TRT Sound Certificate

The TRT Sound certificate is to the "recording chain" what the THX certificate is to the "reproduction chain".

The purpose of the THX certificate (created by George Lucas in 1983) is to ensure that the audio of the film is reproduced exactly as it was conceived in the mixing room.

The purpose of the TRT Sound certificate is to ensure that the sound heard in the mixing room is exactly the same as the sound produced by the performer on stage.

All our recordings have this certificate. They all show the sound of the instruments "as is", without subtracting or adding anything. The result is a sound with unprecedented naturalness.

Truthful Recording Technology

We often receive positive comments talking about the exceptional "naturalness" of the sound of our recordings but, above these favorable comments, what strikes us most is the perplexity shown by some users who do not understand why no other recording offers a sound like this.

Well, the purpose of these lines is to explain the reasons why this happens.

Seen from the outside, outside of the recording industry, it may seem incomprehensible but, understanding what the recording process entails, there are really many reasons why this is so.

Here you have an article that talks about the birth and evolution of stereo recording. The article is written by Bob Shingleton who was director of EMI records during the time of the famous recordings of Herbert von Karajan and Sir Adrian Boult.

The article talks about the formation of two schools of mic placement. The American school and the European school:

"Alan Blumlein and Harvey Fletcher's pioneering work on opposite sides of the Atlantic resulted in two 'schools' of microphone placement developing in the stereo era. The American school, with its roots in Bell Telephone's 'curtain of sound', favoured the multiple microphone approach. By contrast the British/European school, with its roots in the 'Blumlein pair', favoured simpler microphone placement."

These two schools are just two different approaches to trying to solve the same "problem".

What the article does not do, perhaps because it is something that it takes for granted, is to describe what is the "problem" that these two approaches are trying to solve.

What would then be the description of the "problem":

Every time you try to record something, no matter how good the hall is, the microphones seem to capture the worst. Simply the recording never sounds like the original event did. The microphones seem to work like a selective audio microscope picking up and increasing all the defects in the hall.

Why does this happen, what is going on:

The standing waves and the resonances of the hall cause deformations in the audio spectrum that picked up by the microphones are translated into coloration and alteration of the balance of the recorded sound.

What is the solution provided by each one of these schools:

With the European approach, we are simply trying to find a "clean" spot inside the hall. A place where all those standing waves and resonances somehow balance each other to cancel each other out. If we do it successfully, we will get a recording that will benefit from the cleaner sound produced by fewer microphones, but we will never get the "presence" in the sound produced by the American approach.

With the American approach, we are simply planting microphones throughout the scene. We do not have to worry about the sound of each one of those microphones. We just want to make sure we have a lot to choose from. We will treat the sound later on the mixing table. The result will be a recording with a lot of "presence", but we will never obtain the "clean" sound produced by the European approach.

Neither of these two approaches addresses the source of the problem:

In both cases, the same thing happens. Imagine you have been hired to make a recording. You move to the hall where the recording will be made and you mount your equipment in it. The only two things you have control of are: the choice of your equipment and the placement of the microphones ("American" or "European" approach). Working on the acoustics of the hall is out of the question, that is an important job that would take too much time and too many resources.

You can not treat the source of the problem (the acoustics of the hall) but you are expected to get good results anyway. It is not surprising that there are so many different recording techniques both in "American" and "European" schools. Anything is "useful" if it helps to alleviate the effects of the problems caused by the acoustics of the hall.

In addition to talking about the formation of these two schools, the article explains how one of the two has become the standard nowadays:

"In recent years the classical recording landscape has changed completely. Financial pressures and the consequent advent of 'live' concert recordings by orchestra owned record labels mean the more flexible and lower cost American model dominates, to the extent that the geographic labels are now redundant as multi-miking has virtually become standard on both sides of the Atlantic. This has, inevitably, resulted in compromises in sound quality"

There are also other factors that helped things evolved the way they did:

The American approach might not produce a clean sound, but its flexibility allows the engineer to "build the sound" at the mixing table. This may not be useful for classical music, but it is essential when recording "pop".

Here we have an approach that produces a sound with a lot of "presence", which requires less time and less knowledge, which allows for correction of technical and musical problems during post-production after the session and is more economical to implement.

If you had to record all kinds of music (classical and pop), which direction would you take?

The American approach has become the standard throughout the world not for being the one that produces the best sound but because it has proven itself to be the most "practical".

Unfortunately, the establishment of multi-miking (or "American school" as Bob defines it in his article) as a standard recording system does not only harm the sound.

This methodology has other side effects too. The decomposition (capture with multiple close mics) and recomposition (at the mixing table) of the sound results in a final product "different" from that produced by the musicians when making the recording. This negatively influences the perception that musicians have regarding the recording process.

To better understand these problems here is a link to this document "The performer' place in the process and product of recording" published by Professor Amy Blier Carruthers (Royal College of Music, London) during the 2nd Conference of the PSN in 2013.

These two articles (Bob's and Amy's) give us a good picture of the current situation.

Bob's article describes the formation of two schools of mic placement. What he calls "American school" and "European school". Just so that the name is not a problem, we could simply call them "multi-miking" and "simple-miking". Or better yet: "close-miking" and "ambient-miking".

Close-miking implies multi-miking since there will be one or several microphones in each one of the instruments of the ensemble that is being recorded with the intention of capturing the sound of each one of those instruments separately so we can mix them later at the mixing table.

Ambient-miking will involve fewer microphones at a greater distance so that each one of these microphones (or pairs of microphones) can capture the whole ensemble. The balance between instruments on the recording will be what the musicians themselves did since we will not be able to change it at the mixing table.

I personally agree with Bob's description: however it happened, we have reached a point where close-miking has become the standard (in pop and classical)

I also agree with his conclusions: the use of this method is detrimental to the quality of the final product (and here I am referring to classical music which is the genre that I know)

I also agree with Amy's description: under these circumstances, the musicians no longer control neither the color, nor the balance, nor the image, nor the dynamic range. All this is done today at the mixing table, however classical music musicians every day on stage are able to produce music controlling each and every one of these aspects from their own instruments without the help of any "technician".

What I do NOT agree with are the conclusions of Amy's document: Amy seems to have thrown in the towel. At the end of her document she concludes that since recording techniques can not capture these things "as is", what we should do is surrender and accept it. And once we've done that, we will perhaps come up with some fancy new use for this product that is "recorded music" which has nothing to do with the "music that musicians make".

I think we all know, and I mean all the guilds involved: from the listeners, to the musicians, to the technicians, engineers and producers, that ambient-miking, well executed, exceeds in sound quality any other technique in regards to classical music.

The problem is that this "well executed" is not so simple. It is not enough to just place two microphones away from the musicians.

We still have to solve the problem of the hall. And it's not a trivial problem. It is the main problem that has generated all this drift.

No one has tried to address this problem at its root. Instead of solving it, it seems that everyone has tried to dodge it. Even at the time when ambient-miking was used, the philosophy was not "let's fix the hall" but "let's find a place where it sounds good". And this is extremely expensive. It takes a lot more time and knowledge (which translates into production costs). And it is the main reason why we find ourselves in this situation.

So, we have close-miking that produces a sound with "presence" but not "clean". On the other hand we have ambient-miking that produces a "clean" sound but without "presence".

The ideal would be to have a "clean" sound with "presence" but none of these two methodologies can give us something like that.

Ambient-miking produces a "clean" sound, but if the acoustics of the hall are not modified, the result will never be perfect. The placement of the mics, no matter how carefully they are placed, will always be the result of a "minor evil" analysis. The sound is composed of several factors (balance, timbre, dynamics, image). In a regular hall, no placement maximizes the outcome of all these factors. Whatever we do, we will always be capturing defects that will divert the sound of our take from that perfect balance that produces the sensation of "presence".

On the other hand, multi-miking will allow us to capture each instrument separately. We can even capture the different ranges of one single instrument separately. This will allow us to handle each one of these takes independently. The defects of each one of these takes will be different from each other but being independent takes we will be able to do whatever is needed to correct each one of them without affecting the others. This will result in a great sense of "presence" for each and every instrument but we will have destroyed everything else.

What can we do to achieve a "clean" sound with "presence"

Personally I think that the only way to achieve such a result, as far as classical music is concerned, is with the use of ambient-miking, but how will we solve the problem of the lack of "presence"?

The "European" recordings that Bob describes in his article already suffered from these problems. The solution at that time was the use of "spot mics" that were added on post-production with the use of the mixing table. This solution was the beginning of the end. This path, which I think is wrong, was the one that opened the door to the use of close-miking.

The correct way to get this "presence" restored is to solve the original problem we were talking about at the beginning, which is "the acoustics of the hall", but this is something that has never been tried before because it has always been believed to be a utopia.

This utopia is the motor of our project.

In conclusion and answering the original question:

Why is it that no other recording offers a sound like this?

To understand why this happens, you have to understand first how the recording process works. It is important to understand that, no matter which method you use (close-miking or ambient-miking), the sound will be altered from the moment it is picked up by the microphones.

The task of the technicians and engineers is to work on that "altered sound" to try to restore it to its original qualities. The better this work is, the more natural the result will be.

Needless to say, all recordings, each with the means at their disposal, try to offer the best possible sound.

No other recording offers a sound like this, not because they do not want to, but simply because they do not have the methodology to produce it.

Our methodology, Truthful Recording Technology, is the result of a research proyect to develope a recording system capable of capturing the sound of instruments "as is".

When we speak of capturing the sound "as is" we are not only referring to a "clean" sound with "presence". We are also referring to a sound that corresponds absolutely with every aspect (balance, timbre, dynamic, image) of the original (what the musicians did on stage)

These recordings aim to achieve the effect that Bob refers to in his article when he talks about "taking the listener to the music":

"The chapter in Hi-Fi in the Home is titled Music to Listener or Listener to Music? In it John Crabbe argues the point that the role of the recording and reproduction process is to take the listener to the music by providing an aural window into the performance"

Our work is a continuation of the path started by Blumlein whose maximum exponent are the iconic recordings of Kingsway Hall from the years 1960 - 1970 to which Bob refers to in his article:

"The simpler British/European school of microphone placement produced the most realistic and purist sound, as can be heard in Decca and EMI's iconic Kingsway Hall recordings. But these recordings were subtle rather than showy and could sometimes sound thin and unimpressive"

As the article well describes, the problem of these recordings was their lack of "presence".

In the Kingsway Hall recordings, the methodology of the engineers was reduced to looking for the best placement of the mics without modifying the hall.

Our solution is more purist. We placed the microphones first with only one criterion: the image. We then worked the hall to optimize the result of everything else (balance, timbre, dynamics)

The result is a system capable of capturing the very essence of the sound of the instruments without the disadvantages presented by those iconic recordings of the 60s and 70s.

Lets make a comparison between methods so we can see how it all works.

Imagine we have been hired to make a series of recordings (four or five recordings of different chamber music ensembles). The person that hired us wants us to make all these recordings in the same venue and always aiming for the most natural sound possible.

Here is what we would do if we were using close-miking:

- Things we do prior to each recording session:

We place one mic for each instrument. We just need to make sure each mic captures the sound of one instrument as independently as possible from the others.

The mic arrangement will be completely different for each recording session (different number of mics, different distances from the instruments, different places within the stage...)

- Things we do after each recordings session:

We should have been able to record each instrument on a separate track. The recording engineer can now treat the sound of each instrument independently without affecting the others. He will try to use everything that is at his hand (limiter, compressor, expander, gate, eq, etc...) to try to make each one of those instruments sound as "good" as possible. I say "good" because here the engineer has no objective way to check if the resulting sound is more or less "true". All he can do is aim for what he subjectively thinks sounds more natural.

Once he has fixed all the tracks he will go ahead and mix them at the mixing table. He will adjust the level and pan (left and right) each instrument separately until he gets a stereo sound and a balance that, again, he subjectively thinks sounds "good".

Now, we could stop at this point, or we could send this final mix to the mastering engineer for further processing. The mastering engineer will treat the sound of this stereo file using everything that is at his hand to try to achieve what he subjectively thinks sounds even better.

Here is what we would do if we were using ambient-miking:

- Things we do prior to each recording session:

We look for a good sounding spot to place our mics. We try several positions that we think are reasonable and listen to figure out which one sounds best.

We should do this for every different ensemble because we might end up using different spots for different ensembles.

- Things we do after each recording session:

We should have been able to capture all the instruments in one stereo track. We cannot treat instruments separately. Anything we do will have to be applied to all instruments at once. The recording engineer will now do whatever it takes to try to make this stereo track sound as "good" as possible. Again, I say "good" because it is still a subjective matter. Different engineers would probably end up at different places.

After this, we could stop here or we could send this files to the mastering engineer so he can again treat the sound just like he did in the previous scenario.

Here is what we would do if we were using Truthful Recording Technology:

- Things we do prior to ANY recording session:

We choose a spot to place our mics in but, at this point, the only thing we should be concern with is image (as if we were placing a video camera). This will be the place of the mics for every recording.

Once we have our mics in place we run tests to determine what we can do to the acoustics of the hall to try to improve the sound at the pick up point. The more resources and time we have the better the results will be but even with endless resources and time we will never completely fix everything. What ever we end up with will be the hall configuration we will use for every recording.

Then we work on a filter that will compensate for those things that could not be fixed on the physical hall. We will use this filter exactly the same way in all our recordings (this filter is what we call the "calibration").

- Things we do prior to each recording session:

We do not have to do anything.

- Things we do after each recording session:

Nothing subjective, just process the recording with the calibration filter.

Cookies help us deliver our services. By using our services, you agree to our use of cookies.  Learn more