[bfreedma]

General comment:

Many people believe they can conquer various forms of human bias. Those who feel strongly about this should check their sighted testing results against their results from participating in a reasonably well constructed DBT to see how controlled testing results align.

 

[DaveStarWalker]

I had tons of problems with my NAD CD player. First a full bridge rectifier blew and was repaired (now 4 times "bigger" just in case). Then soon after the motor that operates the disc tray blew and was replaced. NAD is garbage these days, but I am a NAD fan so it is what it is... The NAD amp measures one of the worst amps but apparently the problems are inaudible and I am very satisfied with the performance. It is just shame that the stupid amp can't send digital sources to "ZONE 2" which I use to drive my headphone adapter/cross-feeder.

I was talking sound wise.

Sorry about all these problems.

It sucks.

 

[bigshot]

How about this. What If:
1) Manufactures aren't properly rating these specs? who does the rating? is there any verification from an exempt third-party auditor?
2) They're deliberately delivering below specs items because most of us wouldn't notice anyway and it's cheaper?
3) Cheap chips could cause weird quantization errors, or other artifacts in its decoding?
4) The actual analogue electric current generated was garbled from it's original information packet from the digital data it received? yes, it can read vanilla specs, alright, but does that prove it emits the same equivalent specs in analog form with all of its integrity? is there any actual proof to this, testing, verification, auditing?

If a player or DAC wasn't performing to digital specs, you would know about it. There are people who do third party verification. Here as an example is a very good set of measurements of the iPhone that made quite a stir when it was released...

https://www.kenrockwell.com/apple/iphone-5/audio-quality.htm

It's no more expensive to produce a chip that performs to spec and avoids quantization errors. The cost of perfect sounding DAC chips is well under $10 apiece many are under $5. The way chips are manufactured, cost isn't an issue.

I think all these things could account for a DAC behaving differently. And each chip is designed differently, they are not all identical. Each brand has their proprietary technology, from the machines they use to build things to the assembly part. A factory might have better quality control than another. What makes every model of every brand apparently homogenic is that they all "deliver the necessary specs" ie: they can read 16/44.1 or sometimes higher. But is that really reliable? It's just numbers... it doesn't measure the quality of the output signal that was translated.

DAC chips are made by a small handful of companies in massive quantities and are off the shelf components. Each manufacturer makes a range of chips designed for specific applications. The same chip might be used in a wide variety of brands and models. Every one I've ever seen has been designed and manufactured to meet spec. I can't think of any application for a DAC that doesn't perform to spec. In fact, I'm hard pressed to think of a way that a chip could even decode a digital file format incorrectly without resulting in massive noise or distortion. Digital is an "all or nothing" thing. It isn't like analog where errors can be subtle. I know audiophools go on and on about the differences between Sabre, Wolfson and Apple branded DAC chips, but I have components with all three of those and I've compared them and they all sound the same. Chalk it up to brand bias.

The only way a consumer DAC could possibly sound different is if the analog components are faulty. You hear people talking about op amps a lot. But even cheap DVD players have clean enough analog output to be audibly transparent. They may not be clean enough for studio work where levels can be boosted a lot, but for playing back commercial music at a normalized line level, they are fine.

I would love to find a commercial DAC, DAP or disc player that isn't audibly transparent. I compare every piece of gear I buy and they all sound the same. I've asked here for about ten years for someone to provide me an example of a consumer player that sounds clearly different in careful listening test comparison. No one has ever been able to provide me an example, except for obsolete NOS DACs from the pre-1985 era.

If you are buying something to play digital audio, you should consider features and build quality, not the sound. All of them should sound exactly the same. If one doesn't sound the same, it's defective by either manufacture or design. That is uncommon enough that I've never heard of an example.

It seems this is because digital is actually so clean, true, perfect, sterile; a 100/100 copy. So it's about what digital is lacking: defects. The same with transistor vs valve/tube amps: there's some harmonic distortion added and we like it. Humans as we are, we actually like (controlled) defects. Take the "lo-fi" genre, for example. Adding vinyl pops and clicks and hum to songs. Not always do we crave for perfection; there is beauty in imperfection.

There are DSPs that emulate vinyl surface noise and euphonic distortion. The nice thing about them is that they are adjustable. You can dial in exactly the amount of error you want. You aren't locked in to distortion hard wired into a tube amp, or random surface noise on a record album.

With any kind of coloration, it's best to start from a place of high fidelity. Clean and accurate. Then you can use signal processing to color it to taste, like adding salt and pepper to a steak.

 

[bigshot]

So as you can see, while bias is real, the bias for trying to disprove something is even worse, as it can cause denial of evident effects; I think it's all about being honest with yourself at all times. If you're a cunning man with a big ego, I'd definitely take into account a strong bias from that person; but we all know ourselves, and as long as you're earnest in your efforts and being sincere with yourself, ie: it does not matter that I have either 'wasted money' or 'found the holy grail', the important is the truth above all else, all things must pass, then I think you can get to good results which might not please a scientific community, but are enough to please oneself.

All humans are subject to bias. It doesn't matter how hard you try to be objective, subconscious bias is subconscious and you can't control it. It doesn't matter if your bias is in favor of something or against it. It's the same thing. It's a waste of time to try to eliminate bias by sheer force of will. You're only fooling yourself.

The controls placed on listening tests are designed to minimize bias and perceptual error. They are very effective at doing that. If you choose to not apply those controls, it's fair for us to assume that the results of your comparison have been tainted and may not be at all accurate. That kind of sloppy comparison is fine for you. If it really doesn't matter to you, and you want to just go on first impressions yourself, that's cool. No one is trying to stop you. But if you try to share that kind of comparison with someone else as a recommendation or fact, don't be surprised if someone calls you on it and tells you that you're spouting bologna.

I disagree; a .FLAC and .MP3 sounds different; even if something is "outside audible frequencies"*, it is still there; resonating in the room and in your head.

Case in point... Bologna.

Once you know the rules, you will be expected to play by them.

 

[cirrus101]

Then you can use signal processing to color it to taste

Yeah. But, it's fake.

I've asked here for about ten years for someone to provide me an example of a consumer player that sounds clearly different

About every device I've used my whole life sounds different from one another. I cannot believe your statement. Just pick any two smartphones, different models, different brands. Or compare it a computer with onboard motherboard sound. Compare old PCs with new PCs. Compare a PC with a dedicated soundcard on. Mp3 players - chinese generic brands sold on the streets and bazars vs big brands (Sony, Panasonic, etc.). List goes on and on. Every one of these offers a different experience, and I'm not talking of its tactile feel. Maybe its not the DAC used per se, but the combination of whatever hardware is employed creates obvious differences.

All humans are subject to bias.

I think your bias is that everything sounds the same. You firmly believe that, because Science. So everything will sound the same.

Case in point... Bologna.

Are you denying that a lossless file contains more frequencies than a lossy one like the mp3?

That's very unscientific. Any simple spectrogram like the one I've posted will reveal that.

Whether those frequencies and their relation to our perception are important or not, that's another issue. But they are there and they do exist and they are part of what exists in the natural world before they were chopped off by compression. Period.

And even your friend of the article you've linked above states the following:

I did spend several hours A/Bing an iPod Touch 4G with 160 kbps AAC VBR files against the original CDs, I wasn't able to hear any difference at all as monitored with a STAX SRM-T1 amplifier and STAX SR-007 MK II electrostatic headphones. (MP3 files sound much worse at the same data rates, I'm not talking about them.)

Mind that parenthesis over there. I hope you like bologna, 'cause I'm giving it back to you.

 

[DaveStarWalker]

"All humans are subject to bias." = well said.

To meditate...

 

[DaveStarWalker]

A very good training = mp3 128 vs 16/24 wav. Blind test. ....

Maybe more relevant than the different masters of a same song.

But far more difficult. Believe me.

I have tried that, years ago (about 20 years ago...) : I wasn't able to tell certainly the differences.

By the way, these differences (degradations) are really... real, spectrogramm wise for instance... This is documented.

Conclusion ? You need to be trained for that kind of (very difficult) excercice.

What do you think about this proposition ?...

No one here is motivated by the challenge ?

 

[chef8489]

Yeah. But, it's fake.


About every device I've used my whole life sounds different from one another. I cannot believe your statement. Just pick any two smartphones, different models, different brands. Or compare it a computer with onboard motherboard sound. Compare old PCs with new PCs. Compare a PC with a dedicated soundcard on. Mp3 players - chinese generic brands sold on the streets and bazars vs big brands (Sony, Panasonic, etc.). List goes on and on. Every one of these offers a different experience, and I'm not talking of its tactile feel. Maybe its not the DAC used per se, but the combination of whatever hardware is employed creates obvious differences.


I think your bias is that everything sounds the same. You firmly believe that, because Science. So everything will sound the same.

Are you denying that a lossless file contains more frequencies than a lossy one like the mp3?

That's very unscientific. Any simple spectrogram like the one I've posted will reveal that.

Whether those frequencies and their relation to our perception are important or not, that's another issue. But they are there and they do exist and they are part of what exists in the natural world before they were chopped off by compression. Period.

And even your friend of the article you've linked above states the following:

I did spend several hours A/Bing an iPod Touch 4G with 160 kbps AAC VBR files against the original CDs, I wasn't able to hear any difference at all as monitored with a STAX SRM-T1 amplifier and STAX SR-007 MK II electrostatic headphones. (MP3 files sound much worse at the same data rates, I'm not talking about them.)

Mind that parenthesis over there. I hope you like bologna, 'cause I'm giving it back to you.

Thing is would all the equipment actually sound different in a proper double blind test?

Some equipment, yes and some no. Engineers design equipment to sound different from one generation to another. While the dac chip might be the same, other things after it can have an impact on how the device sounds.

As far as flac and 256 aac vbr lossy. Again double blind testing and a rate of 95% or higher needs to be achieved to prove that you can tell a difference.

 

[bigshot]

About every device I've used my whole life sounds different from one another.

Did you compare using multiple averaged level matched, direct A/B switched blind tests? If not, I am going to tell you that your subjective comparisons are meaningless because they're likely to error due to bias and perceptual error. There's no reason to believe that DAC chips sound different than one another. They're designed to be audibly transparent. The only differences are in function and performance beyond the range of human hearing.

Repeating... Once you know the rules, you will be expected to play by them.

A few quick notes...

• A PC with grounding issues doesn't mean that the DAC chip inside it isn't audibly transparent. A $10 POC incorrectly designed and manufactured player bought in a Chinese bazaar isn't what I'm talking about either. I'm talking about consumer home audio equipment available right now on Amazon. (NOS DACs excluded.)

• I am subject to bias just like everyone else. I don't deny it. I make an effort to apply controls to my comparisons to minimize it. I don't go purely by my subjective reactions.

• "Inaudible frequencies" means inaudible. Inaudible frequencies don't have a sound by definition. If you can't hear a frequency, there is no reason to believe it has any impact on the perceived sound quality of commercially recorded music.

• With VBR on, AAC 160 is allowed to assign more data to sections of the music that are harder to decode. With VBR on, it is perfectly possible for AAC to be audibly transparent at lower data rates. It's transparent with most sound samples at 192 CBR.

Dave can get by with spouting bologna because he's clearly oblivious and not terribly connected to anything anyone else says to him. (I'm saying that as nicely as I can.) You aren't like that. If you ignore facts and use logical fallacies to make your point, you're doing it deliberately to justify a false argument. I can just dismiss Dave with a wave of the hand, but you asked me to engage with you and I've spent time and energy doing that. I'm going to hold you to a higher standard. Consider this a shot across your bow.

 

[DaveStarWalker]

Did you compare using multiple averaged level matched, direct A/B switched blind tests? If not, I am going to tell you that your subjective comparisons are meaningless because they're likely to error due to bias and perceptual error. There's no reason to believe that DAC chips sound different than one another. They're designed to be audibly transparent. The only differences are in function and performance beyond the range of human hearing. And "inaudible" means inaudible. Inaudible frequencies don't have a sound by definition.

Repeating... Once you know the rules, you will be expected to play by them. Dave can get by because he's oblivious and not terribly connected to anything anyone else says to him. (I'm saying that as nicely as I can.) You aren't like that. If you ignore facts and use logical fallacies, you're doing it deliberately to justify a false argument. I can just dismiss Dave with a wave of the hand, but you asked me to engage with you and I've spent time and energy doing that. I'm going to hold you to a higher standard. Consider this a shot across your bow.

Sorry pal,

It is precisely because I am very connected with so many (and different) people that I have been able to do so many tests and experiments.

It's important not to be self-centered.

I am not a subjectivist or an objectivist person. This is a silly duality. No relevant at all.

But I am a pragmatic and empirist person. For this hobby.

And repeat : real science does nothing with this hobby, because this is... a hobby.

If you want to deal with real science, then, get some money, time, and work out your methods.

Pleasure is not ever an option too = bias.

 

[bigshot]

Some equipment, yes and some no. Engineers design equipment to sound different from one generation to another. While the dac chip might be the same, other things after it can have an impact on how the device sounds.

Why would a manufacturer be motivated to produce a piece of gear that doesn't perform to spec? Do you have any specific examples of this, or are you just assuming this is the case. I've compared a lot of equipment and I can't find any electronics that aren't audibly transparent. Transducers, yes of course. But not DACs, DAPs, amps or players (with the stated exception of obsolete NOS DACs, and manufacturing errors.)

 

[bigshot]

This forum is about science being applied to improve the performance of home audio equipment. There are a dozen forums in the rest of head-fi for subjectivism and casual impressions. I'd suggest if you want to engage in that, you would be much more on-topic in one of those forums.

(not speaking to chef here. speaking to the oblivious one.)

 

[DaveStarWalker]

Why would a manufacturer be motivated to produce a piece of gear that doesn't perform to spec? Do you have any specific examples of this, or are you just assuming this is the case. I've compared a lot of equipment and I can't find any electronics that aren't audibly transparent. Transducers, yes of course. But not DACs, DAPs, amps or players (with the stated exception of obsolete NOS DACs, and manufacturing errors.)

What a statement!

Compared how?

 

[bigshot]

nope. not for you. sorry. g'bye.

 

[chef8489]

Why would a manufacturer be motivated to produce a piece of gear that doesn't perform to spec? Do you have any specific examples of this, or are you just assuming this is the case. I've compared a lot of equipment and I can't find any electronics that aren't audibly transparent. Transducers, yes of course. But not DACs, DAPs, amps or players (with the stated exception of obsolete NOS DACs, and manufacturing errors.)

Daps and some amps are not designed to be transparent in sound. Many manufacturers have a house sound that they tailor their amps and daps towards while others do try to to obtain transparency in audio.