So what are the three most important factors which no govern HiFi reproduction? They are source, speakers and your listening room and a fourth but more later.
1) The source of the music
This is the most important factor. If the source is garbage the rest of the sound reproduction in the HiFi chain will be garbage. No matter how good your equipment is, it cannot improve on the source.
1a) The master tapes: there is no reason why the original music should be badly recorded no matter whether the recording is a digital or an analogue one. Digital tape sources must be converted to analogue before an LP is made. Modern analogue to digital converters can replicate the music almost perfectly for the production of an LP pressing.
1b) Sound Engineering of the master tape: this is where things can go radically wrong, especially in the production of pop music. Compression of the dynamics of the music to make the soft parts of the music as loud as the loud parts can squeeze all the life out of the music. The loudness wars are killing music. Digital processing allows for more severe compression of the music than an LP.
Digital recording and sound reproduction caters for a much wider dynamic range than LPs. Jazz CDs and Classical Music CDs are not subjected to the compression of the music which is why they often sound better than their LP equivalents.
A compressed pop record can sound tiresome and boring. Compression of music is not a new phenomenon 45 rpm pop records were compressed to make them sound louder in the 1960s.
Some classical record radio stations also compress the music to make the soft orchestral parts louder to overcome the noise of the car when driving. This is why the music often sounds lifeless and tedious and boring.
1c) LP records and 45 rpm records: have to be pressed from a metal master which is cut on a lathe. Despite what some "audiophiles" and LP enthusiasts say, it is impossible to exactly duplicate the analogue wave form so there is always an error. This is a fact of science; the distortion of the waveform causes harmonic distortion when listening.
LP pressings usually have at least one flaw which will cause an unavoidable pop on play back.
The mere fact of pressing a diamond needle against a plastic record generates friction and noise and further harmonic distortion.
Your turntable, no matter how good it is, creates vibrations from the motor which cause rumble this is transmitted to the needle. This is unavoidable but if you use a good deck you may not be able to hear it.
A record wears out even if you use the highest quality equipment; a well worn record will sound distorted.
No matter how hard you try, you cannot avoid dust getting on a record to cause a popping noise. Likewise, static electricity is almost unavoidable and it attracts dust. Static electricity itself can cause a popping noise. The mere act of withdrawing the record from its sleeve generates static on the record.
A record can get scratched easily causing popping noises or preventing the record from playing altogether.
You can get acoustic feedback from you speakers if you site the turntable too close to a speaker and this causes the music to sound too loud and distorted.
If you do not use a solid rack, footfall can generate vibrations within the turntable or make the needle jump especially if you have floorboards. No turntable is immune to this.
It is not possible to completely separate the two channels on a stereo record . The left and right channels leak into one another; this adversely affects the "sound stage" of recordings - especially classical music. This cannot be mitigated by any equipment no matter how expensive.
I have just played a brand new record. Although I could hear very little surface noise, which
was drowned out by the music anyway, I heard one pop. Close examination of the record showed that it also had a slight scratch across the whole of the surface on one side. The record was shrink wrapped so I guess the scratch happened at the production stage. I paid a lot of money for this.
You may think why bother playing and buying LPs? Well, most of the faults can be mitigated except a scratch or dust and static. Harmonic distortion is inherent in the system but this may not spoil your musical enjoyment of pop records and jazz. But it can spoil your enjoyment of classical music. Some people actually enjoy hearing the slight harmonic distortion of the music played on a turntable and prefer the sound of an LP compared to the of a CD for this reason.
From a strictly pedantic point of view an LP cannot be high fidelity as the medium introduces harmonic distortion and popping noises from dust and static. This is distortion and noise which was not part of the original recording. Will LP "audiophiles" ever admit that LP sound reproduction is flawed? I doubt it.
The LP itself is the limiting factor for analogue sound reproduction.
Despite many of its failings , I still love playing LPs; most of mine are second hand or very old. Most of the flaws, surface noise , pops and crackles are masked by the music itself especially when playing pop or jazz.
It is classical music which really exposes the flaws; you can often hear the harmonic distortion. Cheaper decks also cause wow and flutter because they cannot control the speed of the platter's rotation accurately. The quieter bits of music expose any surface noise, scratch or pop. For classical music you need to listen to a near perfect record on very high quality equipment.
If two LPs and turntables are of HiFi quality then logic dictates that they must sound very similar. The same reasoning applies to digital music. Good quality HiFi components should sound very similar whether the source is analogue or digital. My experience bears out this conclusion.
However, logic and rationality has often gone out of the window when you read HiFi magazines and forums and blogs by "experts" and worse still advertising material.
1d) CD and other Digital recordings (including HiRes): digital recordings and their media have none of the faults of the LP listed above. They are capable of reproducing pure sound which is almost an exact duplicate of the original master tape.
A CD can be ripped to a computer WAV file which has the same quality as a CD. You can playback these files from a computer and if you use a really good DAC to connect the computer or laptop to your HiFi then the results are indistinguishable to the original CD.
A CD can reproduce musical frequencies between 20 Hz and 22 KHz. A so called HiRes digital musical file can reproduce musical frequencies between 20 Hz and 48Khz. Some digital files can reproduce music between 20 Hz and 96Khz.
No human being can hear above 22 KHz and the higher frequency range can only be heard by children. Most adults have an upper frequency limit of 15 KHz or even lower.
Most microphones only record sounds between 20 Hz and 20 kHz and most loudspeakers are limited to a similar frequency range.
Double blind scientific tests have been conducted and no-one has been proven to hear the difference between CD quality music and HiRes - with all other things being equal. HiFi magazines please take note.
Hi Res reproduction cannot provide better quality music. Any difference between CD and Hi Res is probably down to the original mastering, therefore all things are not equal when making comparisons.
I recently bought some HiRes music over the internet and downloaded it. I then converted the music to a "lower mathematical resolution" to make a CD. I could not hear the difference - all other things being equal- neither could my wife or my friends. Why is this? Our ears and perception cannot distinguish between the two. No one in a peer reviewed double blind test has been proven to hear any difference.
Anyone who can claim to hear the difference should prove this by subjecting themselves to scientific testing.
24bit/ 96 KHz files have their uses in the recording studio but for playback CD quality is good enough so enough said about this.
Technically a CD has the potential to produce higher quality music that an LP. This stands to reason and you can read all about sampling theory and practise here:
http://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_sampling_theorem.
A CD musical waveform reproduces music almost exactly. An LP does not reproduce the same waveform as accurately as it is subjected to transcription errors.
This does not mean that LPs cannot sound as satisfactory to the human ear and there are only marginal differences between high quality CD reproduction when compared to high quality LP sound reproduction.
Because the music from a CD has none of the flaws of an LP , I prefer this medium. The CD is capable of almost perfectly reproducing the music recorded on the master tape. This is especially apparent when listening to an orchestra, solo acoustic guitar, a piano performance or an opera singer. I listen to all sorts of music and prefer the CD for jazz, pop and folk music as well - especially in the soft bits.
I avoid pop music which has been dynamically compressed at the mastering stage.
There is no need for HiRes music but sometimes this music has been mastered better and has a improved dynamic range but there is no reason, for playback purposes, that CD quality cannot suffice. But of course manufacturers want to sell you equipment that has a better technical specification even though the human ear cannot perceive the so called "improved performance" of 24 bit 192 kHz music files and DACs.
You can choose to be fooled by this if you want to. But, if you have not got the money in your back pocket, I would advise that you think carefully about getting into debt to buy equipment that does not provide noticeable improvement at your ears.
CD quality is my preferred digital medium and I prefer its convenience to analogue music this is why all of my music is on CD and on hard disc drive. All the analogue music which I cannot source easily from CD has been ripped to a CD quality digital file for archive purposes and convenient playback.
As far as I am concerned there is no need for HiRes music files. The record companies should sell perfect master copies on CD for all of us to enjoy. I doubt if this will happen as I suspect that some record companies will encourage us to spend much more money on HiRes recording which is not needed.
1e) MP3 Digital Music
This is compressed music in the sense that the digital files are made smaller by removing music which you normally cannot hear. An mathematical algorithm does this. For instance when an orchestra is going at full volume you may not be able to hear a harp playing quietly.
Sometimes, a loud noise such as a drum striking causes momentary deafness to a soft piccolo playing until your ears recover. The calculation algorithms remove this soft music to make storage files smaller.
Frequencies above 15KHz can be removed as adults cannot hear them.
The modern algorithms are very good at compressing music but the quality of the sound deteriorates at lower bit rates - below 192 kbps ( kilo bits per second) - so that you can hear that the music is not CD quality which streams at 1,411 bits per second.
At 256 kbps most people cannot tell the difference between MP3 and a CD.
None of my friends can tell the difference between MP3 at 320 kbps and CD quality and neither can I even when I use a high quality DAC.
HiFi journalists are very ambivalent about MP3; normally they disparage this medium until they test Spotify on the latest wonderful DAC, when all of a sudden the music starts to sound great. You cannot have it both ways.
MP3 has its place especially on a portable player or a tablet computer and it can give HiFi quality results. Need I say more.
1f) Audio Cassettes
These are making a comeback. They have similar drawbacks to LPs. They have inherent noise hence the need for Dolby processing.
There is slight harmonic distortion inherent in their design. In fact some recording engineers and producers make use of the this to make digital recordings sound softer. But, if you copy from cassette to cassette several times the harmonic distortion becomes more readily apparent.
The tapes can stretch upon playback and distort the music further. Poorly engineered tape drives are subject to wow and flutter just like records.
Worse still the tapes can snap or unwind themselves from the cassette housing and thereby they are rendered useless. If you want to concentrate on audio cassette sound reproduction you must take back ups but if you copy a tape too many times you run into distortion problems as described before.
All my audio cassettes, which I still play in the car are backed up, to digital files so |I can make a new tape when needed. The digital copies sound exactly the same as the original. You can do this for LPs too and even with humble equipment the copy will sound almost exactly the same as the original recording. This is surely a tribute to digital technology.
I still have a high quality Sony Walkman which works really well and it can play a well recorded audio cassette at almost the same quality as an LP or a CD. The music is very satisfying to listen to.
The conversion software that I use, Audacity, can remove tape hiss and other noise - another good reason for computers and digital technology.
Many of my friends, in the 1970's, before laptops and MP3 players and CDs were heard of, copied their LPs to audio cassette so they did not have to play the vinyl so often. The audio cassettes sounded almost the same as the LP when good equipment and tapes were used for recording and playback. I never did this and that is why some of my favourite records are either heavily scratched or worn out. For this reason I converted to digital when CD was launched.
1g) Reel to Reel Analogue tapes
Most of the same reasoning applies to reel to reel tapes but in general the music reproduction is of higher quality than audio cassette. Before the advent of digital technology, analogue reel to reel tapes were used as master copies. Your original Pink Floyd, Doors, Beach Boys (1960s and 1970s) and Beatles albums would have been recorded on analogue tapes. Digital re-mastering cannot of course improve on their quality but they can be used to clean up the sound and remove noises etc.
1h) FM radio
FM radio is of HiFi quality but the frequencies cut off at 15khz. No one ever complains about this. Even though it is primarily analogue in character, somewhere along the transmission chain digital files are used to broadcast the music. So the people who rave about FM analogue sounding so much better than CD can eat their words as they are in fact listening to digital files at a lower bit rate than CD.
If you do not believe me read this:
http://www.bbceng.info/Technical%20Reviews/pcm-nicam/digits-fm.html
1j) Internet Radio, DAB and Spotify etc.
These sources can be very good provided you use very good equipment. You must listen to radio stations that broadcast at higher bit rates such as BBC Radio 3 Hi Res.
If you pay for Spotify you will receive music at almost CD quality. If you listen over a WiFi in your home then it must be set up properly.
In summary, from my experience and in my opinion CD provides the best quality sound followed very closely by: Reel to Reel tape, LP and audio cassette. I still find LPs and audio cassettes very satisfying to listen to. FM radio is very satisfying too, provided that you choose the right channel which does not compress the music. Internet radio and Spotify can be very good to listen to as well.
2) Your speakers
In my living room I have got some high quality transmission line speakers which sound great . They have an even response from the bass frequencies to the highest frequencies which are beyond my ability and most other adults to hear. The speakers top out at 20 kHz but most music produces tones at much lower frequencies.
These floor standing speakers can shift lots of air and fill the room with sound.
The bookshelf speakers that I use in the dining room are technically just as good but they do not produce bass anywhere near as well and they cannot shift as much air. So, they cannot fill the dining room with sound in the same way.
If you want the best sound reproduction you really should consider nice large speakers even if they are intrusive upon the decor of your living room.
3) Speaker position and the room
Where you position your speakers and the room that you use are one of the most important factors. The sound bounces around and sound from bare walls and floors can produce an echo sound. This is why speaker designers assume that you are using your speakers in a room with soft furniture carpets and wall coverings. Where you sit can also affect the quality of the sound and the music that you hear.
Comb filtering effects can cause interference patterns to the sound waves. Where you position yourself is important. If you change position by even a few inches the quality of the sound is affected. This is probably why foolish people hear changes to the sound when they get up to adjust the "wizzo" wooden isolation cones used to prop up a CD player or when they changed from one"wizzo" overly expensive cable to another. They have moved position and hear slight differences. At least I am trying to be charitable.
If you do not believe me read this:
http://ethanwiner.com/believe.html
Summary: where you position your speakers and yourself and the condition of your listening room has a major effect on the quality of the sound that you hear. You may not need to change your equipment fro a better listening experience, just your room and furniture and your own listening position. Yippee, you can save some money!
4) Last but not least your ears, perception, expectation and persuasion.
The Swifts flying around your roof late at night are calling to one another at 6 KHz and it is not a very pleasant sound for me. The skylark is calling at a much lower frequency and sounds much more mellifluous. Higher frequencies still sound even more piercing. So why would you want to buy musical equipment or recorded music that can reproduce the sound of a bat calling at 48 KHz. Number one you cannot hear it at all and number two it would sound awful.
Audiophiles and HiFi magazines will tell you that a moving coil cartridge can reproduce ultrasonic sounds so you must buy one. This is complete nonsense. Equipment manufactures will gladly sell you expensive equipment to reproduce sounds that you cannot hear.
Equally it is claimed that HiRes digital files sound better than CD quality when all other things are equal. They do not. The controlling features of the mathematics dictate only the frequency range of the sound and its dynamics or loudness. A 24 bit file can produce a dynamic range of 144 decibels. No sound equipment can handle this dynamic range as it would be damaged. A sound at 144 decibel of loudness would crush your ears and would likely kill you. It is simply stupid to use 24 bit music files for playback in the home.
A 96khz Hi Res file can reproduce sound frequencies up 48 KHz. This is pointless; no one can hear it and no speakers can handle these frequencies. My super duper CD and DAC uses filters to cut off frequencies above the 22.5 KHz to prevent inter modulation harmonic distortion entering into the transmission chain. In other words although my super duper DAC can process 24bit/ 96 KHz "High Resolution" files the equipment can only reproduce frequencies that a CD can handle. HiRes files are redundant as far as I am concerned.
You may well ask, why buy a new DAC that has redundant facilities? Well every new DAC has got this form of redundancy and you cannot go back to the past.
Be careful that you do not fool yourself by expecting that something that costs a lot more money will perform a lot better. A £10,000 record deck will not perform ten times better than a £1,000 one and it may sound worse if you do not set it up properly. Also, if you take into account the technical quality of an LP this could be a limiting factor. You are, after all, playing a cheap piece of plastic on a very expensive machine. The quality of the machine could be much better than the quality of the record and you may not perceive any benefit.
This same reasoning applies to CD s , Audio Cassettes and FM radio.
Your perception can also be fooled and this is what an MP3 file does; for the calculation algorithm can easily fool you into thinking that your are hearing CD quality music.
You can be fooled into thinking that, all other things being equal, you can hear a difference between HiRes music files and CD quality. But this form of foolery is caused by "audiophiles", HiFi magazines and advertising material making unjustified claims about performance so use your head and remain sceptical.
The harsh reality is that your perception can easily be fooled by auto-suggestion and by the suggestion of others.
The moon illusion is a classic example. When the moon is on the horizon it appears a lot bigger than the moon high in the sky but it is the same size and can be covered by a coin or a pea at arms length. Try it.
Every person on the planet sees this moon illusion despite their culture or up bringing. You cannot overcome the illusion even though it has been explained to you.
http://www.grand-illusions.com/opticalillusions/moon/
So there you have it the prime factor in the perception of sound quality of music is the source material. The speakers and their position and your position in the room also greatly affect the quality.
But, please be aware that overriding all of this is your expectation, perception and the quality of your hearing. Please be aware also of the power of persuasion.
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