Quote:
Originally Posted by Currawong /img/forum/go_quote.gif
If you are unfamiliar with high-end gear, how can you make the first statement?
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I am not unfamiliar with high end gear. I am just unfamiliar with Tandberg preamps, and the B22 amp.
I have listened to high end gear several times : Electrocompaniet, Etalon, Air Tight, Accuphase amps, Forsell, Roksan drives, Counterpoint, Audio Note DACs...
I also experimented with a lot of tweaks : DIY cables of all kind (including power cables)... no more than 10 years ago, I used to play CDs in a drive that I had taken away from its case, and installed on a 40 kg piece of granit, itself isolated from its concrete stands.
I used to clearly hear differences between all that. But the first thing that bothered me was that high end gear did not sound better than low end one. Often worse, to my ears, and that my perception was usually the opposite of what was commonly accepted : I prefered optical Toslink fiber to coaxial, I prefered the internal DAC of my DAT deck over an external one...
Then I began to notice changes completely unrelated to the system. One day the sound was marvellous, the next day awful. This phenomenon is experienced by most audiophiles. The culrpit is often said to be the mains quality. However, sometimes I had the occasion to compare the sound of my system to the one of my father, 1 km away in the same town. I found one day where my system sounded much better than his, and another day where it was the opposite. I didn't think that the mains quality could vary that much across a short distance in the same town. On top of that, the quality variations from one day to the next were bigger than all the cumulated improvements that I had done on my system.
I also had the occasion to realize that some of these differences were psychological. Sometimes the sound of my neighbour small boombox seemed to play at very different paces. Not different speed, because I would have immediately noticed the timbre modification, just a different psychological feeling of tempo.
I also realized one day that the color that I had mentally attributed to the sound of some albums, dark, light, grey, colorful, according to the mood of the music, was actually exactly the color of the sleeve.
I first thought the sleeve artist were right on the spot, because they always use the graphic mood that goes with the music of the band. But the accuracy of the matching was too good to be honest. I realized then that I had never attributed any color to the music that I only had on cassette tapes copied from vinyl ! I understood that I had unconciously put the color of the sleeve to the sound, while I thought not having done so.
Then, with Internet, I began to perform ABX tests, in order to test mp3 quality. I quickly applied this method to anything I could : recordings of the input of my amplifier vs the output, of the same record played in the analog input, and through the ADC/DAC of my DAT...
The result was clear : I knew what differences there were between all these signals. The fact that it was not there on the recordings that I was ABXing in the computer could not be explained by poor performances. Differences had just vanished both from the recording and from the original gear at the same time.
Listening more carefully, I could also rule out the possibility that the gear did loose its difference over time (bad day for it, not hot for a long time enough, too well burned-in etc), because I was not able anymore to match the memory I had of the sonic characteristics with the actual sound.
I knew the original sound of A and the original sound of B. But listening to A, B, or X,
I could not tell at all if they sounded like the old sound of A, the old sound of B, or somewhere in between.
The difference that I had in mind was clear as night and day. Muddy sound vs sharp sound. But frustratingly, I was unable to tell, listening to the sound if it was muddy or if it was sharp.
It was the same sound as ever. Very familiar, the sound of my old stereo system. But it was like if the part of my brain that was able to process "muddiness" had eventually stopped functionning. Instead, the sound was neutral.
And this was not the first time. I could remember these moments when I used to demonstrate the superiority of a tweak, like the addition of an external DAC to a CD Player, to someone who was not into hifi at all, with the puzzled face on him, who seemed to think "poor guy, completely nuts", while the tweak willingly stopped improving the sound (I could not hear the difference either), just at this moment, just to make a fool of me.
All these moments suddenly took a completely different meaning in my mind, as I was experiencing them at will under the ABX protocol.
I even caught a sonic difference during its very disappearance from my brain. It was the difference between a 24 bits / 96 kHz recording of an LP, vs a 44.1 kHz 16 bits one.
The two short wav files were completely different. The ABX would be a piece of cake.
As soon as I hit X for the first time, it was like another part of my brain fell off ! The difference vanished immediately from X, from A, from B, from the original wav of A played outside the ABX software and from the other original
wave file.
The worse is that all these samples sounded exactly like before to my ears. That's what I refer to with a "part of my brain". It is not at all like if there was listening fatigue, too short samples, or too fast repetition. In this case, I would have clearly heard that the rich details and beautiful timbre of the 96 kHz 24 bits recording had gone away, that I could not hear them anymore. But this was not the case. They were still there. On both recordings. Not especially more on one or the other. I just had not paid enough attention to their exact location. I was discovering that, changing my way of listening, I could hear all these qualities on the 44.1 kHz 16 bits files, but also all the defects on the 96 kHz 24 bits files. It was just a matter of attention.
It took quite some time until I got used to appreciate all the qualities and problems of a given system, without unconciously filtering out the ones that didn't seem to fit with my preconception. Some times, I was still mistaken with strong feelings about sound quality, that were just not there.
But one day, I found that one of these difference (between recordings of a vinyl made with two different stylii) was coming back again and again.
ABX : no difference.
Regular listening, the difference comes back.
ABX : no difference.
Regular listening, the difference comes back.
Imaginary difference do not use to come back like this. So I analyzed more carefully the sample, and finally found the obvious. There was actually some crackling on the left channel. And then I could ABX them at last.
Sorry for the off topic
Quote:
Originally Posted by haloxt /img/forum/go_quote.gif
Everyone to date has failed abx tests between an mp3 player vs. a supposedly hi-end system.
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Gbo and I ABXed a discman against a CD player :
homecinema-fr.com • Voir le sujet - Tentative de mise en évidence de difference entre DVD et DAC
Gbo found that the discman was not playing at the same speed.
I didn't hear that, I heard the distorsion introduced by the compression algorithm of the anti-shock buffer.
Quote:
Originally Posted by haloxt /img/forum/go_quote.gif
I can't hear a difference between $500 headphones and apple ibuds.
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I can, and according to
the measurments of headphone.com, they are way bigger that
the audible threshold.
Quote:
Originally Posted by haloxt /img/forum/go_quote.gif
No difference between 192kb mp3 and cd-quality.
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I can ABX some hard-to-encode samples at 320 kbps with the last version of the Lame encoder, and no internal clipping :
homecinema-fr.com • Voir le sujet - ABX de matériels bas de gamme. Mais pas seulement .)
Quote:
Originally Posted by Berlioz /img/forum/go_quote.gif
"Keep in mind that an external DAC will only decrease sound quality, in the unlikely possibility that it changes anything at all."
Can anyone back that up? I've never heard that before, but I'm curious how that would be so. Could anyone explain it to me? Thank you.
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Quote:
Originally Posted by AtomikPi /img/forum/go_quote.gif
I think that's false. While it may be that an external DAC is no better than internal, there may be slight benefits due to a decent DAC chip, lack of interference because it's a separate enclosure, etc. For example, feeding a cheap mp3 player's out to your amp is probably not a great idea, similarly feeding the out of your laptop or motherboard or maybe even cheap soundcard would probably not be ideal, but even a cheap DAC is probably going to sound as good as a pricey one.
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That's right. Motherboard integrated chips often have a lot of background noise, and are unable to playback properly the udial test sample, because of aliasing.
But soundcards like the Audigy have good signal-to-noise ratio. Sometimes even better than CD players !
I was referring to non-oversampling DACs, that are not uncommon in the high end.
The effect of not oversampling introduces distorsion (treble roll-off), and this is audible in ABX :
homecinema-fr.com • Voir le sujet - FAQ sur le suréchantillonnage
Jazz also says here that a treble roll-off is visible on every Wadia CD Player :
http://www.head-fi.org/forums/f133/i...ml#post5501442
Depending on its amplitude, it might be audible, while on good computer soundcards (is the Audigy in the "good" category, I'm not sure), there is no such roll-off.
And in blind tests, treble roll-off is audible, while the claimed transient improvement is not.
Also, the only successful ABX of
Matrix-hifi between DACs was the Sony Discman against the Audio Note DAC 3, and all the listeners agreed that the discman sounded better !
This is consistent with the fact that the Audio Note uses valves, that introduce distorsion. And the same discman could not be differenciated from other high end solid state DACs.
There are many examples of very high end gear, in DACs and amplifiers, that are so badly designed that they introduce a lot of distorsion, sometimes audible, while it is seldom the case with low end gear.
Douglas Self found some examples in amplifiers :
Douglas Self Site
Recently, in a french magazine, a tube amp was reviewed. One of the most expensive in the world (somewhere between 100,000 and 300,000 euros). The measured THD was 10 % !!
Quote:
Originally Posted by Oedipus Rex /img/forum/go_quote.gif
First of all, my Shanling cd-player has a nice option of enabling and disabling upsampling on the fly,
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There is a difference between oversampling (if your DAC doesn't, you get rolled-off treble), and resampling (a cheap tweak to mix different sounds inside a soundcard). Upsampling is yet another thing. It's reasampling from 44.1 kHz to 96 or 192 kHz.
The process is lossy and should only decrease quality, though it is unlikely to be audible (unless it is badly done)... unless the DAC is badly made too, and performs well only at 96 or 192 kHz.
Quote:
Originally Posted by Oedipus Rex /img/forum/go_quote.gif
When you say that "Headphone outputs of external power amplifiers for speakers may not be as good as a soundcard output." what exactly do you mean? Could the amp somehow disturb the signal?
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Not the amp, but the attenuation circuitry that feeds the jack output from the seaker output.
With Nitri, a french forumer, we measured the effect on the frequency response, and could ABX the difference successfully between a Marantz integrated amplifier, and a dedicated headphone amplifier on an AKG K-400.
I recorded samples taken from the headphone output while the cans were working and disturbing the attenuation circuitry. You can listen to them here, at the bottom of the first post :
http://www.head-fi.org/forums/f133/h...ne-abx-429619/