Someone reading these pages might get the impression that I am opposed to new developments in technology and that I do not believe that we will be able to improve sound quality. This is not so. I am all in favour of new recording and sound reproduction techniques which will enable us to achieve improved Hi-Fi performance.
It is obvious that current Hi-Fi recording techniques and sound reproduction are unable to exactly duplicate the original performance whether that is in the studio or live. This is especially apparent when related to classical music. For many reasons including microphone placement, transducer performance and listening room acoustics a sound recording cannot exactly duplicate the original music. We are able to reproduce a flat frequency response. We are able to reproduce musical frequencies well beyond the bounds of human hearing. Likewise we can record and playback music which has a very wide dynamic range beyond even the loudest and softest notes that a full orchestra can manage. We can playback music at loudness levels which can easily damage human hearing.
We can do most of this with a humble LP and a CD can achieve this easily. There is no need for "High Resolution" digital music files which can push the parameters further than CD. It is absolutely pointless to reproduce frequencies above the ability of any human to hear i.e. above 20 KHz. It is equally pointless to enable the playback of music files which allow for a dynamic range of 140 db or more. To exploit this would damage reproduction equipment and worse of all would permanently damage the hearing of the listener in short order.
Manufacturers are leading us up a stereo dead end and playing a numbers game. They have the right to claim that their equipment is better but they have a moral duty not to mislead the public.
Manufacturers are being supported in this numbers game by Hi-Fi magazines whose reporters claim that they can hear sounds and quality differences which science says they cannot. I believe that they are being disingenuous. Add to this the comments and exaggerated claims which are made on some Hi-Fi forums for turntables, cables, "Hi-Res" versus Cd etc. and we are in a sorry mess.
There is room for improvement in sound technology but based on scientific and engineering research which can identify genuine improvements which can be made to inter alia:
microphones and their placement,
loudspeakers,
room acoustics
and computer generated surround sound systems.
We will never progress while false and unverifiable claims are made for 24/192, DSD sound reproduction. No improvement will be made whilst some "audiophiles" believe that electrons somehow follow the arrows printed on expensive cables - they do not. Electrons flow from negative to positive polarity.
How can we progress when people believe that hanging little rocks from line input connexions can improve sonic performance.
The time has come to stop all the myths and apply some genuine science and sound engineering to solve Hi-Fi problems.
It is a pity that Hi-Fi magazines feel that they cannot support science and that most reporters are only interested in playing the numbers game.
Wednesday, 1 July 2015
Thursday, 25 June 2015
Don't be fooled by the new fashion to buy a turntable because the sound of LP's are so wonderful
I have been listening to LPs since the mid 1960s and I think that they can sound great and they can also sound awful. Nearly everyone is getting onto the turntable band wagon. Hi-Fi magazines and forums are full of praise for the new rise of analogue music. Most of the comments that you will read are exaggerated or untrue.
The first mistruth is that technically LPs are more proficient at Hi-Fi sound reproduction than CDs or "HiRes" digital files. This assertion does not stand up to scrutiny; the whole system of LP sound reproduction (and 45s and 78s) is flawed from start to finish and introduces excessive harmonic distortion and clicks and pops and timing errors and that is before you slide the LP out of its cover and play it. Vinyl pedants claim that analogue sound reproduction can be perfect - no it cannot - clicks and pops are unavoidable. And, from a pedantic point of view if you hear one pop which should not be there then you are not listening to Hi-Fi.
I love listening to LPs on occasion but when I do it is for fun and for the different sound from "digital" music. For serious musical appreciation I choose digital sources.
Deciding what equipment to buy can be a nightmare for the uninitiated. There is so much exaggeration and hyperbole written about the subject of turntables and LPs that it is difficult to find sound advice.
Most of the budget turntables are perfectly capable of giving good sound reproduction. The likes of Pioneer, Project, Marantz, Sony, Music Hall etc. all have reputations to maintain and they are not going to sell you a product which does not sound good. Some of these turntables are made of plastic and are a bit flimsy but if you place them on a solid rack or shelf they will perform well. The cheap turntables will suffer from quality control issues so that the odd one will suffer from wow or flutter or speed variations; in which case you return it to the supplier. To get reasonable sound reproduction ensure that your turntable has a moving magnet cartridge rather than a ceramic one.
Most of the criticism on forums relates to the fact that the cheap budget turntables are made of plastic. Well consider this, vinyl is plastic and many expensive decks have acrylic plinths or platters and what is acrylic if it is not plastic? The solidity and weightiness of a good deck helps to reduce vibration but if you site your budget deck on a solid platform its flimsiness is mitigated.
On many forums budget turntables are dismissed as junk or rubbish but a budget turntable maybe all you can afford so do not let this opinion put you off. Try them for yourself and if they are no good return them to the supplier.
When you buy a turntable, you do not want to damage your records because of excessive down force or stylus pressure especially if you have bought an expensive 180gm vinyl record. Many audiophiles get anal about this and constantly tinker with down force and may even reset it every time they play a record. Some set this to the minimum; my cartridge has a down force range of 1.5gms to 2.5gms. I have set mine to 2.2gms and I see no reason to change it. Many budget tables use a pre-set or unchangeable down force of 3.5gms. Such a force would be traduced by an audiophile but I do not think that this will damage your records even after repeated playing.
If you digitise your records properly to a 16/44.1 Wav file using a good USB deck or USB phono-stage then you can reserve playing the LP for special occasions to avoid wear and tear. The digital file will sound almost exactly the same as the LP.
Many contributors to forums and magazines criticise turntables with built in phono-stages. Well I have got two such turntables and they both sound fantastic. When I use an external phono-stage they hardly sound any different. Phono-stages use electronics to amplify the weak signal of a moving magnet cartridge and they also equalise the sound according to RIAA standards. When a record is cut the bass is attenuated and the treble is accentuated this is reversed by the phono-stage. RIAA equalisation has been around since the mid 1950's so there has been plenty of time for Pioneer, Sony, Project, Teac and Denon etc. to get this right. You do not need to spend hundreds of pounds for a simple phono-stage.
There is so much exaggeration and unjustified criticism I could go on forever. Just remember that the commentators on forums and in magazines rarely make comparisons to a standard in fact they almost never do. When they are making their judgements, they never do so on the basis of double blind testing . All the comment is mostly based on asserted hearsay rather than facts established by the scientific method.
If you want to then you can buy a moving coil cartridge that will playback ultra-sonic sound up to 45khz; but the trouble is no-one can hear sound with a higher frequency than 20kHz (reserved for children) and for many adults their highest frequency is much lower. So you may well ask what is the point of a moving coil cartridge? Many audiophiles do not ask this question. Most LPs do not have musical content above 15khz.
When you read a forum that traduces your potential purchase just remember this: when the Beatles and the Rolling Stones first started making records we played their music on Dansette type record players with poorly produced and specified ceramic cartridges with a down force of about 10gms. The music still sounded good enough for the Beatles and the Stones etc. to sell millions of records.
The other day I was at a market where someone was selling second hand records and he was playing them on a real budget job - less than £100 pounds. It sounded better than our Dansettes. Why not try a cheap turntable if you cannot decide if the medium suits you or not but buy some second hand records to play on it? You can always upgrade later.
Also consider this, a £30,000 pound turntable can sound marvellous and I would never criticise someone who bought one. However, the £30,000 record player gives you the ultimate in sound reproduction which includes the music and the clicks and pops and surface noise which cannot be removed no matter how much you spend, because the system is flawed sonically from start to finish. Try listening to a 180gm acoustic music vinyl LP but with headphones and then you will see what I mean.
The first mistruth is that technically LPs are more proficient at Hi-Fi sound reproduction than CDs or "HiRes" digital files. This assertion does not stand up to scrutiny; the whole system of LP sound reproduction (and 45s and 78s) is flawed from start to finish and introduces excessive harmonic distortion and clicks and pops and timing errors and that is before you slide the LP out of its cover and play it. Vinyl pedants claim that analogue sound reproduction can be perfect - no it cannot - clicks and pops are unavoidable. And, from a pedantic point of view if you hear one pop which should not be there then you are not listening to Hi-Fi.
I love listening to LPs on occasion but when I do it is for fun and for the different sound from "digital" music. For serious musical appreciation I choose digital sources.
Deciding what equipment to buy can be a nightmare for the uninitiated. There is so much exaggeration and hyperbole written about the subject of turntables and LPs that it is difficult to find sound advice.
Most of the budget turntables are perfectly capable of giving good sound reproduction. The likes of Pioneer, Project, Marantz, Sony, Music Hall etc. all have reputations to maintain and they are not going to sell you a product which does not sound good. Some of these turntables are made of plastic and are a bit flimsy but if you place them on a solid rack or shelf they will perform well. The cheap turntables will suffer from quality control issues so that the odd one will suffer from wow or flutter or speed variations; in which case you return it to the supplier. To get reasonable sound reproduction ensure that your turntable has a moving magnet cartridge rather than a ceramic one.
Most of the criticism on forums relates to the fact that the cheap budget turntables are made of plastic. Well consider this, vinyl is plastic and many expensive decks have acrylic plinths or platters and what is acrylic if it is not plastic? The solidity and weightiness of a good deck helps to reduce vibration but if you site your budget deck on a solid platform its flimsiness is mitigated.
On many forums budget turntables are dismissed as junk or rubbish but a budget turntable maybe all you can afford so do not let this opinion put you off. Try them for yourself and if they are no good return them to the supplier.
When you buy a turntable, you do not want to damage your records because of excessive down force or stylus pressure especially if you have bought an expensive 180gm vinyl record. Many audiophiles get anal about this and constantly tinker with down force and may even reset it every time they play a record. Some set this to the minimum; my cartridge has a down force range of 1.5gms to 2.5gms. I have set mine to 2.2gms and I see no reason to change it. Many budget tables use a pre-set or unchangeable down force of 3.5gms. Such a force would be traduced by an audiophile but I do not think that this will damage your records even after repeated playing.
If you digitise your records properly to a 16/44.1 Wav file using a good USB deck or USB phono-stage then you can reserve playing the LP for special occasions to avoid wear and tear. The digital file will sound almost exactly the same as the LP.
Many contributors to forums and magazines criticise turntables with built in phono-stages. Well I have got two such turntables and they both sound fantastic. When I use an external phono-stage they hardly sound any different. Phono-stages use electronics to amplify the weak signal of a moving magnet cartridge and they also equalise the sound according to RIAA standards. When a record is cut the bass is attenuated and the treble is accentuated this is reversed by the phono-stage. RIAA equalisation has been around since the mid 1950's so there has been plenty of time for Pioneer, Sony, Project, Teac and Denon etc. to get this right. You do not need to spend hundreds of pounds for a simple phono-stage.
There is so much exaggeration and unjustified criticism I could go on forever. Just remember that the commentators on forums and in magazines rarely make comparisons to a standard in fact they almost never do. When they are making their judgements, they never do so on the basis of double blind testing . All the comment is mostly based on asserted hearsay rather than facts established by the scientific method.
If you want to then you can buy a moving coil cartridge that will playback ultra-sonic sound up to 45khz; but the trouble is no-one can hear sound with a higher frequency than 20kHz (reserved for children) and for many adults their highest frequency is much lower. So you may well ask what is the point of a moving coil cartridge? Many audiophiles do not ask this question. Most LPs do not have musical content above 15khz.
When you read a forum that traduces your potential purchase just remember this: when the Beatles and the Rolling Stones first started making records we played their music on Dansette type record players with poorly produced and specified ceramic cartridges with a down force of about 10gms. The music still sounded good enough for the Beatles and the Stones etc. to sell millions of records.
The other day I was at a market where someone was selling second hand records and he was playing them on a real budget job - less than £100 pounds. It sounded better than our Dansettes. Why not try a cheap turntable if you cannot decide if the medium suits you or not but buy some second hand records to play on it? You can always upgrade later.
Also consider this, a £30,000 pound turntable can sound marvellous and I would never criticise someone who bought one. However, the £30,000 record player gives you the ultimate in sound reproduction which includes the music and the clicks and pops and surface noise which cannot be removed no matter how much you spend, because the system is flawed sonically from start to finish. Try listening to a 180gm acoustic music vinyl LP but with headphones and then you will see what I mean.
Tuesday, 19 May 2015
HIFI magazines and Forums
As far as I am concerned HIFI magazines have a duty to be objective. Sometimes I doubt their sincerity. All sorts of claims are made about the reviewers' abilities to notice "night and day" differences between reproduction equipment and digital music file formats -24/96 and 16/44.1 etc.
With regard to equipment, amplifiers should sound very similar,all other things being equal, if they are of HIFI quality: this just stands to reason. When the magazines provide measurement data amplifiers show similar characteristics from a measurement point of view. When listening tests are made of amplifiers there is never any attempt to implement double blind testing. The reader is offered no form of evidence as to which is the better amplifier.
The same applies to all other forms of equipment CD players, Turntables, Cartridges, Cables, Mains filters etc. There is never any evidence. It is egregious that before and after measurements are not made in the case of cables or mains filters. The only evidence seems to be that expensive is good and the more expensive the better.
Similarly for digital file formats, the HIFI magazine reviewers always claim that in their listening tests 24/96, 24/192 or DSD files sound better than 16/44.1. There is no evidence that anyone can regularly tell the difference, all other things being equal, between such files. There is not much evidence that anyone can hear the difference between a 320 kbps MP3 digital file and a 24/96 digital file. Still the HIFI magazines persist in making claims that they can hear night and day differences. What makes their hearing so special? If their hearing is so special let them prove it by submitting themselves to scientific testing. I doubt that that they ever will.
HIFI forums have no such duty to be objective but most of them repeat the same errors. They will traduce equipment that they do not like and half the time I suspect that they have not heard the kit they are criticising. Most of the opinions on most of the forums are bunkum.
This one is a notable exception as it makes an attempt to be objective and scientific and I think it succeeds.
http://www.head-fi.org/t/486598/testing-audiophile-claims-and-myths
There must be others and it is worth finding them.
How about this?
http://www.harbeth.co.uk/usergroup/showthread.php?1663-Double-Blind-Testing-(DBT)-and-a-refutation-of-the-A-B-listening-experience&p=19876
What is Joe Public to do when buying HIFI? Trust his own ears - that is all but buyer beware.
With regard to equipment, amplifiers should sound very similar,all other things being equal, if they are of HIFI quality: this just stands to reason. When the magazines provide measurement data amplifiers show similar characteristics from a measurement point of view. When listening tests are made of amplifiers there is never any attempt to implement double blind testing. The reader is offered no form of evidence as to which is the better amplifier.
The same applies to all other forms of equipment CD players, Turntables, Cartridges, Cables, Mains filters etc. There is never any evidence. It is egregious that before and after measurements are not made in the case of cables or mains filters. The only evidence seems to be that expensive is good and the more expensive the better.
Similarly for digital file formats, the HIFI magazine reviewers always claim that in their listening tests 24/96, 24/192 or DSD files sound better than 16/44.1. There is no evidence that anyone can regularly tell the difference, all other things being equal, between such files. There is not much evidence that anyone can hear the difference between a 320 kbps MP3 digital file and a 24/96 digital file. Still the HIFI magazines persist in making claims that they can hear night and day differences. What makes their hearing so special? If their hearing is so special let them prove it by submitting themselves to scientific testing. I doubt that that they ever will.
HIFI forums have no such duty to be objective but most of them repeat the same errors. They will traduce equipment that they do not like and half the time I suspect that they have not heard the kit they are criticising. Most of the opinions on most of the forums are bunkum.
This one is a notable exception as it makes an attempt to be objective and scientific and I think it succeeds.
http://www.head-fi.org/t/486598/testing-audiophile-claims-and-myths
There must be others and it is worth finding them.
How about this?
http://www.harbeth.co.uk/usergroup/showthread.php?1663-Double-Blind-Testing-(DBT)-and-a-refutation-of-the-A-B-listening-experience&p=19876
What is Joe Public to do when buying HIFI? Trust his own ears - that is all but buyer beware.
Tuesday, 21 April 2015
"360" sound on an Erroll Garner LP
I bought a brand new 180 gm virgin vinyl LP the other day featuring Erroll Garner - " Concert By The Sea". It was released by Columbia records who are now part of the Sony Music entertainment group.
The LP was originally recorded in 1956. It sounds fantastic and a far as I am concerned Erroll Garner is a genius of jazz; I could listen to his records all day. He can even play musical jokes that get me smiling.
Columbia records claim that they use quality control methods at every stage of the record producing process to ensure absolute high fidelity sound reproduction. Their record is able to cover the full frequency range of a high fidelity recording from 30Hz to 15khz within a 2 decibel tolerance. I have no reason to doubt this claim as the sound reproduction is wonderful even though the original recording was made with equipment from 1956.
The frequency range encompasses all of the musical frequencies that most adults can hear. The LP itself has very little surface noise and at the volumes that I use I could not hear any surface noise between the tracks. My modest turntable runs so quietly that I could not hear any noise from the equipment itself, and I could hear no wow and flutter from the piano which means that the platter was running at a more or less constant speed and that the spindle hole of the record is accurately positioned. All in all listening was an enjoyable Hi-Fi experience. The record sounded almost as good as a well mastered CD recording.
The frequency response of my moving magnet cartridge is from 20 Hz to 20KHz. A moving coil cartridge is capable of producing a much wider range of frequency response. But I ask myself the question why should I change the cartridge when a moving magnet cartridge already encompasses all the frequencies that the record can produce with a considerable amount of headroom.
I could invest in an improved turntable to reduce noise and distortion but why should I? The record and turntable combination are already so good that they compete with a cd as far as high fidelity is concerned.
I am going to digitise the record. I shall convert the recording to a 16/44.1 WAV file - cd quality. This resolution can easily encompass the dynamic range and frequency response of the record. A cd quality file can manage a dynamic range of 96 decibels which is much more than an LP record can and it can cover a frequency range of 20Hz to 22Khz. This is all the resolution that is needed.
If I am to believe some of the comment on Hi-Fi forums and all of the comment in Hi-Fi magazines then I need to spend a lot more money on cartridges, cables, heavy weight platters, phono-stages, power supplies etc. to achieve Hi-Fi nirvana: I do not.
If I am to believe the same media when I come to digitise the records then I need to use "high resolution" files - 24/96 or even 24/192 to digitise the LP: I do not as "high resolution" files sound no better than 16/44.1.
Most of what is written about Hi-Fi is irrational bunkum without any supporting evidence using measurements which take into account the limits of human hearing. Usually no one provides any evidence from double blind listening tests. Most commentary regarding the quality of sound reproduction is useless. You are better off deciding for yourself.
One form of advice is sensible , however, to ensure the longevity of the LP listening experience it is best to digitise your LPs as soon as you can after buying them. In this way you can protect them from scratches, dust and dirt and static build up. You then only need to play the actual vinyl record on a special occasion or when you are in the mood. A good digital recording will sound exactly like the original.
If you cannot bear the thought of digital then why not copy them to audio-cassette? A well recorded cassette will sound almost as good as the original but it will wear out and you will have to repeat the process after a few years - even so this is a good way to preserve you records and you can still look at the sleeve when you play the facsimile!
The LP was originally recorded in 1956. It sounds fantastic and a far as I am concerned Erroll Garner is a genius of jazz; I could listen to his records all day. He can even play musical jokes that get me smiling.
Columbia records claim that they use quality control methods at every stage of the record producing process to ensure absolute high fidelity sound reproduction. Their record is able to cover the full frequency range of a high fidelity recording from 30Hz to 15khz within a 2 decibel tolerance. I have no reason to doubt this claim as the sound reproduction is wonderful even though the original recording was made with equipment from 1956.
The frequency range encompasses all of the musical frequencies that most adults can hear. The LP itself has very little surface noise and at the volumes that I use I could not hear any surface noise between the tracks. My modest turntable runs so quietly that I could not hear any noise from the equipment itself, and I could hear no wow and flutter from the piano which means that the platter was running at a more or less constant speed and that the spindle hole of the record is accurately positioned. All in all listening was an enjoyable Hi-Fi experience. The record sounded almost as good as a well mastered CD recording.
The frequency response of my moving magnet cartridge is from 20 Hz to 20KHz. A moving coil cartridge is capable of producing a much wider range of frequency response. But I ask myself the question why should I change the cartridge when a moving magnet cartridge already encompasses all the frequencies that the record can produce with a considerable amount of headroom.
I could invest in an improved turntable to reduce noise and distortion but why should I? The record and turntable combination are already so good that they compete with a cd as far as high fidelity is concerned.
I am going to digitise the record. I shall convert the recording to a 16/44.1 WAV file - cd quality. This resolution can easily encompass the dynamic range and frequency response of the record. A cd quality file can manage a dynamic range of 96 decibels which is much more than an LP record can and it can cover a frequency range of 20Hz to 22Khz. This is all the resolution that is needed.
If I am to believe some of the comment on Hi-Fi forums and all of the comment in Hi-Fi magazines then I need to spend a lot more money on cartridges, cables, heavy weight platters, phono-stages, power supplies etc. to achieve Hi-Fi nirvana: I do not.
If I am to believe the same media when I come to digitise the records then I need to use "high resolution" files - 24/96 or even 24/192 to digitise the LP: I do not as "high resolution" files sound no better than 16/44.1.
Most of what is written about Hi-Fi is irrational bunkum without any supporting evidence using measurements which take into account the limits of human hearing. Usually no one provides any evidence from double blind listening tests. Most commentary regarding the quality of sound reproduction is useless. You are better off deciding for yourself.
One form of advice is sensible , however, to ensure the longevity of the LP listening experience it is best to digitise your LPs as soon as you can after buying them. In this way you can protect them from scratches, dust and dirt and static build up. You then only need to play the actual vinyl record on a special occasion or when you are in the mood. A good digital recording will sound exactly like the original.
If you cannot bear the thought of digital then why not copy them to audio-cassette? A well recorded cassette will sound almost as good as the original but it will wear out and you will have to repeat the process after a few years - even so this is a good way to preserve you records and you can still look at the sleeve when you play the facsimile!
Friday, 13 March 2015
Beatles LPs and broken promises
I broke a promise that I made to myself about not buying the newly re-mastered Beatles mono LPs . I bought a couple to see what all the furore was about on impulse without listening to my rational brain. Well I am not going to indulge anymore.
I have been listening to LPs for years and I have always been annoyed by any sort of wow and flutter, static hiss, groove noise and crackles.
I recently bought a copy of King Crimson's " In the Court of the Crimson King" in 200 gm virgin vinyl. When I first played it, it sounded perfect. However, it did not sound any better than the CD version.
I have played the record 3 times now and already static crackle and dust clicks are affecting the quiet parts of the album. This accumulation of static and dust cannot be prevented.
The same thing is happening to the couple of The Beatles mono re-masters that I have bought. If I keep playing them they will end up sounding like my 1963 copy of "With The Beatles" which has got plenty of static noise in between the tracks even though it is not damaged or worn out. I will end up thinking why did I bother buying the new records. New vinyl should only really be played on special occasions - you are better off digitising the records to 16/44.1 Wav or Flac music files which reproduce the vinyl sound exactly the same, or buying the CD if it has been mastered at a good quality which the new Beatles CD re-masters have been and so has the King Crimson. With a CD you benefit from an album which is free of surface noise, wow and flutter and crackle - genuine hi-fi.
I have been listening to LPs for years and I have always been annoyed by any sort of wow and flutter, static hiss, groove noise and crackles.
I recently bought a copy of King Crimson's " In the Court of the Crimson King" in 200 gm virgin vinyl. When I first played it, it sounded perfect. However, it did not sound any better than the CD version.
I have played the record 3 times now and already static crackle and dust clicks are affecting the quiet parts of the album. This accumulation of static and dust cannot be prevented.
The same thing is happening to the couple of The Beatles mono re-masters that I have bought. If I keep playing them they will end up sounding like my 1963 copy of "With The Beatles" which has got plenty of static noise in between the tracks even though it is not damaged or worn out. I will end up thinking why did I bother buying the new records. New vinyl should only really be played on special occasions - you are better off digitising the records to 16/44.1 Wav or Flac music files which reproduce the vinyl sound exactly the same, or buying the CD if it has been mastered at a good quality which the new Beatles CD re-masters have been and so has the King Crimson. With a CD you benefit from an album which is free of surface noise, wow and flutter and crackle - genuine hi-fi.
Radio 4 on my Hi-Fi turntable with RFI
I
once lived very near the Crystal Palace transmitter in London, way back in the 1970s, and
I heard lots of Radio Frequency Interference (RFI). It was not in the form
of frame-buzz but I actually heard Radio 4 loud and clear.
Just
imagine my horror when, intermittently, I heard Dan Archer from " The Archers" - an every day story of country folk - prattling along to
the softer parts of a progressive rock album. It took performance art to a new
absurd and surreal level. I never really indentified where the problem lay or
cured it. I guessed that the mains-cabling was acting as an antenna and that my
turntable cartridge was acting as a rectifier.
I moved house and that eliminated the problem.
I
have never experienced any problem with RFI since then. The house is now full
of wireless equipment and portable ‘phones etc. but “The Archers” no longer
spoil the music. I thought that modern technology had banished RFI
intrusion forever but it seems that some people still suffer from it.
Quite often there is a simple solution. Making sure all your connexions are tight. Using screened interconnects, mains cables and speaker cables can also work. Usually the process of elimination can identify where the problem is. Even moving your cables around can work. None of this need expensive. There is no need to spend a fortune on expensive cables which have never been proven to work better than standard quality cables at much lower prices.
RFI can sometimes be alleviated by the use of cheap ferrite rings.
http://www.amazon.co.uk/Movable-Offset-UF50B-Diameter-Ferrite/dp/B007Q94DMO/ref=sr_1_1?ie=UTF8&qid=1426250880&sr=8-1&keywords=ferrite+rings#customerReviews
Quite often there is a simple solution. Making sure all your connexions are tight. Using screened interconnects, mains cables and speaker cables can also work. Usually the process of elimination can identify where the problem is. Even moving your cables around can work. None of this need expensive. There is no need to spend a fortune on expensive cables which have never been proven to work better than standard quality cables at much lower prices.
RFI can sometimes be alleviated by the use of cheap ferrite rings.
http://www.amazon.co.uk/Movable-Offset-UF50B-Diameter-Ferrite/dp/B007Q94DMO/ref=sr_1_1?ie=UTF8&qid=1426250880&sr=8-1&keywords=ferrite+rings#customerReviews
Monday, 9 March 2015
Hi-Fi Nous - There is a difference between believing something to be true and knowing something to be true
The BBC broadcasts its classical music station Radio3 on FM and many audiophile enthusiasts believe that Radio 3 broadcasts sound better than "CD quality". These enthusiasts believe that they are listening to a fully analogue audio signal.
Well they are not; ever since the 1970s the BBC has built a digital circuit in the transmission chain to improve the propagation of the audio signal through landlines on their way to the transmitter.
As far as practicality is concerned Radio 3 listeners are listening to a digital radio signal which is broadcast using an analogue carrier wave.
Starting from 1972 The BBC used PCM digital circuits to convert their analogue music signals at a 13 bit/32khz sampling rate. This effectively meant that that Radio 3 audio had a theoretical dynamic range of 78 decibels and an upper frequency limit of 16khz for the music. The frequency limit was further restricted to 15khz because of a bandwidth restriction associated with Frequency Modulated radio broadcasting.
Since the 1980s, The BBC has been using 14 bit/32khz Nicam digital processors.
The Radio 3 FM broadcasts of classical music can sound wonderful and at a bit rate of around 720 kbps they sound just as good to my ears as a CD transcribing around 1400 kbps. The BBC has recently started internet broadcasts of Radio 3 using a 320 kbps AAC codec and this sounds wonderful too.
If you still want to believe that you are listening to a wonderful analogue hi-fi experience when you tune in to R3 FM then think again. There is a difference between believing something to be true and knowing it to be true.
http://www.audiomisc.co.uk/BBC/PCMandNICAM/History.html
Well they are not; ever since the 1970s the BBC has built a digital circuit in the transmission chain to improve the propagation of the audio signal through landlines on their way to the transmitter.
As far as practicality is concerned Radio 3 listeners are listening to a digital radio signal which is broadcast using an analogue carrier wave.
Starting from 1972 The BBC used PCM digital circuits to convert their analogue music signals at a 13 bit/32khz sampling rate. This effectively meant that that Radio 3 audio had a theoretical dynamic range of 78 decibels and an upper frequency limit of 16khz for the music. The frequency limit was further restricted to 15khz because of a bandwidth restriction associated with Frequency Modulated radio broadcasting.
Since the 1980s, The BBC has been using 14 bit/32khz Nicam digital processors.
The Radio 3 FM broadcasts of classical music can sound wonderful and at a bit rate of around 720 kbps they sound just as good to my ears as a CD transcribing around 1400 kbps. The BBC has recently started internet broadcasts of Radio 3 using a 320 kbps AAC codec and this sounds wonderful too.
If you still want to believe that you are listening to a wonderful analogue hi-fi experience when you tune in to R3 FM then think again. There is a difference between believing something to be true and knowing it to be true.
http://www.audiomisc.co.uk/BBC/PCMandNICAM/History.html
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