Is High Fidelity possible?2019-02-18T17:33:42+00:00

Is High Fidelity possible?

High Fidelity originally means a faithful reproduction of the sound of the concert hall, and in the average concert hall seat the sound alone did not give us pinpoint accuracy.  What we today demand from our stereo equipment is to have the total experience, which our eyes and ears give us together in the concert hall, but without the 70% information from the eyes!

The human ears provide a small amount of information for our brain compared to the information which our eyes provide.  Our eyes represent roughly 70% of the information the brain receives as input, and the information from the eyes overrules information from the ears.

So when we sit in a classical music concert hall, we see the instruments more than we hear them.  Therefore we can accept seats to the left or the right side of the concert hall, although at home we want to sit in the center.

In the concert hall we locate instruments with our eyes, and we can do this very precisely at a large distance. If we close our eyes, we are not able to pinpoint one violin from the next violin.  We can still hear it, when one of the violins plays one wrong note, but we cannot say it was number 4 or number 5 counting from the left side.

We are in most seats sitting far from the orchestra, and from our position, the angle from the extreme left violin to the extreme right bass is less than 90 degrees and often less than 60 degrees.

We are also so far away from the orchestra, that we listen mainly to the diffuse reverb coming from everywhere in the hall. The direct sound level is low compared to the reverb sound level.  It is the direct sound our ears use to give us directional information. So our ears have problems with giving us a pinpoint accurate position of that wrong playing violin.

Only the conductor can hear which violin played the wrong note. The reason is, that the conductor is placed so close to the orchestra, and they are spread around him in a half circle, 180 degrees.  Also he is so close to the instruments, so he hears a much higher direct sound level compared to us.  This unfortunately means, that the orchestra sound, which the conductor is used to hearing, and the orchestra sound, which we hear in the concert hall, are two very different sounds. So the conductor is not able to judge how a good recording should be.

The late recordings of Karajan and the early recordings illustrates this very well. The late recordings were made according to Karajan’s ideals, they sound very different from the experience of concert listeners.

At home listening to music recordings on CDs or LPs we only have our ears. So our ears have to provide more precise directional information, so that instead of using our eyes, we can “SEE” with our ears. So we demand both from our CDs and from our stereo equipment more pinpoint accuracy, than we demand from the actual concert experience!

In early stereo recordings, the difference between left and right was exciting news for home listener. Later we became more demanding and wanted a nice spread of instrument between the left and right loudspeakers. Later still we began demanding depth too, and today we demand from our stereo reproduction that we can almost “SEE” the walls of the concerts hall and “SEE” the space around each instrument and the distance to the next instrument.

This is much more than we demand in the concert hall. So we are demanding more than the term High Fidelity means!  High Fidelity originally means a faithful reproduction of the sound of the concert hall, and in the average concert hall seat the sound alone did not give us pinpoint accuracy.  What we today demand from our stereo equipment is to have the total experience, which our eyes and ears give us together in the concert hall, but without the 70% information from the eyes!

What can we do to help our ears with “seeing” better, and giving our brain some of the missing information?

We can try placing the microphone at the conductors position. There we have a lot of directional information.  But we get a 180 degree perspective, like a bird eye lens. We also get too much direct sound, and we want to hear the reverb of the hall too.   If we move the microphone away from the orchestra, the perspective becomes more normal, and we get more reverb from the hall. But we start loosing directional information for each step away from the orchestra, so we must choose a compromise somewhere between the conductor podium and the average seat in the hall. Note that we have to use a center seat for the recording, otherwise the balance left to right goes wrong.

Moving a microphone around to find the best sound is very time consuming, so it is seldom done.  We can start using support microphones near some of the instruments, and blend them with the main stereo microphone. The sound travels slowly, only 340 m/s, so just 10 meters distance between the main microphone and the support microphone give us 30 ms delay, which we hear as an echo.

Now we have to consider another problem. Air is not perfect, at say 20 meters distance it absorbs treble more than bass. And the reverb sound is made by reflections from the walls far away.  So close to the orchestra, the microphones hear much more treble, than we hear in a normal seat.

Stereo recording have been made for about 40 years, and many different recording methods have been tried. I find that the best recordings were made in the time from 1957-1968. In this period, the recording engineers did not have so many microphones as today and only 2 or 3 tracks on the tape machines.

Artists often produce their best work, when they are constrained. In this case the limitations of technology meant that both musicians and engineers had to work together to get the right balance from a single stereo microphone. So instead of adjusting the flute level in the mixing console, the conductor had to ask the flute player to play softer or louder.  The engineer too was constrained. He had to find the best place for the single microphone. A place where all aspects of the performance was captured.

But the stereo equipment of this period was not able to reproduce the quality of these recordings.  Only today we can begin to reproduce the 3 dimensional space captured in these old recordings and learn from these old recordings something important about High Fidelity.

A good example is the EMI Classics recording of Carmen on CDS 7 54368 2 stereo. (Only this number, later CD transfer of the original analogue master tape is not that good). In the end of act II you will hear a singer both singing and walking across the stage and then from the back of the stage towards the microphone. The recording was done in 1964.

Ole Lund Christensen

The human ears provide a small amount of information for our brain compared to the information which our eyes provide.  Our eyes represent roughly 70% of the information the brain receives as input, and the information from the eyes overrules information from the ears.

So when we sit in a classical music concert hall, we see the instruments more than we hear them.  Therefore we can accept seats to the left or the right side of the concert hall, although at home we want to sit in the center.

In the concert hall we locate instruments with our eyes, and we can do this very precisely at a large distance. If we close our eyes, we are not able to pinpoint one violin from the next violin.  We can still hear it, when one of the violins plays one wrong note, but we cannot say it was number 4 or number 5 counting from the left side.

We are in most seats sitting far from the orchestra, and from our position, the angle from the extreme left violin to the extreme right bass is less than 90 degrees and often less than 60 degrees.

We are also so far away from the orchestra, that we listen mainly to the diffuse reverb coming from everywhere in the hall. The direct sound level is low compared to the reverb sound level.  It is the direct sound our ears use to give us directional information. So our ears have problems with giving us a pinpoint accurate position of that wrong playing violin.

Only the conductor can hear which violin played the wrong note. The reason is, that the conductor is placed so close to the orchestra, and they are spread around him in a half circle, 180 degrees.  Also he is so close to the instruments, so he hears a much higher direct sound level compared to us.  This unfortunately means, that the orchestra sound, which the conductor is used to hearing, and the orchestra sound, which we hear in the concert hall, are two very different sounds. So the conductor is not able to judge how a good recording should be.

The late recordings of Karajan and the early recordings illustrates this very well. The late recordings were made according to Karajan’s ideals, they sound very different from the experience of concert listeners.

At home listening to music recordings on CDs or LPs we only have our ears. So our ears have to provide more precise directional information, so that instead of using our eyes, we can “SEE” with our ears. So we demand both from our CDs and from our stereo equipment more pinpoint accuracy, than we demand from the actual concert experience!

In early stereo recordings, the difference between left and right was exciting news for home listener. Later we became more demanding and wanted a nice spread of instrument between the left and right loudspeakers. Later still we began demanding depth too, and today we demand from our stereo reproduction that we can almost “SEE” the walls of the concerts hall and “SEE” the space around each instrument and the distance to the next instrument.

This is much more than we demand in the concert hall. So we are demanding more than the term High Fidelity means!  High Fidelity originally means a faithful reproduction of the sound of the concert hall, and in the average concert hall seat the sound alone did not give us pinpoint accuracy.  What we today demand from our stereo equipment is to have the total experience, which our eyes and ears give us together in the concert hall, but without the 70% information from the eyes!

What can we do to help our ears with “seeing” better, and giving our brain some of the missing information?

We can try placing the microphone at the conductors position. There we have a lot of directional information.  But we get a 180 degree perspective, like a bird eye lens. We also get too much direct sound, and we want to hear the reverb of the hall too.   If we move the microphone away from the orchestra, the perspective becomes more normal, and we get more reverb from the hall. But we start loosing directional information for each step away from the orchestra, so we must choose a compromise somewhere between the conductor podium and the average seat in the hall. Note that we have to use a center seat for the recording, otherwise the balance left to right goes wrong.

Moving a microphone around to find the best sound is very time consuming, so it is seldom done.  We can start using support microphones near some of the instruments, and blend them with the main stereo microphone. The sound travels slowly, only 340 m/s, so just 10 meters distance between the main microphone and the support microphone give us 30 ms delay, which we hear as an echo.

Now we have to consider another problem. Air is not perfect, at say 20 meters distance it absorbs treble more than bass. And the reverb sound is made by reflections from the walls far away.  So close to the orchestra, the microphones hear much more treble, than we hear in a normal seat.

Stereo recording have been made for about 40 years, and many different recording methods have been tried. I find that the best recordings were made in the time from 1957-1968. In this period, the recording engineers did not have so many microphones as today and only 2 or 3 tracks on the tape machines.

Artists often produce their best work, when they are constrained. In this case the limitations of technology meant that both musicians and engineers had to work together to get the right balance from a single stereo microphone. So instead of adjusting the flute level in the mixing console, the conductor had to ask the flute player to play softer or louder.  The engineer too was constrained. He had to find the best place for the single microphone. A place where all aspects of the performance was captured.

But the stereo equipment of this period was not able to reproduce the quality of these recordings.  Only today we can begin to reproduce the 3 dimensional space captured in these old recordings and learn from these old recordings something important about High Fidelity.

A good example is the EMI Classics recording of Carmen on CDS 7 54368 2 stereo. (Only this number, later CD transfer of the original analogue master tape is not that good). In the end of act II you will hear a singer both singing and walking across the stage and then from the back of the stage towards the microphone. The recording was done in 1964.

Ole Lund Christensen