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Synergistic Research XOT Carbon review and testing.


Ittaku
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As a result of a long discussion on https://www.stereo.net.au/forums/topic/119113-tweaks-vs-science/ 

about the utility of using Synergistic Research's XOT Carbon "Crossover Transducers", @Cafad most generously offered to send me his when I offered to test them as the conclusion from listening was that they made such a big difference that they had to have a measurable effect.

 

Brief background. Here is the company's web page on the device:

https://www.synergisticresearch.com/accessories/speaker/xot-carbon/

 

In short they go on to explain they contain "UEF particles" which are "excited by the EM fields which in turn, the EM fields become balanced by the XOTs and more phase correct information is achieved".

 

Here is a picture of the device below:

IMG_20200824_135258.thumb.jpg.538fc63bfaef17e0a5497094ecaf1353.jpg

 

As you can see there are some very nice gold-plated spade terminals on them. I measured the container and it had a volume of approximately 38ml and combined it weighed exactly 50g on my scales.

 

I went on to measure them passively to see what I could find. Bear in mind I'm no expert with these sorts of things so I just threw whatever I could think at it as the assumption was they were so dramatic they'd have a measurable impact.

 

Their resistance was immeasurably high. My meter has resolution up to 200Mohms maximum. The same terminals across my left and right hands I measured myself at approximately 1Mohms. That means their passive resistance is probably comparable to a brick or a piece of wood.

 

Their inductance was immeasurably low. My meter has resolution down to 1uH.

 

Their capacitance was measurable, but only slightly above that of the terminals in free air which measured 9pF. One of the XOTs measured 46pnF and the other measured 36pF.  I was unsure if this only happened across the terminals so I tested various combinations of the terminals, across the insulators, and the body of them, but they only elicited the capacitance across their terminals. To put these values into perspective, it's about the same amount of capacitance good quality speaker cable has per metre.

 

I was unable to measure any DC or AC voltage out of them passively. I applied a 12V DC battery across the terminals for 5 minutes to see if they would store charge in both directions and then measured them and they were still passive.

 

I applied my cheap oscilloscope over them and was unable to demonstrate they elicited any kind of waveform at rest.

 

At this point I was wondering if the "carbon" in the name meant they were simply a lump of carbon inside, so I looked up the density of carbon which comes to about 2.26g/ml and if the 38ml was full of carbon they should weigh 85g plus the canister weight. I also looked up what the capacitance of carbon is and it's approximately 2.5-3, but of course the amount of capacitance will depend entirely on how it's laid out, though it can be used as a dielectric in a capacitor. At the very least, they are not a solid lump of carbon inside.

 

I then proceeded to test the "transducer" aspect of them by connecting them to an amplifier and running sweeps of 10Hz to 24kHz (I didn't have the facility to try higher). At an equivalent power output from my class D amplifier that should have produced 200W into 4 ohms, and my microphone touching against the XOT canister, I was unable to record any elicited audio of any sort above the background noise. Examining the output from an oscilloscope with various sine waves at different frequencies when connected across the terminals, I was unable to demonstrate any alteration of waveform height or shape, nor the addition of any other frequencies.

 

I then placed it across my speaker terminals and chose the tweeter terminals because these are meant to be a high frequency transducer and proceeded to do measurements of my system with and without them in place. My frequency response sweep, phase, and impulse waveforms all looked within margin of error for that between multiple measurements meaning they were effectively identical. I moved them to the amplifier end instead in case it made a difference compared to the tweeter terminals and repeated the measurements and obtained the same response.

 

I then proceeded to listen to my system with a handful of my select reference tracks with and without them in place, back on the tweeter terminals. I was unable to hear any audible difference between having them in place or not. I saw no point in proceeding to do a blind test as I couldn't tell them apart even unblinded. As many of you know, I suffer from Meniere's disease which has ruined the hearing in one of my ears, so the acuity of my hearing is not what it used to be. For my litmus test, I get my son who's 18 and played violin in a youth orchestra always to do final critical listening with me and brought him in to see what he could hear. I did not tell him what I was changing but he knew I was doing something behind the speaker terminals. I switched them 5 times in and out and he was unable to discern an audible difference.

 

Conclusion: Nicely made shiny object with something giving it a tiny and inconsistent capacitance between the terminals too small to have any measurable or audible impact on audio, probably a lump of coal (hence carbon in the name.) I cannot say it was completely inert given its capacitance, but I believe this is as effective as all other synergistic research products in being effective only through the power of suggestion.

Edited by Ittaku
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I looked at the price.

Is that cheap for snake oil?

Do you get 2 for 1?

Any steak knives?

Its a wonder these type of products are allowed on the market  but they always have been and always will.

To quote WC Fields:

"Its morally reprehencible to give a sucker an even break"

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4 hours ago, Cafad said:

Couldn't hear a difference?

 

Well that is interesting.  

Yes it is Jeff I reckon it speaks volumes. ... of course that would have to be volumes measured by an oscilloscope because obviously the human ear and what it is connected to is not to be trusted, at least that is what I seem to remember reading some where. ... ?

 

cheers,

Terry

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7 hours ago, Cafad said:

Couldn't hear a difference?

Yes, that's what I said. Go figure. Happens to me all the time, with power cords, fuses, usb cables etc... I guess I'm just deaf.

Edited by Ittaku
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15 hours ago, Ittaku said:

but I believe this is as effective as all other synergistic research products in being effective only through the power of suggestion.

Is Power of Suggestion (POS) another audio product?

 

 

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7 hours ago, TerryO said:

because obviously the human ear and what it is connected to is not to be trusted

@TerryO, the human ear really can't be trusted in its own right and even much less in its relationship with the brain where even time is distorted. Any cursory reading of how the ear works will provide you with enough doubt to undermine your faith in acuity of your own hearing. 

 

And then remember that this differs from one person to the next, which for an industry such as the Hi-Fi industry, manufacturing mass produced product for an  amorphous consumer market with no fixed measurement standard produces all sorts of weird and wonderful results.

 

I have been watching a number of presentations by Dr. Ted Venema on youtube.  Much of it is over my head as it is aimed at clinicians in audiology.  But it is fascinating, "the cochlea is an amplifier and like all amplifiers produces distortion..." from a presentation on OTE -oto-acoustic emissions.

 

No the ear cannot be trusted, it is a wonderful organ, highly adapted but from my reading its abilities are as much based on trickery, sleight of hand and adaptive shortcuts brought about by evolutionary necessity, it has to my way of thinking numerous cards up its sleeve and rabbits in its hats and again this differs from person to person. 

 

To trust your ears as the sole arbiter of sound is sheer unadulterated folly.

 

 

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8 hours ago, TerryO said:

Yes it is Jeff I reckon it speaks volumes. ... of course that would have to be volumes measured by an oscilloscope because obviously the human ear and what it is connected to is not to be trusted, at least that is what I seem to remember reading some where. ... ?

 

But I did trust my ears, and your implication that I'm just deaf is suitably noted and acknowledged.

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43 minutes ago, allthumbs said:

@TerryO, the human ear really can't be trusted in its own right and even much less in its relationship with the brain where even time is distorted. Any cursory reading of how the ear works will provide you with enough doubt to undermine your faith in acuity of your own hearing. 

 

And then remember that this differs from one person to the next, which for an industry such as the Hi-Fi industry, manufacturing mass produced product for an  amorphous consumer market with no fixed measurement standard produces all sorts of weird and wonderful results.

 

I have been watching a number of presentations by Dr. Ted Venema on youtube.  Much of it is over my head as it is aimed at clinicians in audiology.  But it is fascinating, "the cochlea is an amplifier and like all amplifiers produces distortion..." from a presentation on OTE -oto-acoustic emissions.

 

No the ear cannot be trusted, it is a wonderful organ, highly adapted but from my reading its abilities are as much based on trickery, sleight of hand and adaptive shortcuts brought about by evolutionary necessity, it has to my way of thinking numerous cards up its sleeve and rabbits in its hats and again this differs from person to person. 

 

To trust your ears as the sole arbiter of sound is sheer unadulterated folly.

 

Sorry allthumbs and Con and Co but do you guys actually read the stuff you write? 
 

To me this hobby is all about enjoying listening to the music I like and hopefully building a system that improves that experience.

Some of you guys have gone off down the rabbit hole needing to understand how the ear or the brain works in relation to what you hear, that is fine by me, what is not cool is when some of you use science as an excuse to rubbish others experiences or their choice in equipment.
I am by nature a practical man who very much believes in science and how it has improved our lives, but I don’t give a flying stuff about what either my ear or my brain might be tricking me into believing I am hearing, because it doesn’t matter. Either it sounds good or it does not. 
 

cheers,

Terry

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Just now, TerryO said:

Sorry allthumbs and Con and Co but do you guys actually read the stuff you write?

Huh? I promised to both measure and audition it. I did both. You're getting hung up on the measurement side.

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3 minutes ago, TerryO said:

Sorry allthumbs and Con and Co but do you guys actually read the stuff you write? 
 

Did you actually read what Con wrote? 

?‍♂️

 

18 hours ago, Ittaku said:

I then proceeded to listen to my system with a handful of my select reference tracks with and without them in place, back on the tweeter terminals. I was unable to hear any audible difference between having them in place or not. I saw no point in proceeding to do a blind test as I couldn't tell them apart even unblinded. As many of you know, I suffer from Meniere's disease which has ruined the hearing in one of my ears, so the acuity of my hearing is not what it used to be. For my litmus test, I get my son who's 18 and played violin in a youth orchestra always to do final critical listening with me and brought him in to see what he could hear. I did not tell him what I was changing but he knew I was doing something behind the speaker terminals. I switched them 5 times in and out and he was unable to discern an audible difference.

 

Edited by sir sanders zingmore
*facepalm*
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2 hours ago, allthumbs said:

Is Power of Suggestion (POS) another audio product?

 

 

Do you buy POS in individual units or do they come in pairs.

Where could I order a set?

Reminds me of "Mandrake the Magician gesturing hypnotically".

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1 hour ago, allthumbs said:

 

To trust your ears as the sole arbiter of sound is sheer unadulterated folly.

 

Yeah... that may be so but I think I'm still going to do it.  Listening is nowhere near as much fun if you doubt everything they tell you.

 

Con, I think the "Carbon" part of the name is actually a reference to the new model, these are just the older 'XOT's" the new model are the "XOT Carbon". 

And unless I miss my guess the carbon only refers to the sheath the tube is wrapped in (since it looks like carbon fibre).  I don't think the word is important in any way except product differentiation between models (and bling of course).

 

When you tried the XOTs out on the amp end was it still only on the tweeter wires or on both? (I don't know if you bi-wire or bi-amp as I'm not familiar with any of your gear)

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It's an interesting article one way or another.

 

With one exception in my view, I think it can be a physiological thing... largely. I have seen this in questioning different people some into this hobby but a fair few that were not.

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Just now, Cafad said:

When you tried the XOTs out on the amp end was it still only on the tweeter wires or on both? (I don't know if you bi-wire or bi-amp as I'm not familiar with any of your gear)

I tried them at both ends as I bi-wire.

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Don’t quote me on this, but I hear people have had some success tying the device to end of a long willow branch and walking it up and down the backyard, in order to detect buried treasure. Try that with an oscilloscope!

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33 minutes ago, Cafad said:

Yeah... that may be so but I think I'm still going to do it.  Listening is nowhere near as much fun if you doubt everything they tell you.

Who said you shouldn't?  If you read my post my conclusion is that you shouldn't trust your ears as the "sole" arbiter of sound.  Maybe I should have added "good" sound but that is neither here nor there.

 

To my way of thinking I wouldn't trust a hi-fi product designer of any component that relied solely on their ears either and I am pretty sure they don't.  Even snake oil producers make the pretence of using science to design their products.

 

I'd daresay that what motivates hifi product developers is designing products that overcome the shortfalls of our hearing, to trick the ears and the brain to provide the ultimate sonic illusion within the limits of physics and proven technology.

 

I'm talking about my own hearing as well Cafad, I am in the same boat as the rest of us.

 

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3 hours ago, allthumbs said:

@TerryO

 

To trust your ears as the sole arbiter of sound is sheer unadulterated folly.

 

 

Absolute rubbish (or folly) the only thing I am interested in is how it sounds to me.

I don't care how it measures or how it sounds to someone else.

The only thing I have for listening is my ears.

Sure when I am building something I measure, test and compare. But when it is finished I DON'T CARE.

Edited by Colin Rutter
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