The biggest shortcoming of SACD is that most of its proponents are... - 9fold 04:40:32 01/31/03 (3)
 Psst, 9fold...., - Rod M 15:37:32 01/31/03 (2)
 Re: Psst, 9fold...., - 9fold 04:47:17 02/01/03 (1)

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 The biggest shortcoming of SACD is that most of its proponents are... - 9fold 04:40:32 01/31/03 (3)
 Psst, 9fold...., - Rod M 15:37:32 01/31/03 (2)
 Re: Psst, 9fold...., - 9fold 04:47:17 02/01/03 (1)
 Re: Psst, 9fold...., - Rod M 08:20:58 02/01/03 (0)
 keep grasping for straws - rafaello 14:30:48 01/30/03 (0)
 Of course it does... isn't it the reason why all of you are here?!! (nt) - Eric LeRouge 14:21:53 01/30/03 (0)
 Re: Have you noticed.....(wild conjectures wanted) - Tom Doherty 12:01:02 01/30/03 (0)
 i haven't heard any shortcomings in either format ... - Christine Tham 11:47:39 01/30/03 (0)
 Only a troll keeps.... - Frank 10:47:24 01/30/03 (46)
 Watch it, pal ;-) - El Trollo Loco 01:24:14 01/31/03 (0)
 Frank, is that why the S/N ratio is affected well below 10 kHz? - Jim Pearce 11:01:39 01/30/03 (11)
 if the S/N ratio reduces from 130dB to 120dB (for example) ... - Christine Tham 11:51:24 01/30/03 (9)
 How about well below 90 dB, Christine? - Jim Pearce 12:03:50 01/30/03 (8)
 oh, by the way, even 90dB is actually a very *good* S/N ratio - Christine Tham 14:09:12 01/30/03 (5)
 Re: oh, by the way, even 90dB is actually a very *good* S/N ratio - Jim Pearce 14:22:36 01/30/03 (4)
 again, that is all as per spec and intentional ... - Christine Tham 14:33:51 01/30/03 (3)
 On the contrary, the Stereophile tests show that... - Jim Pearce 07:18:11 01/31/03 (2)
 no misunderstanding at all - Christine Tham 14:07:57 01/31/03 (0)
 Not exactly... - Frank 07:32:40 01/31/03 (0)
 i don't normally read stereophile, but ... - Christine Tham 13:52:03 01/30/03 (0)
 See my post below - Frank 12:10:33 01/30/03 (0)
 Exactly. - Frank 11:07:31 01/30/03 (0)
 utter nonsense - tunenut 11:01:05 01/30/03 (32)
 Evidence... - Frank 11:52:10 01/30/03 (1)
 And - Frank 11:54:53 01/30/03 (0)
 Reduced S/N ratio? - Jim Pearce 11:24:36 01/30/03 (29)
 can you give me a link to these charts? - tunenut 11:32:37 01/30/03 (28)
 Stereophile.com - Jim Pearce 11:48:08 01/30/03 (27)
 I looked at the 777 review... - tunenut 12:58:58 01/30/03 (26)
 It is the noise level that I'm looking at. - Jim Pearce 14:25:21 01/30/03 (4)
 I will need to think about this... - tunenut 14:48:45 01/30/03 (0)
 Just compare the graph's - Frank 14:40:50 01/30/03 (2)
 Re: Just compare the graph's - Jim Pearce 08:08:54 01/31/03 (1)
 Re: Just compare the graph's - John Kotches 07:19:21 02/01/03 (0)
 Re: I looked at the 777 review... - Frank 13:16:17 01/30/03 (20)
 same thing is happening on the regular CD player... - tunenut 13:38:06 01/30/03 (19)
 No the signal is comming from a sacd disc and not... - Frank 13:50:32 01/30/03 (18)
 the Meridian 508.24 CD player shows the same thing... - tunenut 14:03:10 01/30/03 (17)
 They tell why on the same page - Frank 14:44:03 01/30/03 (16)
 here is the correct reason... - tunenut 16:57:14 01/30/03 (14)
 No, - Frank 03:01:56 01/31/03 (0)
 Yes and no. - Jim Pearce 20:31:48 01/30/03 (9)
 I am only talking about CD players now... - tunenut 21:05:54 01/30/03 (8)
 It makes no sense... - Frank 04:39:29 01/31/03 (1)
 Re: It makes no sense... - Jim Pearce 08:01:45 01/31/03 (0)
 Agreed. - Jim Pearce 21:15:17 01/30/03 (5)
 The DSD sample rate for the sacd implementation - Frank 03:13:04 01/31/03 (0)
 don't know - tunenut 21:22:35 01/30/03 (3)
 The obvious conclusions are.. - Jim Pearce 21:40:37 01/30/03 (2)
 here is the best I can do right now... - tunenut 21:54:11 01/30/03 (1)
 JA is going to write a series of articles on the tests. - Jim Pearce 22:19:10 01/30/03 (0)
 thank you - that makes sense - Christine Tham 18:21:26 01/30/03 (2)
 That's right Christine, they're just graphs of the.. - Jim Pearce 20:44:21 01/30/03 (1)
 can you please go easy on the sarcasm? - Christine Tham 21:39:58 01/30/03 (0)
 Re: They tell why on the same page - John Kotches 15:54:24 01/30/03 (0)

In the brittish Hifi Records Review magazine they did the experiment by overlaying a 24/96 recording with dsd noise. A difference between the original recording and the dumbed down dsd version was detectable.
A real dsd recording suffers more because noise shaping affects the sound through in band filtering. Noise is shifted up in the spectrum and some of the musical content is shifted in the process as well.

Frank

This simply does not happen. This is a product of your active imagination. No musical content gets shifted. Not even the slightest percentage. None.

Frank

no ultrasonic bat mating calls on SACD or anything at 10kHz or above either

even cds sound quite good under the right conditions

people who have a barrow to push usually find mud along the way

that argument is as spurious as the "PCM signature" argument against DVD-A

Noise output of the SCD 1 with a digital 'black' signal.

The same player's noise with a -50dB test signal.

Notice the rise of the noiselevel. Where does that energy come from?

Frank

Clear evidence that the noise gets modulated. And so will musical content in the upper frequency range.

Frank

Clear evidence that the noise is modulated by the signal.
The level of noise isn't really important.
What is important that the so called dsd noise is in fact distortion that doesn't belong in the signal.

Frank

• http://www.stereophile.com/showarchives.cgi?491:6

Maybe they put the signal generator too close to the player- who knows.

It's got nothing to do with DSD or the noise being modulated by the signal.

The rise for the cd signal is less severe than the sacd's modulation but it indicates 1 bit dac technology is used.

The signal modulates the noise there's no doubt about it.

Frank

yes - it rises sharply after that - to round -92dB at 20kHz in fig 4

which proves my point. these are all "within spec" as far as i am concerned, and at these levels the resolution capability of the dacs and analog circuitry are limiting factors.

what i do concur is that sony/philips marketing blurbs about frequency response to 50 kHz are clearly misleading - the signal is pretty junky above 20kHz. but that's fine, i'm not a bat.

• http://www.stereophile.com/showarchives.cgi?590:5

let's say you are listening to music at rock concert like levels of 110dB. you are getting an overall S/N ratio of effectively 60-70dB at best.

in a worst case scenario (air-con, projector turned on) the S/N ratio may well drop to 30-40dB

this is all old news to mixing engineers which is why you will seldom hear content mixed at below 30-40dB (an exception is pat metheny who says he deliberately introduces content at -40-50dB for headphone listeners)

the S/N ratio on my old amp was only around 80dB. yet i have never heard the noise floor on this amp, even when cranking the volume all the way to 11 :-) (of course, there is noise if my ears are right next to the speakers, but not at normal listening position.)

so i very much doubt (if the player is performing to "spec") that the high frequency noise in sacd is detectable. of course, this is not to say that the noise may not induce artefacts (amplifier circuits oscillating, speaker colouration, phase shifts, whatever) that are detectable. but these are all equipment limitations.

I call that modulation. Now it's only noise but what if a 10kHz signal is present next to the 1kHz tone?
It gets also modulated.

Frank

It's evidence of 1 bit dac technology and noise shaping

Frank

Regards,

Regards,
John Kotches

They say in the write-up that the noise floor in this graph is the same as the noise floor of the dither in the input signal.

That is your answer. This has nothing to do with noise shaping. They are inputting a signal with a rising noise floor, so that is what they are getting at their output.

This is why all the Stereophile graphs of this test output look pretty much the same.

Certainly, the noise shaper is not moving any signal energy. Nothing of the sort happens.

Well I looked at these output charts for about 5 different CD players. They had slightly different wiggles in slightly different places. But they were all basically the same shape. And then I read the text in the latest issue.

It is very obvious that the change in the noise floor between "digital black" and the dithered signal is primarily due to the noise floor in the input signal due to the dither. It has nothing to do with whether the DAC is single bit or not.

OK this applies to CD players. Now we all know that there is a noise floor that increases in SACD and it appears in the Stereophile graphs to increase rapidly above 8 kHz. This is part of the design.

It is still not the case that the noise shaping shapes the signal. Frank's logic, which was not true for CD, is no more true for SACD.

i wasn't even replying to your post

OK, why does the 777 graph not look like this? I would think it should. I would think that machine is operating out of spec and should be repaired. I don't think the noise is designed to be as high as that shown in the graph.

• http://www.stereophile.com/showarchives.cgi?180:14

With dsd and noiseshaping you see the rise in noise only above a certain frequency.

Frank

The rise in noisefloor is just showing that the noise shaper is becoming less effective beyond a certain frequency.

It also shows that distortion rises and that resolution is dropping.

Frank

I think the dither is applied to the 16bit pcm test signal.

And of course the noise is in the dsd signal. And my point is that the dsd noisefloor in that signal is modulated by the signal.
The digital black is just a dsd signal with a signal just high enough to keep the muting circuitry from activating. In effect this is the bottom noise floor of dsd (on that partical player).

The question is where the test signal is derived from. From a signalgenerator with noise in it's output or is it a math derived 'ideal' testsignal. In the latter case the noise level should be the same as the bottom noise curve.
If it's from a signal generator the rise in noise level should be the same on different machines asuming the same test disc is used.

Frank

Redbook players with 1 bit dac's and noise shaping show the same noisespectrum but with a rising curve in a higher frequency range.
That's because the 1 bit dac's usually oversample at 128 or 256 times.

Frank

the fact that many cd players exceed the design goal is due to techniques such as oversampling.

what i stated was that i believe sony/phillips designed dsd to be no worse than the cd spec (ie. 90dB) in the worst case.

in which case, any s/n ratio better than 90dB is "per spec" in my opinion.

i could of course be wrong and will be happy for someone to point this out. but until then, i am not concerned with the results in stereophile since i don't believe they subjectively impact the listening experience (as stereophile themselves point out).

While I'm here, I still don't like the idea of the hi-rez formats being split up. If it had been done at the beginning, it might have have been a good idea (it might not have as discussion of the two formats can be productive). My issue is that the split was done later on for the wrong reason. It was felt that separating folks was the best way to clean things up. That makes no sense. I will say, however, that things have not been as messy as perhaps many of us thought they would be since the split. I attribute that to many folks being challenged to behave. In any event, I still feel the split is wrong. What you, Chris, and any others involved should be striving for is one board for discussion of DVD-Audio and SACD (including universal players!) that is well monitored and that demands high level discussions. Sorry, but you guys took the easy way out by splitting the board.

As far as I am concerned, DVD-Audio is a high-resolution format, so discussions on DVD-Audio most certainly belong on the Hi-Rez Highway. The name "Hi-Rez Highway" in no way conveys a limit of discussion to SACD.

Finally, I will ask that many others have asked. Where should I post questions about universal players? Should I post them in both places? What a pain in the ass! If I post my questions on just one board, I might not get a full analysis of the player, as the DVD-Audio board will likely favor discussion of DVD-Audio playback capability. The same is likely for the Hi-Rez Highway with SACD.

If you look at the hi-rez marketplace, a growing number universal players are being released. For some companies, a universal player is their only foray into the world of hi-rez audio, and rightfully so. How ironic that at a time when universal players are beginning to occupy a significant plot on the hi-rez audio landscape that this site splits discussion of the two formats. Of course, as I said, this split had nothing to do with audio. There is a reason this site is called the Asylum.

:o(

I can't prove this, but I believe that the degree of noise modulation will increase as a function of frequency.....

I might not be expressing this well, so this is a 2nd explanation.

I suspect that the higher the frequency tested, the worse the noise modulation gets above the tested frequency.

Regards,

Regards,
John Kotches

Now, why did we decide to split the boards? Sure, the moderation issues were a factor, but not an overwhelming one. We do try to take a hands off approach as much as possible, so just cracking down is not an option that we like. However, those issues were only a part of the story. In the past, we've split off many, many forums. We do that because of three reasons: 1) The board grows too fast and is too active, 2) A large number of posts center on a specific sub-topic and 3) Specialty groups and less activity promote a better sense of community. I believe that we can agree that Hi-Rez was so active that topics simply disappeared to quickly to allow for thoughtful and lengthy discussions. That high level of activity was also affecting the sense of community.

As to where to talk about Universal players, take your pick. While that creates a small dilema, it's not uncommon. We have 3 tube boards, Tubes, SET and Tube DIY. The problem is the same and it hasn't been a problem. People pick the board where they feel most comfortable, know the inmates the best and feel is most appropiate for their purpose. If your primary concern is DVD-A performance, post about Universal players on DVD. If not, post on Hi-Rez or even Digital if redbook is a driving concern. I think we can all deal with a certain amount of crossover. However, from what I see, much of the discussion lies in the area of new releases and from that perspective, the split around technology seems to be working quite well.