed. Higher mids and treble sections will vary between 20-25 centimeters. The human ear can easily recognize these frequency peaks.

a – To find the correct listening distance, put in a test CD that contains different test frequencies. Start with mono 1000 Hz at the listening chair. Then stand up and walk very slowly around the room (preferably with your eyes closed). You will realize that the signal will have ups and downs in volume while you are moving as if somebody was turning on and off the volume control.

b - The main frequency of the music and the one which is closest to human sound is 1000 Hz. 1000 Hz is your starting point, and you should find the closest distance to your current listening chair where the 1000 Hz is at peak. The ups and downs in that band should be changed around 50-70 centimeters. This is the best location to hear the middle frequencies, but it is not the best location yet to achieve the best frequency spectrum. It is just the starting point.

c - Stick a rope to a back wall and pull that to your shoulders. Now close your eyes and listen at different frequencies such as 300, 500, 1000, 2000, 5000, and 10,000 Hz, etc., while moving the top of your body (while sitting) back and forth. Mark the peak points of every frequency you listened on the rope. Our aim is to find a particular point that most of the frequencies are at their peaks. If you are not successful and these points are not close enough to each other, move your speakers (or your listening chair) 10 centimeters forward and repeat the same exercises till you find a certain point where most of the frequencies are at their peaks.

It is not an easy task. It is time consuming but free of charge. Once you have the point, you will be surprised with the improvement of the sound of your existing system.

5. Room Acoustics - Room Acoustics is the most known but the least considered part of Hi-End. A conventional speaker may throw 40 percent of the sound directly to the listener; the rest of the sound comes through the walls by reflections. Reflection means the timing difference of the original signal, hence it is an additional acoustic which does not exist in the original record. Within such a complexity of reflections, a part of the original signal will come late due to the front wall or ceiling, or a part of the original signal from the left speaker will sound as if coming from the right speaker (or vice versa). Such a complex listening environment will demolish the stereo imaging and channel separation.

Some audiophiles are happy with this case because the speakers seem to have disappeared and the soundstage is wider and deeper. Some producers even add additional mid/treble units to the back side of the speakers (dipoles) to emphasize such effects.

But one thing should be considered - these reflections do not exist at the original sound. If something is produced by the system/room in addition to the original sound, it should be named coloration.

If the aim of a good hi-end system is to reproduce the original sound, such reflections should be avoided as much as possible. Ribbon and electrostatic speakers especially will suffer a lot from such reflections.

Carpet on the floor is a must to lower the reflections (standing waves) between the floor and the ceiling. Thicker curtains will help to lower the reflections of the windows. Glass-covered photos and stiff furniture should be avoided.

This article is not intended to give recommendations on how to soundproof your room. Information on this topic is already prominent on the Internet. The purpose of this section is to emphasize the importance of room acoustics.

6. Precise Focus and Loudspeaker Placement - This is also another known but often ignored part of Hi-End. It is critically important to locate both speakers at the exact same distance to achieve precise focus. Distances should be carefully measured, and both of the speakers should be placed at exactly the same distance from listener.

Why is this step so important?

Sound signals are distributed in waves, as explained in section five. The people who tried the settings in section five will realize that the peaks of frequencies vary in conjunction with the distance from the speakers. Especially the treble frequencies will vary a lot with only one centimeter of a change. In such cases, if one speaker is just one cm closer to the listener, some frequencies will be heard from one speaker but not from the other. If the upper harmonics of the human sound consist of such upper frequencies (they do!), then the sound will move from the middle to left or to right. Moreover, within that case, some frequencies will collide in full phase and will be exaggerated with others will collide in inverted phase and thus are destroyed.

This effect is exactly the same as losing bass when connecting one speaker out of phase.

7. Mechanical Vibration of Electronic Units - Several products exists that absorb vibrations (feet, platforms, etc.). They are to be placed under the electronics/speakers. Such materials have two intentions:

a- To eliminate the external vibration coming through the unit

b- To eliminate the vibration of the unit itself (CD driver motor, speaker cone vibrations)

Most-popular solutions are the cones (spikes). I believe the proper usage of spikes is not known very well. Rather than being a vibration absorber, a spike is a kind of transmission material that transmits vibration from one point to another point. Vibration is condensed to one point and mechanically carried to another platform by the spike but not eliminated. If the connection surface is stiff (e.g., marble or granite), such vibrations are passed to that surface. The area underneath this stiff platform (marble, MDF, glass, granite) must be covered by an elastic material such as cork, mouse pad, neoprene rubber, or similar.

The vibration cannot pass from a stiff platform to an elastic platform and will be transposed to heat.

The direction of the cone is also critically important. The direction should be in conjunction with the intention of the vibration transmission.

The last point about the cone is the cone should be in touch with the chassis of the component directly. If any kind of rubber, double-sided band, blue tack, or other such elastic material is put between cone and the unit, that material will try to transpose the vibration, and the cone will not work.

8. Marble under the Loudspeakers - A marble platform under the speakers eliminates most of the unwanted resonances of the speaker. The thickness of the marble should be at least three centimeters, and the size should be at least 10 centimeters bigger then the edges. The area underneath the marble has to be covered by an elastic material such as cork, mouse pad, or neoprene.

With this arrangement, you have more powerful but clearer and tighter bass, with relaxation at the mid and top frequencies.

The speaker has to be connected to the platform via a cone, not by elastic feet. The sharp end of the cone has to direct to the marble but not to the loudspeaker.

9. Grounding the Metals for Static Electricity - Static electricity can be an issue, especially in wet weather and in fully carpeted listening environments. The carpet is charged with static electricity, which can be passed through the electronic equipment via the rack and/or human touch. Static electricity on the carpet is so powerful that if one checks the carpet in the morning, before anyone walks on it, one can see the static electricity through simple tools sold at RadioShack.

In order to eliminate the effect, the loudspeaker stands and the equipment racks should be connected to earth by a thin wire. Moreover, the loudspeaker cables and interconnects should be lifted away from the floor due to the same effect.

Through this tweak, one will benefit with less-blurry and lower bass.

10. Loudspeaker Distance from the Front Wall - Loudspeaker manufacturers generally recommend the correct distance of the speaker from the front wall (the wall behind the speakers). Generally speaking, the speaker should be located as far as possible from the front wall (and side walls as well). If they are too close to the wall, bass standing waves will be reinforced, and the excessive bass energy will compress the mid/treble band.

Some audiophiles find the desired bass volume by placing speakers closer to the front wall, which is not correct. One thing should be considered – that such bass increase is not due to the original sound, but it is a consequence of the room response, called coloration.

11. Auto former / Transformer Passive Line Stages - New technologies in the hi-end industry could make pre-amplifiers obsolete – at least make their purpose questionable. The purpose of a preamplifier is stipulated in four basics tenets:

a- To connect more then one unit together

b- To record to tape from some sources

c- To provide low volume output and inverted polarity signal of turntables (as the only source component)

d- To fulfill bass and treble adjustment requirements

Nowadays, CD and SACD units can provide 5-8 Volts of output, which is more than enough for the power amplifiers. Audiophiles are not interested in tone adjustments but focused on simplicity. Dedicated phono stages are in common usage; hence, the majority of the requirements are not valid anymore.

The main and the only basic job of a modern pre-amplifier is to lower the volume level, not step it up!

Just try to imagine a pure signal from a CD or DAC through the power amplifier, then cut this link, add four plugs, four female plugs, a pair of interconnects, and lots of resistors, capacitors, tubes, transistors, and all that stuff. How can you keep the signal purity?

An active line stage demolishes the neutrality and the purity of the original sound. Such a corruption may not be so evident in most of the lower resolution systems – or some people may disregard this issue. Every active line stage has its own tonality and coloration. As a matter of fact, audiophiles generally use line stages to balance their tonality problems in systems. For instance, a tube line stage is used to calm down a firm-sounding solid-state power amplifier, or a treble-rich line stage is used to compensate the treble-poor power amplifier and vice versa. If this is the case in a system, the audiophile is not worried about achieving a fully natural line stage or lack of coloration.

For me, the consideration should be to change the power amplifier until one finds the desired sound, rather then playing with a pre-amplifier. In other words, you should deal directly with the original problem rather then trying to mask it.

It is almost unanimous that using a simple volume pot adds neutrality and purity to the sound. But in such cases, other problems appear. A volume pot, which is either a potentiometer or a stepped alternator, works with the resistance principals. Every volume step adds a different resistive path to the signal, thus lowers the volume. Due to the complexity of the music signal (20 Hz – 20 kHz), such a resistive load will act like a barrier for different frequencies. For instance, when turning down the volume level, the treble is lowered, and the bass is condensed – or when you increase the volume, the mids are excessive or vice versa. There can be a lack of dynamic range as well. A line stage eliminates these problems.

Due to these facts, volume control pots or analogue volume-controlled CDs cannot be used stand-alone as line stages. New auto former and transformer passive line stages are developed for volume control. Such units do not work with resistance principals and do not add resistance to the signal path. The only resistance of such amps is approximately 200 Ohms due to the cable in windings.

Transformer passive line stages consist of two transformers, one for the left channel and one for the right. They have one primary winding and multiple (12-24 steps) secondary windings. Their principal is to lower the volume by changing the volts, rather than adding resistance. So far as I know, there are only three producers of such line stages, and I have used two of them. Both of them are providing extraordinary natural, calm, and undistorted sounds.

I heavily modified the Antique Sound Lab myself, which is a very good product and quite inexpensive too (but don't underestimate its price), but Audio Consulting's Silver Rock, made of pure silver, is something else.

It should be also mentioned that such passive line stages are not be suitable for every system. In such a case, input impedance of the power amp should be driven directly by the output stage of the DAC or CD player. Input impedance of the power amp should be as small as possible. The best way to learn this case is to send the impedance values to the producer and request assistance prior to purchasing.

12. Good Tubes (NOS Tubes) - Is it logical to pay 100 € for an old tube when a new one costs 10 €? I believe it is. A good tube can change the characteristics of a tube electronic as if you replaced the entire unit. NOS tubes are not easy to find and quite expensive, but they are worthwhile to use – especially the upper frequency hiss is quite lower with NOS tubes.

13. Very Easy Polarity Finding Method - Generally speaking, European (German) standard AC plugs do not have the signal direction. U.S., U.K., and Swiss AC plugs have one way to connect to AC. So in some cases, it is not easy to find out the correct polarity.

Electronic components, including our televisions, refrigerators, bulbs, and computers, can work properly regardless of the polarity. Why is the AC polarity so important in Hi-Fi?

Electricity arrives from (+), passes the electronic circuit, and departs from (-). Generally the main current arrives in the power supply of the unit first then is reduced to the desired voltage by the electronic circuits. In this case, the power supply section automatically filters the mains. The transformer of the power supply section behaves like an isolation transformer - input and output currents are physically separated. If the polarity is not correct, the mains will arrive to the system directly from the back door and will carry all the pollution, like RFI/EMI, into the unit. So it is important to find out the correct polarity.

Most of a unit’s polarity is similar. If the unit has a detachable power cord and IEC kind of input, the right hole should be the (+) mains, when you look at the plug front at the front.

Another simple method is to check the mains fuses. If the unit is equipped with an exterior protection fuse, release the fuse and check it by an electricity check pen while the unit is connected to the mains. It should be a (+) signal. If not, reverse the AC plug from the wall.

14. Listening Volume Level - No one can tell you that what the correct listening volume setting is. Some audiophiles like a very low listening level. Some turn the volume till the windows break.

If the outcome is to achieve the ambiance of the recorded venue, volume level should be adjusted accordingly but not more or not less. This case is applicable to acoustic instruments only and not to electronic music, jazz, or disco.

Whatever the listened record is, the correct volume setting should be the one that does not enlarge or shrink the original instrument. For instance, a guitar should be played within the original volume of the guitar, at the correct volume setting. If the volume level is increased too much, the body of the guitar will become bigger in obsolete terms. On the other hand, a full Mormon chorus would not be so realistic at low volumes.

15. Warming Up the Speakers and Cables before Critical Listening - Apart from the theory that "solid-state electronics provide their best sound for those few minutes before the transistors became warm,” practically all audio equipment needs some time to warm up. The proper time is at least half an hour or even one hour despite the manufacturers’ recommendations. The reason behind this requirement is the specifications of the resistors, capacitors, and tubes, which can vary in output if they are cold or warm. Manufacturers make final settings when the units are warm - otherwise the equipment would play perfect for the first half an hour and get worse after warming up.

Audiophiles apply this principal for their electronics but not always for their speakers and the cables. Speakers are quite important since their passive components such as crossover resistors should be warmed up. Their voice coils should be warmed up as well. The cables are also important. The term “warm up” may not apply for the cables, but the cables should be run for some time until their dielectrics are charged.

As a result, the warming-up time should be completed by playing (not necessarily listening to) the entire system.

16. Proper Loudspeaker Selection for Listening Room - Loudspeakers should be selected in conjunction with the listening room dimensions. Unfortunately the general tendency in audiophiles, particularly in the U.S., is "the bigger, the better."

It is like a starting skier picking out the best skiing equipment prior to learning and facing multiple problems afterwards.

Big loudspeakers are difficult to position, difficult to drive, and are affected the most by the room boundaries. If the speaker is too big for the room, excessive bass energy will diminish the rest of the sounds. A bigger speaker means bigger problems. Driving big speakers is challenging and requires experience, sources, time, and money.

17. PS Audio Power Plant - On principle I avoid giving specific brands in my non-commercial Website. But PS Audio Power Plant is such a special product that it is incomparable. It is a kind of power regenerator powered by electricity. P300 actually regenerates new AC for the audio gear. This regenerated AC is of much better quality than filtered AC because of the stable voltage and near-perfect AC waveform. It also removes 70 dB of EMI and RFI noise from the AC line!

Not all my friends agree, but in my opinion, it is very special equipment that lifts up the entire system to a higher level.

What you would expect from it is a much more relaxed sound, a more layered deep and wide soundstage, crystalline treble, and more inner details. Improvements are immediately apparent. Be sure to use it with power-hungry amplifiers.

18. CD Surface Treatments - There is several kinds of CD surface treatments in the market. They shine the surface of a CD so that the laser picks up more information. A surface treatment should produce high frequencies that are cleaner and more extended. The easiest and cheapest method of CD surface treatment is the one used by pipe lovers .That is the human oil on the skin of face. I apologize for that ugly tweak, but our systems are personal and private anyway, aren’t they? Human oil has the perfect thin viscosity and can be absorbed by a CD surface very easily and effectively. Listen to your CD first, then smear the CD across your forehead and spread the oil with your finger and listen to it again.

Don't forget to spread the oil with your finger every time prior to listening to that greased-up CD.

19. Objective of the Third Dimension - The objective of a stereo system is to achieve a third dimension via two channels. All hi-end or hi-fi equipment have their own character, timbre, and tonality. For instance, a titanium tweeter will have a different tonality then a silk dome tweeter. Two different brands of loudspeakers will have different tonalities even if they use the same drive units. The tonality of hi-end equipment mostly depends on the listening preferences of the designer. Most people prefer their own equipment as opposed to the different tonalities of another system, even if that other system sounds better. Most audiophiles have a bias to their own system – they don't like the sounds of somebody else's system regardless of its qualtiy. This case is also evident when buying or testing new equipment at home. We sometimes test better equipment at home but feel something is still missing when compared to our own equipment.

I remember very well, when Sony introduced the first 20-bit CD player, most of the people found the sound harsh, edgy, and colored. People were used to dark-sounding CD players at that time and hearing more inner details disturbed them.

I also remember very well that when I modified my old B&W 801 Matrix II monitor speakers and cancelled their protection units. The new sound disturbed me at first. I was so unhappy by the new sound that I could not listen to my system for several days. At that time, the manufacturer said that "the protection units were needed because the speakers were designed mainly for recording studios.” They also told to me that the new sound would be better because the system lowered crossover resistance, which affects especially the lower, mid, and upper bass ranges. After several days of listening, the sound became better and better. Eventually the sound was surprisingly perfect. Actually the sound was the same, but my perception was changing.

If this type of incident is often the case, how do we distinguish the better unit? There are several ways, but for me the main method is its third-dimension capability. This is not the only case for sure, but generally speaking, if two units are compared, the better one is the one delivers bigger soundstage, more depth, and more height.

This theory is shared with Peter Quodrup from Audio Note UK, and I am agree with him 100 percent.

The distortion of an electronic device does not affect the tonality of the equipment but mainly affects the inner details. Soundstage, depth, and height are such hidden factors in inner details that they will be affected first. If the unit provides lower distortion, more precise soundstage, especially more depth, will be provided.

20. The Least Powerful Ring of a Chain - Hi-Fi is a kind of chain. Strength of a chain depends on the least powerful ring. Picture a water hose that varies in width. Its water capacity will be in accordance with the thinnest part.

A system should consist of similar level of equipment throughout. If you add the best CD transport to a standard level of system, there will be some changes, but they won’t be as good as expected. A poor digital cable will compress the entire sound quality of a very good system.

The buyer should prepare a long-term plan before setting up a system, and the pieces should be purchased after at least some deliberation. Hurried purchases may become replacement expenses within one or two years.

21. Don't Immediately Judge a Unit, Give it a Chance - Every system can sound well in time. System synergy is a time-dependent factor that sometimes takes months, even years, to develop. Sometimes we make quick decisions, creating quick prejudices for good products, and immediately make unfair observations. From my perspective, the main element of the hi-end chain is the loudspeaker. If tonality and characteristics of the speaker are generally fine, or if the overall tonality of the entire system is generally fine, the system can be scaled up several more steps by playing with cables, tweaks, locations, and tubes, among other things.

22. Critical Adjustments should be done by Listening to Symphonic or Choral Music - Once we decide on the main components of our system, we can play with the cables, tubes, tweaks, and other accessories to find the desired tonality. But adjusting the tonal balance of a system by listening to a single instrument or jazz trios may mislead us.

Upper mid and the treble bands of a sound can easily disappear if somebody is far away from the original signal. This circumstance is the case if we listen to a live concert or hi-end system. If this is the case, such instruments like a saxophone, guitar, violin, or even the human voice are darker and more distant if we listen to a very good live record. Whenever we increase mid/treble band of the system by tweaks, these instruments will become more open, detailed, and dynamic. But one thing should be kept in mind - we may add a subtle amount of coloration to sound unconsciously. If a system is trimmed by listening to small trios, single instruments, or single voices, this risk is big. Such an adjusted system may not play classical music performed by a big orchestra. The owner should listen to symphonic music, and the system may reveal heretofore hidden harshness and brightness.

It is often said that somebody's system plays well in classics but sounds quite dark in jazz, or somebody else's system is quite revealing in jazz but very bright and glazing with classical music. These issues with system adjusts are the main reasons for those phenomena.

Hi-End is such a passionate field that many opportunist firms and persons are added every year. Despite this market growth, the hi-end community is not growing enough. Prices are multiplied by threes, five, or tens every year. Every producer pretends to be one of the best in the world or at least within a particular price level. Manufacturers issue their own review reports.

No testing equipment in today's technology can prove that their claims are correct or incorrect. Equipment cannot compare two units and prove that one sounds better than the other. Self-proclaimed best-in-the-world equipment and cables often fail to impress in blind testing. But it is easy to claim to be the best in the world if nobody can objectively prove the opposite.

The price of valuable equipment can fall down to one-third of the purchasing price within few years by the additions of MK-IIs, MK-IIIs, Special Editions, and Signature Versions.

While the best speaker in the world was sold for 7,000 € twenty years ago, the best speaker nowadays is more than 200,000 €. A poor line stage which is used to lower the volume is sold at 40,000 €.

Hi-End technologies do not mature for several years. Most of the hi-end producers are part of a small family of entrepreneurs that target a small population of very rich people. They don't have proper research and developmental laboratories. Design and aesthetic properties are the priorities.

I believe that Hi-End is digging its own grave with this policy. We will see what happens to hi-end after 30 years.

It is a deep, possibly bottomless hole. My humble recommendations are to go with secondhand products and buy reasonably priced equipment to minimize your losses over the next few years. Never look for the perfect sound, which does not exist for any amount of money. Keep in mind that an amplifier sold for 300,000 € may be only 2-3 percent better than a 5,000 € unit. In the long run, it would be worth it to buy the smaller brother.

This article was published for the 2008 CONNECTIONS™ Conference Industry Insights, the official publication of CONNECTIONS™.

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