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Distortion down to -300 dB, what exactly does that mean physically?

Jimbob54

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Why does he feel he needs the BS when his designs measure so well.
Keith

Because then he would have no story. Just some silly coloured marbles in an aluminium brick for the price of a car that offers the buyer nothing audibly different than a £100 black box from the other side of the world.
 

maverickronin

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Just some silly coloured marbles in an aluminium brick for the price of a car

:D

rSaqI78.jpg
 

amirm

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I keep hearing about blind tests' being stressful. Is this something that audio reviewers and high-end industry guys just say?
Blind tests can be stressful if someone is watching over your shoulder. In the case of Rob Watts, no one is looking at him so he can take his time and verify what he thinks he is hearing, he really does. I routinely do this in developing EQ for speakers and headphones. There is no stress involved other than realizing after the fact that you were wrong. :)
 

Cbdb2

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Blind test are stressful if your trying to prove something, especially something thats going to make you money, or something you spent a lot of money on.
 

richard12511

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What they never explain is why that stress magically vanishes when testing level, frequency response, localization, compression…

Lame excuses for avoiding basic controls are rampant in all sorts of quackery, not just audio.

In that case, we need to trick them into thinking they're listening sighted. Has anyone ever done something like that?

I'm thinking something similar to what Penn and Teller did with the Artisinal Water at that fancy restaurant.
 

SIY

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In that case, we need to trick them into thinking they're listening sighted. Has anyone ever done something like that?

I'm thinking something similar to what Penn and Teller did with the Artisinal Water at that fancy restaurant.

Many, many times, yes.
 

restorer-john

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My way to get an idea of the audibility of distortion was to play music at my normal level then start to reduce the level. By the time I have turned it down by 60dB I can just barely hear it. Now I am not listening to distortion artefacts, of course, but what I am doing is listening to sound as loud as the distortion artefacts would be.
Now my judgement is that were this sound level to be playing whilst I was listening to music at my normal level I would be unlikely to hear it - since I can barely hear it on its own.

-60dB (0.1%) THD (H3/4/5 etc) is really easy to hear on a pure tone when toggled on and off. In the middle of music, not so much.
 

Frank Dernie

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I keep hearing about blind tests' being stressful.
The only stressful thing about them is the proof that their own point of view is in error.

Mind you IMO there is a difference between obviously audible, audible but only on some types of sound, audible to a well trained listener using special techniques and inaudible.

As far as I am concerned the last two aren't worth bothering with, for enjoying music.
 

Frank Dernie

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-60dB (0.1%) THD (H3/4/5 etc) is really easy to hear on a pure tone when toggled on and off. In the middle of music, not so much.
Interesting. Not a test I can do on myself and surprising considering how quiet the distortion artefacts are - though that depends the sound level of the test, of course.
 

pma

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-60dB (0.1%) THD (H3/4/5 etc) is really easy to hear on a pure tone when toggled on and off. In the middle of music, not so much.
Are you serious about -60dB H3 to be ”easy to hear” on a pure sine? At what level and frequency? Shall I make a DBT for you? And with music, there is no chance in a DBT.
 

restorer-john

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Are you serious about -60dB H3 to be ”easy to hear” on a pure sine? At what level and frequency? Shall I make a DBT for you?

Don't need to. I've done it plenty of times. It's an obvious broadening of the tone. 1% is easy. 0.1% is harder. I can hear 0.08% on a 1kHz- 3kHz pure tone in a toggle on/toggle off ABX. Done enough 16 trial ABXs with Foobar to satisfy myself. As you know, 0.1% is easy to see on a CRO too, not so easily on a DSO.

In music of course not, that's why I said what I said in my post.

Try it yourself Pavel and report back.
 
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RayDunzl

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This is a wrong equation.
1 bit = 6 dB<- this is a lie


1 = 1
10 = 2
100 = 4
1000 = 8

Bits represent voltage in a digital file

Doubling of value with each new MSB = 6dB

1621667412696.png
 

Geert

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About the Hugo DAC:

As Rob explained, the inter-aural-delay neural network of our brain measures time delays between our ears. It operates at ~4µs for a biological 250kHz sample rate. That's far in excess of Redbook's own 22µs timing. Rob's contention is that a FIR filter akin to our brain's processing power would require 1'000'000 filter taps. That's still beyond current tech. But Hugo's WTA filter already uses 26'368 taps which rely on 16 paralleled 208MHz DSP cores. Hence Chord's refusal to work with commercial chips. Their 150-250 taps are far too low-rent to keep up with the bio DSP of our human brains.

Source http://6moons.com/audioreviews2/chord/2.html

So we need high res audio (high sample rates more specifically) not for the extended frequency response but to get the timing of transients right, which would improve the sense of depth of the stereo image o_O

Any research that confirms we are capable to notice ITD's as accurately as the speed our brain cell membranes operate?
 
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q3cpma

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About the Hugo DAC:

As Rob explained, the inter-aural-delay neural network of our brain measures time delays between our ears. It operates at ~4µs for a biological 250kHz sample rate. That's far in excess of Redbook's own 22µs timing. Rob's contention is that a FIR filter akin to our brain's processing power would require 1'000'000 filter taps. That's still beyond current tech. But Hugo's WTA filter already uses 26'368 taps which rely on 16 paralleled 208MHz DSP cores. Hence Chord's refusal to work with commercial chips. Their 150-250 taps are far too low-rent to keep up with the bio DSP of our human brains.

Source http://6moons.com/audioreviews2/chord/2.html

So we need high res audio (high sample rates more specifically) not for the extended frequency response but to get the timing of transients right, which would improve the sense of depth of the stereo image?

Any research that confirms we are capable to notice ITD's as accurately as the speed our brain cell membranes operate?
https://www.audiosciencereview.com/...ution-of-redbook-16-44-pcm.22102/#post-733457
 
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