Bi-wiring and the placebo effect - interesting video

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You underestimate the knowledge of many engineers here.
Some do understand. Others don't. Many people don't understand or else don't accept that FT involves integration so there is some averaging effect for everything it shows. What looks like simple white noise doesn't necessarily sound like a little resistor hiss. White noise can sound like frying or popping. The less frequent the energy release, the louder the noise. What looks like white noise can even be a deterministic signal such as a fast frequency sweep. Most people look at FFTs and assume a spectrum can always be interpreted in a simple way. Not true. The full information was there before phase information is discarded so that only magnitude of average correlation with bin frequencies remains. In that case the averaging is over the acquisition time of the spectrum. Further averaging of spectrums does even more.

In addition, some often neglected information exists in the noise skirts at the base of a spectral line.
 
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Here's a test with and without a bi-wired speaker. Measuring mic at 1m distance, no DSP.
Absolutely nothing changed in the room or the setup, only the wiring.
First wire was connected to the bass speakers, second to mids and tweeter.
There is quite some difference in the 250Hz to 1.5kHz range.
I leave it to the seasoned speaker builders to draw a conclusion. 🙂

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Speaker specs:

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What is the crossover frequency of your speaker?

John
 
Here you go:

Cross.jpg
 
This reminds me that my friend told me not to give away valuable secrets in the forum. I said, yeah, I understand. But, they will ignore anything useful anyway,
How to distinguish a good advice from a nonsense one? Just look how many ‘secrets’ are being offered here by some members.

Before ruining very good cable, I would need a plausible technical explanation how would insulation jacket audibly affect signal at such low source impedance and weak electric fields.
Jacket dielectric constant affecting cable capacitance and changed capacitance reflecting on amplifier behavior? That’s unacceptably bad amplifier.
 
Before ruining very good cable, I would need a plausible technical explanation how would insulation jacket audibly affect signal at such low source impedance and weak electric fields.
It was reported by a plausible source in another thread that speaker cable accidently shorted at the speaker end and driven by a powerful amplifier became a tinny sounding speaker. How? Electrostriction and or magnetostriction seem most probable. The forum member acknowledged the forces calculate out to very small numbers, yet the cables produced audible sound.

I don't know if what was going on with the star-quad cable here was related to its dielectric properties or mechanical damping of small forces. However, the effect of removing the jacket was striking. Its a cheap and easy experiment to do.

I will leave it to someone else to tease out the physics of it.
 
There is a longer history of many tests with different types of cable construction, and different types of speakers (electrostatic, box, etc.). The results were summarized for me by the main investigator.

Regarding headphone cable I also now have something I used to think was the best HP cable I ever heard. It was some prototype cable made for Joe Grado (of the headphone company). The stripped star-quad is so much better, the owner of the very rare Grado prototype cable left it here. Its now worthless.
 
I've listened to a good number of well-known music and the instruments are more articulate, more detailed and most of all the highs are less aggressive.
For example, Van Morrison was not the most pleasurable voice to listen to, violins and saxophones tended to have problems too, and I always wondered if there was something wrong in the chain, a DSP didn't help.
It was definitely a worthwhile experiment.
 
I've listened to a good number of well-known music and the instruments are more articulate, more detailed and most of all the highs are less aggressive.
For example, Van Morrison was not the most pleasurable voice to listen to, violins and saxophones tended to have problems too, and I always wondered if there was something wrong in the chain, a DSP didn't help.
It was definitely a worthwhile experiment.
Yet all you measured was a smallish change in FR? How could that account for the change in sound? After all, if it was just a FR problem then the DSP could have fixed it.

IOW you measured the wrong thing, FR, which can't account for the significant changes you can hear in the sound.

The way I am different from you is I don't have to measure the wrong thing first before going ahead to listen to an experiment. That's one reason I don't post FFT measurements.
 
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You want FR graphs of something that has nothing to do with FR (e.g harshness)?

What if FR shows nothing? Then harshness can't change? If it can change without a FR change then what good does the FFT do? Most likely it just leads you in the wrong direction.
 
My big speakers are not designed for bi-wiring. People I know and trust have done the bi-wiring experiments and I accept their results. Also, in non-bi-wiring experiments I concur with others that well-designed star-quad is one of the very best if not the best of cable geometries.

My personal use of bi-wiring has been with power supplies where I do or don't use a shared ground wire. Makes a big difference there. Why? "Shared Impedance Distortion" on the power rails. PSRR has its limits.

Also, IIRC, I was the first person in this thread to explain the technical reason why bi-wiring is advantageous, not placebo.
 
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