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In what ways similarly measuring cables and equipment can sound different?

Posted by Amine Slimani on October 20, 2010 at 1:17 PM

The idea of writing this article came to me while I was trying to find the right words to explain to head-fier how I felt about the differences between the stock BeyerT1 and the ALO recabled Beyer T1. Since I described the ALO as being smoother sounding than the stock cable, he deduced that the ALO cable was acting as some sort low pass filter. While it is quite explicable, it is far from what I heard. This simple exchange highlighted two things to me: Written communication is obviously tricky in this hobby of ours, and the message intended by the receiver is often not the one received by the reader; also, audio reviewers lack the appropriate vocabulary to describe accurately the music that a system makes. It is far easier to describe the soundsthat to convey the emotions behind.

 

What is said below is pretty obvious, so I apologize in advance for talking about it. But some less experienced members might not have those particular concepts clear in their minds. So I encourage the readers to take the necessary precautions when reading and interpreting reviews, be it mine or other people’swritten text.

 

So let’s move into the less obvious. When I was looking for words to describe the differences between the ALO cable and the stock cable, what came to mind is how lit up specific frequency bands were relative to the others.

 


Let’s start with a simple analogy. Let’s assume you are looking at a room from a window in the outside. Let us also assume that you have different lighting methods. You can either put one big spotlight or two or more (smaller)spotlights.

In both cases you will be able to see most of what is inside. Looking with only one spotlight will cause more difficulties seeing some parts of the room than if we were to use multiple spotlights (but you will still be able to see them). But by concentrating enough, you should be able to see those less lit up objects. It is not the amount of light that is present in the room but rather the way it is spread in the room that makes the most difference. Of course the amount of power and kind of light used in each spotlight will have different the result will be.

 


With that said, let’s move into cables and components that might have similar frequency measurement curves but rather different tonal balances. How is that possible?Is it the fruit of mass hallucinations and placebo effect in the audiophile community or are there other reasons to describe what people are hearing?

If two different components or cables have the same Frequency Response curve, how is it then possible to sound any different in the perceived frequency response by the listener?

 

 

Well the answer is, at least, in two folds:

 

First, most measurements are done in static mode. What it means is that most of what isbeing measured is the amplitude of different frequency values and not how fastthat amplitude can be achieved. In most measurements, you won’t see measurementsof square waves (though Stereophile does it on amps) and how truly “quick” components and cables are. Since most amplifiers and cables measure relatively flat in the frequency band that concerns human hearing, it would be interesting to have more of those square waves measurements. Some people will tell that such tests are irrelevant because no DBT (Double Blind Test) has showed that a person could detect such“anomalies”. Given that most of those studies were conducted by non audiophiles with not so resolving equipment, you get into a circular problem and probably get my point on the subject, which is that, contrary to mainstream beliefs, the faster the components and cables, the less the subjective will be.

Though the way the “speed” is attained is very important. If an amplifiers measures “fast” because it uses heavily negative feedback, it might not sound as good as an amplifier that measures less well on some areas but is using zero negativefeedback. (Those are gross simplifications about general topologies, and I don't intend it as general rules).  

 

The second point, which is related to the first one, is how fast and how lit up specific frequency bands are relative to each other on a cable or a component.

If we assume that instead of the room, we have the frequency spectrum and instead of the light, we have the clarity of the cable or component, you might start understanding where I am going with this.

 

A poor component will have, for example, one big spot light trying to shed some light on the entire frequency spectrum (not an easy job to do). Usually, those cables (or components) will have narrow frequency bands where the signal will sound clearer and cleaner than the other frequency bands. It is not like if the cable will alter the “quantity” of the Bass/Mids/Highs but rather it will change how much effort we have to do to hear them.

That is why you might find yourself “cranking-up” the volume on entry level set-ups to hear all the details you are used to in higher end systems. It is not like the details are not there at all, but you have to make a lot of efforts or raise the volume to hear them.

Meanwhile, those cables and components that act somehow as filters (for the light or sound) will mess with the timing of the information. That is why you might find yourself describing a violin or a piano as fake sounding when the connected equipment measures flat in the frequency domain. Depending on the nature of the component or the cable, those attenuations will lead to distortions that might be perceived as brightness, bloat, bass lightness...while the measured bass/mids/highs didn’t change in the amplitude domain.

 

A better component or cable, staying with the room analogy, will have more spotlights, which incidentally means that its light will be more evenly spread throughout the frequency spectrum. This means, that listening to a higher quality component will call less attention to itself, frequency aberration wise. In some weird way, the more you spend, the less it might impresses you on quick listening sessions.

So by having a better “coverage” of the frequency audio, the better component or cable can provide more subtleties and more distinction between close sounding notes. Also, the level of perceived low level details might increase, thus making the cable or component more capable of drawing a believable soundstage. 

Though, by removing a coloured cable or component and replacing it with a more evenly lit up one, you can throw a system out of balance, simply because the more balanced cable or component won’t compensate for any weakness already present within thesystem.

 


This leads us to talk about system synergy and endless updates cycles some audiophiles suffer from. When setting-up a system, and connecting equipment, as expensive as they might be, without further optimization, the end result can be unpredictable and too often unsatisfying on long term listening.

Let us suppose we are building a system composed only by the following: a “bright”source, a “bass heavy” amp and a “mid-centric” headphone. It is possible to build a grossly balanced (Bass/Mids/Highs) system with those elements, yet it will fail to sound natural, and instruments won’t probably sound like the real thing. When building systems solely (or mainly) on that Bass/Mids/Highs overall balance, the results can be disappointing. Once the “honeymoon” period is over, system weaknesses start to emerge and the cure is to often “upgrade” the equipmentor interconnecting cables. Given that the Bass/Mids/Highs don’t describe the right parameters (due to the lack of proper vocabulary) in the first place, basing one’s decision on it might not lead to the real solution of the problem.

 

A different method would be to improve the “base” of the equipment before upgrading the main components. By “base”, I mean power filtration, power cords, vibration control devices and audio racks. The same DAC, for instance, won’t sound the same depending on the associated accessories. Improving the “base” helps to spread the light more evenly throughout the frequency spectrum. It alsofacilitates equipment matching. Since the “cured” components are more evenly balanced, connecting them together creates less matching “issues”.

 

Once that “base” is done, it is also easier to build a high resolution system that sounds natural. I have read a few times people describe, with great accuracy, how acomponent or a cable has more bass quantity that the other one, and how the highs quality is better on another one. It would be ok if the cables or components were in the same level but it sometimes shows a real lack of resolution, regardless of the price paid for the performance. Those compared elements could have extremely different levels of low level details or tonalaccuracy of instruments, yet it would go unmentioned in those reviews or commentaries.

 

A true high resolution system should mimic the best possible way real life and should let you focus your attention on the music rather than the sounds. A good system shouldn’t call its attention into Bass, Mids or Highs. If it does so, it fails in my opinion. It should, on the other hand, convey, in the best possible way,the sound of instruments and the emotion behind music. If a system constantly draws its attention to the high frequencies, regardless of the recorded material, it is a form of distortion. If a cable or component has great “attack” regardless of what the recording might contain, then it is not transparent. It only means that certain frequency bands were more lit up than the rest.

 

Finally, let us go back to the ALO cable vs. stock cable discussion which pushed me to write this article. In the “light” of what I wrote above, I don’t consider that the ALO cable acts like a low pass filter, as theorized by the head-fier I cited previously. On the contrary, it passes more information, with less distortion. The stock cable seemed to have an emphasis (excessive light) on the mid treble while neglecting (to light asstrongly) other parts of the spectrum. The ALO cable is a more balanced cableand provides better illumination and decreased distortion throughout thespectrum.

The ALO recabled T1 sounded more balanced because it was more evenly lit up than the stock T1, with less distortion and greater resolution. It was also perceived as slightly louder and definitely clearer. The brightness of the stock was due to fake resolution while the clarity of the ALO recabled T1 is due to its superior natural resolution.

 

 

To sum up, this article doesn’t intend to provide some truth about cables or components. It is indented to share how I view things and more importantly, to invite the readers to take the necessary precautions when analyzing (any) reviews.

This article is here to provide a possible explanation on what ways different cables(and equipment) might sound different.

The perceived clarity of the signal varies according many parameters: volume listening levels, colouration of the associated equipment, quality of the recording, instrument being played, time domain performance... That is why whensomeone enters critical mode in A/B comparisons, at a pre-defined volume level,many of those differences might go unnoticed. The reason behind that lack of perceived difference is paradoxically due to the fact that the listener is giving his full attention to the sounds, instead of enjoying and listening tothe music like he would do at other times. Once you go into relaxation mode, some of the differences I describe above (in lighting) might pop-up more easily.

 

To keep this article short, I focused my attention on the “lighting” of the frequency spectrum. It doesn’t mean that it is the only parameter but rather it is one ofthe many ways one can approach the problem.

 


Follow-up 21 Oct. 10:


There are a few points I need to clear up to avoid any confusion:


I am not implying that "poor" cables will have a rolled off frequency or will act as a low pass frequency in the audible range. All the cables I have measured (whether cheap or expensive, shielded or unshielded) did have the same flat frequency response from 20Hz to 20KHz (the audible human range).

The same goes for amplitude and measured loudness: for regular length cables, there will be no loss in the measured signal. At least, I have never come across a cable that reduced by a significant amount (more than 0.1db) the signal.


What I am saying is a little different. Unlike oscilloscopes, we, humans, listen to live music and not static test tones. That is why those static measurements do no tell the whole story, and that is why it is necessary to look for alternative ways to measure things in order to explain the differences in perceived tonal balance and loudness.


Let us make another analogy. Let us assume we have 2 cars A and B that both can reach 120mph. The 2 cars have identical characteristics save for the fact that car A can reach 120mph in 10s and car B can reach it in 20s. If you test both cars at a fixed speed (static test tone) both will be able do maintain it. However, if you put both cars on a track (live music) where we introduce the factor of acceleration, car A will have the upper hand. Driving both cars won't feel the same either and car A will feel more powerful while both of them are limited to 120mph.


What it means is that instead of measuring the frequency response, which we already know that in most cases it will be the same, it will be more interesting to measure square waves, or better, a music signal. Nordost is the first company to my knowledge that started a research study to measure the effect of power cords and vibration control devices. See here: http:/www.nordost.com/downloads/New%20Approaches%20To%20Audio%20Measurement.pdf. While they focused on power cords and vibration control devices, the same tests could be done for interconnects or any other equipment for that matter.


How to extrapolate Nordost's findings with what we hear? That is a very tricky question that I won't venture answering. However, I believe it is one of the first studies that give us a possible explanation for the "contradictions" between Frequency Response measurements and what we hear.


In conclusion, I would say that it is unfortunate that most of the time measurements in the audio world are an end in themselves instead of being a means to an end. A real investigative method implies to look for the right measurement to explain a phenomenon and not simply applying a limited number of restricted measurements to explain everything.

I personally believe that there are a lot less contradictions in the audio world between people's impressions and the reality. Most of the contradictions come from trying to measure the wrong parameter (through false assumptions) in order to explain what we hear.


As always, "If it measures good and sounds bad, -- it is bad. If it sounds good and measures bad, -- you've measured the wrong thing." (Daniel von Recklinghausen)

 


Categories: Cables & Tweaks

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3 Comments

Reply Amine Slimani
5:56 AM on October 21, 2010 
I updated the article with a follow-up on October 21 to include a few missing points.
Reply upstateguy
8:00 PM on October 22, 2010 
Another really good article. But it brings up more questions than answers.

[[ Btw, isn't quoting Nordost on cables a little like quoting McDonald's on Hamburgers? ;-) ]]
Reply jkeny
9:52 PM on November 20, 2010 
Just to give you an example of how far this can be taken - have a look at this thread but don't torture yourself with reading it - the main elements related to the point in this thread are towards the end - essentially a modified Hiface was measured & compared to a $30 Chinese USB SPDIF device & it was declared that it was the same. Worse than this the poster said that there was no difference in the sound as the measurements would show this. Here's the link http://www.diyaudio.com/forums/digital-source/168901-rf-attenuato
rs-jitter-reducers-44.html#post2356081 I leave you to draw your own conclusions but Amine will know how crazy this is.

As Amine's sig says, "If it measures good and sounds bad, -- it is bad. If it sounds good and measures bad, -- you've measured the wrong thing." (Daniel von Recklinghausen)