Sound Quality Vs. Measurements

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I guess you're talking about the loudness wars ... I don't worry about anything much from the last 15 years or so, the musical content is not my cup of tea really ...

Plenty of sites out there that have lists of good and bad, just have to work through the Google results ...

All time baddie is the Iggy Pop remastered "Raw Power" I believe - great square wave test signals ...!!

Nor is it mine, Frank, but then again, that would inlude Enya, Loreena McKennit, most of Enigma, and so forth, and those ARE my cups of coffee (I drink tea only when sick in bed, meaning never).

But, I almost wet myself in the pants when I discovered the complete works of Eric Burdon & The Animals carried over to the CD format, I would suggest by an avid fan, judging from how the job has been done. Ditto, for Waldo de los Rios, and a slew of others.
 
I'm happy with CD - that's all I've used for 25 years, because for that period I always knew what it could deliver - I was always able to look past the usual crappy sound in demos and showrooms ...

What is disturbing is the seeming going backward of vinyl - the examples in the recent hifi show in Sydney were nearly all very paltry ...
 
The search for perfection, as is any absolute, is doomed from the start.

There's the issue, assuming 'impossible to be perfect' equates to 'impossible to be convincing'. At the same time others are posting solid evidence for the gaps in our hearing which ironically provide solid evidence that perfect reproduction isn't a requirement.
 
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CD is just about OK . 1972 BBC/Nippon Nicam was and is better .

CD destroyed record shops and a whole community . Nothing in life has done that so successfully . Drunkenness never destroyed Gin . Death never destroyed motorcycles . Impracticality never destroyed sailing ships . CD very nearly destroyed the hi fi industry . It has relegated a quirky but honourable profession to just quirky .
 
Nor is it mine, Frank, but then again, that would inlude Enya, Loreena McKennit, most of Enigma, and so forth, and those ARE my cups of coffee (I drink tea only when sick in bed, meaning never).
Yes, there are always exceptions - I can name Karma County, Olana, from Oz, as a personal favourite ...

But, I almost wet myself in the pants when I discovered the complete works of Eric Burdon & The Animals carried over to the CD format, I would suggest by an avid fan, judging from how the job has been done.
Now you're talkin' ... :cheers: !!
 
CD is just about OK . 1972 BBC/Nippon Nicam was and is better .

CD destroyed record shops and a whole community . Nothing in life has done that so successfully . Drunkenness never destroyed Gin . Death never destroyed motorcycles . Impracticality never destroyed sailing ships . CD very nearly destroyed the hi fi industry . It has relegated a quirky but honourable profession to just quirky .
Should I invite you to our next, Greek style, CD trashing party ...? :D
 
Do you actually believe that the end section is 'clean' audio mixed in with the video clip? If so, then that 'pure' audio is some of the poorest ever done!

Cameras have AGC, they constantly adjust the volume to suit, and there are numerous videos on the net where there appears to be no or very little "variation in music", with movement. I have done videos in a similar, relatively primitive way, and I hear exactly how that video comes across!

Hmmm, no-one has commented on what I'm after, I still need to do some close examination of the waveform to see if I can identify the characteristics that my ears are noticing ...
imagine overture 1812 on lp with no loudness correction..
maybe during the canon explosions would turntable cartridge fly off the disk:D
 
Should I invite you to our next, Greek style, CD trashing party ...? :D

Not really . If the Meridian was the first ever CD player I had tried and some later releases I would have said almost up to the hype . Slightly wicked to con the public into finishing the development and paying it's costs . Almost like the banking crisis these guys knew it was happening . How cynical to say " Perfect sound that lasts forever " . Ringo Star was asked if he was the best drummer in the world ? He said " I am not even the best drummer in the Beatles " . That's more like it .

We use CD's to frighten the crows in our gardens . Crows are said to be intelligent, evil meets evil ? Hated in England as they eat people after the Black death . It's their job I beleive ? The crow is a great symbol of my love of CD .

What I disliked was people switching off any interest they had in hi fi . Bought a computer and sailed off into the blue yonder . They probably disliked CD more than me , they voted with their cheque books . Time was when a hi fi was the 1/3 rd most expensive purchase ( house , car , hi fi ) . Now it is strictly for the birds .

We in some ways have a lost generation of hi fi people . Young people buy guitars . Mostly they don't care about hi fi much . They would if we came out of our ivory towers . Jim Marshall didn't loose them , although for a while it seemed so .
 
There's the issue, assuming 'impossible to be perfect' equates to 'impossible to be convincing'. At the same time others are posting solid evidence for the gaps in our hearing which ironically provide solid evidence that perfect reproduction isn't a requirement.

To be convincing is hardly impossible. For example, I believe my Karan Acoustics KA-i180 integrated amp (180/250W 8/4 Ohms) is very convincing in most respects, ditto for my H/K Citation 24 power amp (100W/8 Ohms, current capability > 560W/2 Ohms) are very convincing performers. If the source material is good, it will sound it; if not, it will be ruthlessly shown for what it is.

As for gaps in hearing, there's nothing I can do about my hearing, it is what it is, period, all I can do is wash my ears regularly and use the cotton swabs, all of which I do every morning. Please no comments on swabs destroying ear drums and such, long before you destroy them you will be screaming in pain. I plumb hate urban legends.

A good friend, working for Bosch in Stuttgart, informed me that the stunning braking my Chevy Cruze has is in fact extra ECU controle over the servo; I replied I didn't care wghat the hell it was, I just love the way that thing breaks.

So it is with music - I really don't give a damn what was necessary to do to make a recording great, I'm paying money for somebody to deal with that as that somebody's job. I honestly don't care what the measurements say about a sound I happen to like a lot, I have been exposed far too many times to devices with terrific specs and measurements which I would never take home, and vice versa, devices playing good music when their specs say they are nothing special and their topology says they have no right to play so well.

In fact, some terrific specs scare the hell out of me. For example, when a power amp is specified with a THD of say 0.001% at full blast - I immediately start wondering whether its global NFB is 60, 80 or more dB. Mind you, I have heard a few amps of that kind which did sound really good, but I have also heard many more amps with lower global NFB and much poorer specs which sounded great as well, but few such amps which didn't sound good.

But that's just me, everybody has their own philosophy.
 
Heavily compressed material replayed correctly is extremely aggressive sounding
for once we agree. some time ago foobar was on 'random' mode and it played a Judas Priest song from Painkiller. it was the first time I ever listened to that album on my current system. I know it by heart since I was a kid. but for the first time, the drums (and, unfortunetely, not only) sounded like modulated white noise. I stood there in awe. how come I did not hear it before with the previous systems? it sounded very different then. if someone told me 15 years ago something like that I would've called it snobbery but it now simply sounded unlistenable, not because of the music, but because of the sound.

I have a hunch no physical contact is not CD's best feature . Just think if USB sticks have been available . CD would never have happened . CD is a throw back to 1888 . Apparently pressing the disc was still No 1 priority when invented .
in all honesty, I have no idea what you're getting at.

Squarewaves from CD stop at about 1 kHz . The Fourier series needs about the 19 th harmonic in the sequence to be square . ( 44.1 /2 ) / 19 . Such a wave looks like an amp with mild ringing . Slew rates ??????? Where , when , how ? To restate my case . Slew rates matter . It is simple current to drive the VAS . There is no music that demands it . If it were not so tweeters would last minutes .
first. you said it yourself that slew-rate is not necessary because it exists in music. how come you also used the slew-rate (more below) of the signal present at the input as an argument for the fact that CD is wrong?

second. can you explain the "44.1 / 2" thing? a perfect (in the mathematical sense) step requires infinite bandwidth. that waveform looks like an amp with ringing because of the Gibbs phenomenon. had you seen no Gibbs, it would be really weird and definitely abnormal. a square wave can't look like a square wave (given you zoom in enough) if you band-limit it. you see that ringing because a perfect step would need infinite bandwidth. and because (as far as current science goes) human hearing does not require infinite bandwidth and RedBok is based on that.

third. with CD you can have slew rates exceeding what is naively suggested by the inter-sample delay. actually, ~3 times larger with RedBook. incredible as it may seem, with properly implemented digital you can actually have all the slew rate that a perfect (again, in the mathematical sense) full scale 20kHz sine needs. it all depends on the implementation. maybe you don't believe me, I'm attaching a screen shot of a generated 20kHz wave in CoolEdit. look at the green squares: those are the sample values. nowhere near sine, innit? in fact it's "oh my, what is that rubbish!". then look at the continuous line. I'll be... a sine! how do you explain that? sinc interpolation, that's what you're looking at.

now... if you tell me that there are psychoacoustic reasons why a LPF @20k is not enough, you do have a case. if you tell me that the reconstruction filters are not always perfect, you do have a case. if you tell me that dither can be a bad thing if done uwisely, you do have a case. but that's totally different from your arguments above.

it's incredible the amount of times we can go round and round and round in circles with this.

of course, all the above is accepting that we don't move within the paradigm of "I still believe it", because, if that's so, we could as well just close the whole forum.
 

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Some people need to watch this: https://www.xiph.org/video/vid2.shtml

Can anyone point to any reputable experiment that shows that CD is anything less than transparent? I can point to an AES paper that says it is transparent:

Claims both published and anecdotal are regularly made for audibly superior sound quality for two-channel audio encoded with longer word lengths and/or at higher sampling rates than the 16-bit/44.1-kHz CD standard. The authors report on a series of double-blind tests comparing the analog output of high-resolution players playing high-resolution recordings with the same signal passed through a 16-bit/44.1-kHz “bottleneck.” The tests were conducted for over a year using different systems and a variety of subjects. The systems included expensive professional monitors and one high-end system with electrostatic loudspeakers and expensive components and cables. The subjects included professional recording engineers, students in a university recording program, and dedicated audiophiles. The test results show that the CD-quality A/D/A loop was undetectable at normal-to-loud listening levels, by any of the subjects, on any of the playback systems. The noise of the CD-quality loop was audible only at very elevated levels.

https://secure.aes.org/forum/pubs/journal/?ID=2
 
In fact, some terrific specs scare the hell out of me. For example, when a power amp is specified with a THD of say 0.001% at full blast - I immediately start wondering whether its global NFB is 60, 80 or more dB
If I was asked to assess in a couple of minutes how good a power amp was I would immediately put on a CD of high energy rock with very dominant, clear cymbal content, and wind up the wick, all the way. This would tell me straightaway whether it had decent chops, and was worth worrying about - only recently have I seen standard amps do a half decent job here ...
 
I have a hunch no physical contact is not CD's best feature . Just think if USB sticks have been available . CD would never have happened . CD is a throw back to 1888 . Apparently pressing the disc was still No 1 priority when invented . Making Cassettes was a fools game. Expensive and less than excellent . They were not going to repeat that mistake . CD , BS that lasts for ever . Even the last bit was lies .
:yikes:
do you remember first flash mp3 players ? thomson, sony, panasonic? 64 and 128MB ! types, costed arm and leg!

today you will receive 512MB usb disk as free advertising gift.....
 
:yikes:
do you remember first flash mp3 players ? thomson, sony, panasonic? 64 and 128MB ! types, costed arm and leg!

today you will receive 512MB usb disk as free advertising gift.....

Right, but I don't see where's the surprise?

We've been seeing the same effect in PCs forever. Memories start off as expensive and drop to rock bottom prices, and that's when the industry invents a different type of memory to get its profits back up again.

Old hat.
 
CD is just about OK . 1972 BBC/Nippon Nicam was and is better
Why do you say that? NICAM was only 32 ksps, so 15kHz is about the absolute upper limit
It uses a 14 bit 10+4 structure, so in any data block you only get 10 bits of resolution. This is marginal for low level detail in a frequency band far from a strong signal which is at a frequency where the ear is insensitive
 
Mr Push Pull .

44.1 kHz is the sampling frequency . Divide by 2 to get Nyquist theoretical maximum frequency . 22.05 kHz . Leap of faith now . The Open University taught that the 19 th harmonic ( 1/19 F 19 ) is required to get a reasonable square wave . The series is infinite as we know so I am being generous to say we might get a 1 kHz square wave out of a CD . Seeing as 10 kHz square-waves were routinely possible from transistor amps circa 1964 it is interesting that digital allowed us to think it unimportant .

I agree rise time can be very good on CD . However for various reasons we can not record any signal we want even within the supposed bandwidth . To say we don't reduce rise time significantly is correct and is the saving grace of CD . Off set this will typical energy levels at 20 kHz to say in reality it is not a big problem .

My objection to slew rates is that music does not demand it . Other poorly explained mechanisms are working . They are far from unimportant . As Douglas Self said these things show up in other measurements when less than ideal . One commenter said both SACD and MC pick up have signals that require high slew rates . I totally doubt that . The fact the VAS needs current is fine . Call it current starvation and I might start to beleive it . I remember about a week going by and a great agreement on slew rates was reached . I sat back and thought and who really said why . Lets be clear I design as all do . I am jut not comfortable that we say it is true because we say so . I will throw in a suggestion . Make an amp with compromised slew rate . Listen and find it sounds constricted . Input filter it . Does it suddenly sound great allowing for lost sparkle . I bet it doesn't .

1888 . Berliner found a cheap way to quickly make copies of recorded music . People may not realize that this fact alone is the big deal for mass production . CD needed that speed of production . Old dogs , new tricks ?
 
Why do you say that? NICAM was only 32 ksps, so 15kHz is about the absolute upper limit
It uses a 14 bit 10+4 structure, so in any data block you only get 10 bits of resolution. This is marginal for low level detail in a frequency band far from a strong signal which is at a frequency where the ear is insensitive

We always called it 13 bit . Doubtless you are correct . When learning about it there was no internet and the library didn't really have much on it . Hi Fi News was good as it got , they didn't go into working detail . One must remember computer speak is common now , not so then . We had no point of reference . I seem to remember the BBC saying that they were very surprised Philips never contacted them about digital . The BBC tests if I understand correctly were done using expert listeners . All of this data would have been shared with Philips if they had asked . Doubtless the man-hours devoted to it were considerable . I have to say Nicam is so good as to make me doubt I can hear it in use most of the time if not using a larger than life volume . When one considers it has 15 kHz on a good day . Then a Brick-wall filter to get rid of the 19 kHz pilot tone . Next the mind boggling circuits if 1972 , it is the miracle CD never was . The magic of the BBC research was to know what compromised could be used and ones that couldn't . Pumping effect was deemed to be OK as the volume needed to hear it would be excessive . Also most systems were well into noise by then . I would guess the BBC had 20 dB between digital effects and the noise of the best put together program material . I wonder if the BBC knew of noise dither ?I bet they did ?

I guess I never realized the move to 14 bit was when the Near Instantaneous label was first used . In principle I feel it was the same system albeit better .

The BBC PCM / NICAM Story
 
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The BBC used to transmit FM around the country as a digital signal and analogued it at the transmitter. The digital signal was a companded 14bit 15kHz.

This when we listened to FM sounded good (sometimes very good). We generally did not know that we were listening to a 14bit digital signal. We were after all listening to the BBC's FM radio.

Very much later Nicam (for television sound) was brought in.

I suspect they adopted the same companded 14bit simply because it already existed and it was already accepted as providing a very good quality when the BBC did it right.

The difference between FM radio and Nicam is that the analoguing of the digital signal is done at the transmitter for FM and we have it done inside our (build down to a price) compromised TV dacs.
 
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