The ultimate cables can/can't - only $80,000

[GUTB]

26 minutes ago, gmgraves said:

 

What, then, pray tell, does Bruce Brisson (of MIT) THINK that a line-level equalizer is for if not to allow the listener "to adjust for challenging room conditions (and/or) equipment changes"? Certainly there are enough equalizers on the market to do that very thing for a tiny fraction of the cost of this $80,000 "cable solution".

 

How about:

 

http://www.musictri.be/Categories/Behringer/Signal-Processors/Equalizers/DEQ2496/p/P0146

 

 for $300

 

or, perhaps:

 

http://www.musictri.be/Categories/Behringer/Signal-Processors/Equalizers/FBQ6200HD/p/P0B3T

 

for $200

 

There are more, from both Behringer and other manufacturers. Given what MIT says this obscenely expensive "speaker cable" actually does, I don't get it!!

 

 

 

Obviously it’s not "just" an equalizer.

[gmgraves]

7 minutes ago, GUTB said:

 

Obviously it’s not "just" an equalizer.

 

No? Then what else could it be? Inquiring minds want to know!

[sdolezalek]

10 minutes ago, GUTB said:

 

Obviously it’s not "just" an equalizer.

Ok, that falls into the "opinion" category.  Substantiation, reasonig, basis for that opinion?

[mansr]

11 minutes ago, GUTB said:

Obviously it’s not "just" an equalizer.

Sure, it's a very expensive equaliser.

[GUTB]

Bruce Brisson is a long-time researcher of audio signal cable mechanics and has a bunch of patents like cable networks, phase shift filtering, noise reduction techniques etc. I suppose he could just be lying about all of that, threw up some technobabble patents in order to defraud his customers — or he’s telling the truth and designs a legitimate product that does in general what MIT says it does.

[mansr]

Most patents are nothing but technobabble.

[sdolezalek]

One of the reasons I wasn't so quick to just dismiss Brisson's claims is that we are increasing learning that out of audible bandwidth effects can have in-bandwidth artifacts.  His quote below goes to that:

Quote

It’s generally assumed that the electrical bandwidth of an audio system should be ten times greater than the audio bandwidth. That is, the electronic components should operate out to at least 200kHz. So, what are the first issues that cause distortion when a cable doesn’t work well within that band of frequencies? Cables suffer from a parasitic series resonance at frequencies below about 1.5kHz and from parallel resonances at higher frequencies, determined by the values of the inductance and capacitance. The cable doesn’t function as an ideal inductor. All audio products act as low-pass filters. Cables without networked terminations function as a lossy low-pass filter because of this parasitic capacitance as well as shunt capacitance. The vector seen at the input terminals of an audio signal-carrying cable should be an inductive vector at all frequencies and at all power levels.

We can correct for the parasitic and shunt capacitance by adding reactive components in the network that will offset these effects.

I don't like the way he starts by saying it is assumed that "the electrical bandwidth of an audio system should be ten times greater than the audio bandwidth."  I would guess a number of folks here might dispute that assumption.  But the rest of his statement at least explains what he thinks is going on.  You might say, "yeah" but there is no way these effects are audible, but I hear a lot of folks saying the same thing about upsampling to DSD512 and benefitting from the use of further out of bandwidth and gentler sloped filters.  

 

If the net result is just a tiny bit of re-equalization of the signal, then we have other cheaper ways of fixing that.  So I'm more curious about his claims with regard to this introducing jitter and noise that he somehow filters out.

 

Further thoughts?

[mansr]

That's nothing but technobabble.

[Ralf11]

dunno re 10x but a supersonic input could overdrive a device

 

- ultra-high bandwidth DOES sound groovey tho

[mansr]

10x is complete overkill. No recordings have anything of value above 50 kHz or so for the simple reason that microphones don't capture it. An amp bandwidth of 100 kHz provides ample margin.

 

To then start talking about cables is absurd. Any half-decent cable works well into the MHz range, at least at lengths likely to be used in a home audio system.

[Ralf11]

can we start a betting pool on how long it takes for the phrase "skin effect" to surface?

[esldude]

3 hours ago, sdolezalek said:

One of the reasons I wasn't so quick to just dismiss Brisson's claims is that we are increasing learning that out of audible bandwidth effects can have in-bandwidth artifacts.  His quote below goes to that:

I don't like the way he starts by saying it is assumed that "the electrical bandwidth of an audio system should be ten times greater than the audio bandwidth."  I would guess a number of folks here might dispute that assumption.  But the rest of his statement at least explains what he thinks is going on.  You might say, "yeah" but there is no way these effects are audible, but I hear a lot of folks saying the same thing about upsampling to DSD512 and benefitting from the use of further out of bandwidth and gentler sloped filters.  

 

If the net result is just a tiny bit of re-equalization of the signal, then we have other cheaper ways of fixing that.  So I'm more curious about his claims with regard to this introducing jitter and noise that he somehow filters out.

 

Further thoughts?

This 10x bandwidth thing comes from a time of analog gear.  If an amplifier has a bandwidth of 0-200,000 hz that means it is -3db down at 200,000 hz and rolls off at 6 db per octave above that (usually).  It will be .1 db down at 20,000 hz and above that frequency the phase begins to change between that point and 200 khz.  So for flat in phase 20 khz response you needed an amp to manage 200 khz - 3db for that to happen.  Or you needed instruments working to 200 khz measuring that over 20 khz without corrupting results.  None of this is directly the issue when digital filtering is involved.  There can be other issues about such digital gear, but the old reason you wanted 10x bandwidth and the digital gear are not exactly relevant to each other. 

 

Like many such ideas, it has a seed of truth while not really telling you what you think it is. And as already mentioned cables have bandwidth well in excess of this so monkeying with them isn't needed for audio.  

 

Now his use of analog jitter is rather re-purposing a digital word for analog thinking to convince customers.  Surely everyone knows what a marketing boon the jitter worry is to the audiophile world.  So Brisson's points are sort of true and yet completely irrelevant to audio.  I don't know if his device has enough capacitance and inductance to create a jitter like oscillation at some frequencies.  If it did, it will sound different, and it isn't improving anything.  

 

As for patents, here is a picture of one of the MIT lower priced digital interconnects.  It is part of the patented networking design (the patent number is right there on it).  You can't quite read it in my picture.  It consists of a conventional nicely shielded 75 ohm coax cable, their nice RCA ends, and the part that makes it one of their patented network designs.  It says AVT network inside. That part is a 1 ohm metal film resistor in series with the center lead.   Now that doesn't exactly impress me. 

 

http://www.mitcables.com/limited-production/audio-interconnects/avt-3-digital-interconnect.html

 

You can read here how it has micro-componentry networks in the RCA housing.  (that would be the one ohm resistor). Quoting from the link above.

 

MIT's patented Digital Terminator Technology—Eliminates jitter-based distortions found in all other cables, delivering natural timbre & precise imaging.

[sdolezalek]

6 minutes ago, esldude said:

As for patents, here is a picture of one of the MIT lower priced digital interconnects.  It is part of the patented networking design (the patent number is right there on it).  You can't quite read it in my picture.  It consists of a conventional nicely shielded 75 ohm coax cable, their nice RCA ends, and the part that makes it one of their patented network designs.  That part is a 1 ohm metal film resistor in series with the center lead.  

 

Thanks Dennis! Love it!  I guess far too many of us are way too eager/willing to believe stuff we just don't understand.  The digital age was supposed to make us all smarter, but while it may have increased the volume of answers by 10X, I think it also increased the volume of questions by 100X, making us feel dummer, not smarter...

[GUTB]

Isn't it common knowledge that higher bandwidth sounds better?

[esldude]

1 minute ago, GUTB said:

Isn't it common knowledge that higher bandwidth sounds better?

Or a common wive's tale.

[wgscott]

If these were Cal Tech cables, I would be more impressed.

[wgscott]

54 minutes ago, esldude said:

Or a common wive's tale.

 

Hene their approval factor.

[gmgraves]

7 hours ago, GUTB said:

Bruce Brisson is a long-time researcher of audio signal cable mechanics and has a bunch of patents like cable networks, phase shift filtering, noise reduction techniques etc. I suppose he could just be lying about all of that, threw up some technobabble patents in order to defraud his customers — or he’s telling the truth and designs a legitimate product that does in general what MIT says it does.

Nobody is saying that those MIT cables don't do anything. What is being said is that since the "box" in the cable is passive, it can't do much. Even MIT says that the box controls lows, miss, and highs, so it is basically an equalizer, but passive, high-level Equalizers use huge capacitances, big inductors, and they can only effect their center frequencies at 6 dB/octave. More poles mean more insertion loss, so the box's output would be severely attenuated from it's input, which I would think would be not too desireable. No matter how you cut it', an active equalizer would be superior, and certainly a lot cheaper!

[mansr]

5 hours ago, esldude said:

This 10x bandwidth thing comes from a time of analog gear.  If an amplifier has a bandwidth of 0-200,000 hz that means it is -3db down at 200,000 hz and rolls off at 6 db per octave above that (usually).  It will be .1 db down at 20,000 hz and above that frequency the phase begins to change between that point and 200 khz.

I challenge anyone to discern a 1 dB drop at 20 kHz. 10x is probably a good rule of thumb for instrumentation. Audio is a different kettle of fish.

[mansr]

1 hour ago, gmgraves said:

Nobody is saying that those MIT cables don't do anything. What is being said is that since the "box" in the cable is passive, it can't do much. Even MIT says that the box controls lows, miss, and highs, so it is basically an equalizer, but passive, high-level Equalizers use huge capacitances, big inductors, and they can only effect their center frequencies at 6 dB/octave. More poles mean more insertion loss, so the box's output would be severely attenuated from it's input, which I would think would be not too desireable. No matter how you cut it', an active equalizer would be superior, and certainly a lot cheaper!

And more importantly, a boxful of components is not a cable.

[esldude]

28 minutes ago, mansr said:

I challenge anyone to discern a 1 dB drop at 20 kHz. 10x is probably a good rule of thumb for instrumentation. Audio is a different kettle of fish.

There are young people who can do that.  They still have hearing to around 20 khz.  With test tones anyway.  Don't know about music.  And even then it will be a small percentage of people. 

 

I think the old idea was one common among audiophiles.  What performance level will be blameless if it is achieved. 20khz no lower than 1/10th db and not having any appreciable phase shift was the idea and for that you need the 200 khz amps.  Hearing it was yes a different kettle of fish.  We don't disagree about that. 

[mansr]

13 minutes ago, esldude said:

There are young people who can do that.  They still have hearing to around 20 khz.  With test tones anyway.  Don't know about music.  And even then it will be a small percentage of people.

Sure, with a 20 kHz tone, you can probably hear a 1 dB drop if you can hear it at all. With music, the content at 20 kHz is already far below the level of lower frequencies, so a small change will not be easily noticed.

 

[mav52]

14 hours ago, gmgraves said:

 

What, then, pray tell, does Bruce Brisson (of MIT) THINK that a line-level equalizer is for if not to allow the listener "to adjust for challenging room conditions (and/or) equipment changes"? Certainly there are enough equalizers on the market to do that very thing for a tiny fraction of the cost of this $80,000 "cable solution".

 

How about:

 

http://www.musictri.be/Categories/Behringer/Signal-Processors/Equalizers/DEQ2496/p/P0146

 

 for $300

 

or, perhaps:

 

http://www.musictri.be/Categories/Behringer/Signal-Processors/Equalizers/FBQ6200HD/p/P0B3T

 

for $200

 

There are more, from both Behringer and other manufacturers. Given what MIT says this obscenely expensive "speaker cable" actually does, I don't get it!!

 

 

Or how about the little tone control from Schiit the $149 Loki. 

[gmgraves]

4 hours ago, mansr said:

And more importantly, a boxful of components is not a cable.

Well, yeah!

[gmgraves]

53 minutes ago, mav52 said:

Or how about the little tone control from Schiit the $149 Loki. 

Not as much control as the Behringer 1/3 octave equalizer for $200, but certainly more than the $80,000 MIT "cable". (Gotta wonder how many of these MIT has sold; and I'd love to see a breakdown on manufacturing costs for those puppies. l'll bet it's less than $5000/pair!).