I will. You guys are putting together sims with made up data, aren't you reversing the process? You measure something repeatably and try to make a model to fit the data. Folks who read my first article will clearly see that I made this observation and at the time simply said "I don't know". Also please observe the PS cap data is almost perfect i.e. there is no DA network (relative to mica at least).
It's known as the real part of the capacitors impedance vs. frequency (you don't have a Russian cousin named Sergi by any chance). A joke Thorsten, I cretainly respect your work. Bridges are made to work at MHz and are looking for losses in RF circuits. I have not seen a market for 5G Ohm audio frequency impedance bridges. The real part of the impedance always has, in the limit, Johnson noise.
My amplifier will remain undisclosed for now because it is part of part II of my article, but it suffices to say it is capable of being used as an input to this bridge.
I just had an idea, when I get back on Wednesday I will try 50pf of PC board matierial known to have horrible DA.
Thanks, I have free access when I get back. PM noise makes sense as now it hurts in RF circuits. If you extend the plots to the right to a virtual meeting point it will be at a frequency over which the noise per se can not be a problem. This looks to be less than 100kHz. But at RF there is mixing up.
EDIT - Got it over VPN, seems same issue though they use their own slightly esoteric way of describing the problem. I guess I was unlucky it looks like almost anything is better than SM.
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I am interested in those experiments. Can you provide more details on what they are ?
did you miss the point that mastering can be, has been found to be different between the layers on Hybrid SACD
how did you determine if they even had the same average level on playback
the cynical would say Sony has an interest in SACD layer sounding different than the CD layer – especially on Hybrid Discs where the consumer can easily compare – of course incompetence is always the preferred explanation ahead of conspiracy
if you want to compare formats you need to start with the high res source yourself - and competently use best practice in the processing to CD resolution
I am not dogmatic on the transparency of CD Audio - but so far the evidence seems fairly strong that any deficiency is not readily heard with Music, at ordinary listening levels
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As long as people have the opinion that CD is 'good enough' and tend to rationalize the reasons other people do not find it so, we are at an impasse.
I have fought this difference between peoples points of view for more than 40 years, in analog tape recorder design, phono reproduce design, magnetic recording in the film industry, loudspeaker design, etc, etc.
For example, what is cited here as analog tape recorder limits, did in fact exist, with MIDFI production and compromises, typical of many commercial studios. Why should they use high speed, the best tape, wide tape tracks? It costs money to do this, think of the BOTTOM LINE! The studios do, for sure. Yet, that does not exploit the POTENTIAL of analog magnetic recording, yet it is reflected by recordings from Keith Johnson or Wilson Audio. If you are to have HI END audio reproduction, you have to have examples of audio software that are pristine, and not compromises due to cost cutting in the marketplace.
For example, the Wilson Audio 'Ultramaster' can reproduce 10KHz square waves with a 10uS rise-time, has an 80 dB dynamic range, and its master tapes will probably last for many decades. This is so, because it operates at 30ips, with full track, 2 channel, 1/2 inch tape. Expensive, yes, but what is cost, if you get highest quality?
Even better is 'direct disc' recording, eliminating the tape recorder from the loop. This really is better, at least compared to an analog recording transferred to a vinyl record.
Too bad they don't make them anymore to any extent. A digital copy from either a direct disc recording or an Ultramaster analog recording is ALWAYS INFERIOR. Dave Wilson made an A-B test to prove this, decades ago.
I can't argue with some professional's opinion, where they are happy with CD, etc. It is just that comparisons of two mediums should be fair and balanced. After all, my associates and I had to fight the industry to make better recordings, even though our efforts were ignored by the majority of the commercial audio industry, my critics saying to me, at the time, it's too expensive, and who needs a better S/N, anyway? Now, the compromises that I fought against for decades, are thrown up here as the limits of analog recording, but they are not. Let's keep this in mind.
I have fought this difference between peoples points of view for more than 40 years, in analog tape recorder design, phono reproduce design, magnetic recording in the film industry, loudspeaker design, etc, etc.
For example, what is cited here as analog tape recorder limits, did in fact exist, with MIDFI production and compromises, typical of many commercial studios. Why should they use high speed, the best tape, wide tape tracks? It costs money to do this, think of the BOTTOM LINE! The studios do, for sure. Yet, that does not exploit the POTENTIAL of analog magnetic recording, yet it is reflected by recordings from Keith Johnson or Wilson Audio. If you are to have HI END audio reproduction, you have to have examples of audio software that are pristine, and not compromises due to cost cutting in the marketplace.
For example, the Wilson Audio 'Ultramaster' can reproduce 10KHz square waves with a 10uS rise-time, has an 80 dB dynamic range, and its master tapes will probably last for many decades. This is so, because it operates at 30ips, with full track, 2 channel, 1/2 inch tape. Expensive, yes, but what is cost, if you get highest quality?
Even better is 'direct disc' recording, eliminating the tape recorder from the loop. This really is better, at least compared to an analog recording transferred to a vinyl record.
Too bad they don't make them anymore to any extent. A digital copy from either a direct disc recording or an Ultramaster analog recording is ALWAYS INFERIOR. Dave Wilson made an A-B test to prove this, decades ago.
I can't argue with some professional's opinion, where they are happy with CD, etc. It is just that comparisons of two mediums should be fair and balanced. After all, my associates and I had to fight the industry to make better recordings, even though our efforts were ignored by the majority of the commercial audio industry, my critics saying to me, at the time, it's too expensive, and who needs a better S/N, anyway? Now, the compromises that I fought against for decades, are thrown up here as the limits of analog recording, but they are not. Let's keep this in mind.
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kinda oxymoronic there John - Digital Audio has really advanced in 20+ yrs
have you heard this tried with this century's best hi res ADC's - maybe Plangent Processes tech for reducing the mechanical tape stick/slip FM modulation?
there really are 120 dB SFDR monolithic ADC now, and pro studio ADC promising even better - I would recommend higher than CD sample rates on simple engineering conservatism principles - which is Studio practice - as the kids say - Duh!
as I said I think being agnostic on CD transparency is still warranted with only 2 much smaller studies appearing since Meyer, Moran casting doubt
the only argument for CD today is as a "good enough" consumer distribution format
What you allude to was very true with 16-bit digital. But those days are over now that we have 24-bit systems. I record at -18 dB and never have to worry about clipping, no matter how excited the musicians get (they always play louder during the show compared to sound check, no matter how much you plead with them to give you a 'real' level). Considering the discussions here about the so-called headroom in tape, you can have the same headroom in digital but without the level-dependent distortion of tape.
Also, compare live digital mixing consoles. They are designed to run well below 0 dBFS from input to output, and the meters are marked to keep the operators away from digital clipping. If only we could convince record labels to release 24-bit recordings with this much headroom - and therefore no dynamic level compression - then digital could sound like a live concert.
well there is dither...
but how many ways do I have to say I don't "know" that Audio CD performance limits are "transparent" for all music, all listeners - as a negative result (no one can hear the difference) its not something than can be proved
the current generation of audio mastering/mixing pros overwhelmingly use hi res digital, consider bouncing to analog tape, using tube preamps as just adding sound effects
if you really want to disprove the transparency of the CD standard compared to hi res formats I suggest Suzuki method trained prepubescent girls as subjects - not exactly the Stereophile magazine demographic that drives high end audio sales: 98+% male, median age 41
Who Are You? | Stereophile.com
face it John your customers we hear so much about, their discerning tastes "proving" your designs - they're half deaf already
but how many ways do I have to say I don't "know" that Audio CD performance limits are "transparent" for all music, all listeners - as a negative result (no one can hear the difference) its not something than can be proved
the current generation of audio mastering/mixing pros overwhelmingly use hi res digital, consider bouncing to analog tape, using tube preamps as just adding sound effects
if you really want to disprove the transparency of the CD standard compared to hi res formats I suggest Suzuki method trained prepubescent girls as subjects - not exactly the Stereophile magazine demographic that drives high end audio sales: 98+% male, median age 41
Who Are You? | Stereophile.com
face it John your customers we hear so much about, their discerning tastes "proving" your designs - they're half deaf already
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Decades ago, A/D converters were very primitive compared to today. Has anyone repeated Dave Wilson's proof with modern digital equipment? I can't even listen to digital music made before 96 kHz became available, and even today the 192 kHz converters sound better even if they're just running at 48 kHz.
Your comparison is unfair. It's like picking a tape versus vinyl (or pick your competition) test done before the Ultramaster was invented, and then dismissing all tape including Ultramaster because the results were poor at one time.
For the record, I am not happy with CD. 18- to 19-bit would be a minimum, and 24-bit is the only standard we have. CD is convenient, and it's better than MP3, but I mostly put my money into 24-bit recordings (although they vary in quality so much that it's a nightmare to witness).
I suggest you try several samples. One baseline. one baked and one that has had an AC signal of a volt or so applied for a few days. I suspect that there will be differences!
There are some interesting issues with how we hear involved. If you live in a city, the outside noise may be 50 dba. Even a simple wall will drop that by 20 db. Windows much less and are the major leakage.
But if your background noise level is 35 dba and you play your music at 75 dba average then the peak levels can be reasonably expected to hit 95. As the noise measurement is the total weighted noise over the "Audio" bandwidth it is much lower in the critical bandwidths that you can discern.
There is one fellow who claims that the reason why 1/3 octave equalizers work so well (!) is that they match critical bands (!??!). So even using only 30 critical bands as a criteria that would allow 20 x log(30) additional range. That would give you 15 bits of range.
Of course the recording may have a bit of headroom, your hearing might just be a bit better (or even normal!), the noise level lower, you might play louder, or even listen up close to the loudspeakers. Headphones of course would require far more bits.
We are all Martians, here. John, with his 40 units of plain aluminum, " 1 power supply by stage's preamp"; ultra secret and more expensive than a car, me, with my 10Mhz/1500v/µs 140w power amp, you, folk with your...All Martians looking for some intergalactic Graal..
Dead crazy.
Vinyl does not exist any more, even CD is dead, young people does not buy his "music ?" on a solid support any more. Analog recording ? What is that ?
LP s ? Most of my visitors at home looks to my vinyl collection, amused, near intrigued, as i was with the 78rpms of my grand-mother, looking at his phono and his so beautiful articulated coper horn, when i was young. They examine the same way my radial arm turntable.
Even me, recently retired dinosaur, all my music is on my hard disk, now, and very rare are the moments i put an old vinyl on the turntable or a cd in the machine.
Better not to fight between us, about our different approaches of a strange passion that nobody around us (out of our professional audio environment) even understand.
Time to share as much as possible all what we have experienced or discovered, to help young people to reinvent a new music dead in the 80th.
Studios are dead, one after the others. Young musicians record in their home with their computers. Did they care about bits or sampling frequencies ? Record companies do not sell the cheap expensive records they had produced in the last available big studio and don't even understand why. As said Little Feat, we are very near "The Last record album", many years ago.
And it is not a pity, technology had made impressive improvements during the last 80 years in audio/video and will continue that way, i suppose. In white rooms of laboratories.
People like John are listening to components sounds, like a cook taste and imagine the products of his future recipe, big companies don't even know what is in their VLSIs. (they assemble programs)
On my side, i'm pretty proud to have been a part of this adventure, at my little level, and to have lived so many fantastic moments during the 70th with all those incredible long haired musicians. Both with my mikes and soldering iron.
I will live this forum, will publish on my web site instead, but i wanted to kiss you good bye. You all are very interesting and nice people. Thanks for all.
Dead crazy.
Vinyl does not exist any more, even CD is dead, young people does not buy his "music ?" on a solid support any more. Analog recording ? What is that ?
LP s ? Most of my visitors at home looks to my vinyl collection, amused, near intrigued, as i was with the 78rpms of my grand-mother, looking at his phono and his so beautiful articulated coper horn, when i was young. They examine the same way my radial arm turntable.
Even me, recently retired dinosaur, all my music is on my hard disk, now, and very rare are the moments i put an old vinyl on the turntable or a cd in the machine.
Better not to fight between us, about our different approaches of a strange passion that nobody around us (out of our professional audio environment) even understand.
Time to share as much as possible all what we have experienced or discovered, to help young people to reinvent a new music dead in the 80th.
Studios are dead, one after the others. Young musicians record in their home with their computers. Did they care about bits or sampling frequencies ? Record companies do not sell the cheap expensive records they had produced in the last available big studio and don't even understand why. As said Little Feat, we are very near "The Last record album", many years ago.
And it is not a pity, technology had made impressive improvements during the last 80 years in audio/video and will continue that way, i suppose. In white rooms of laboratories.
People like John are listening to components sounds, like a cook taste and imagine the products of his future recipe, big companies don't even know what is in their VLSIs. (they assemble programs)
On my side, i'm pretty proud to have been a part of this adventure, at my little level, and to have lived so many fantastic moments during the 70th with all those incredible long haired musicians. Both with my mikes and soldering iron.
I will live this forum, will publish on my web site instead, but i wanted to kiss you good bye. You all are very interesting and nice people. Thanks for all.
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jcx said:
That's really grasping at straws. No, I've had no complaints with the CD layer of SACD in comparison other CDs. They often sound very good. Just not as good as SACD in the comparisons I've made. They often sound closer in quality than the separate releases of the same music.
Sony's interest in SACD? Well, that's a real hoot. They long ago quit releasing SACD recordings. Yep, they get some royalties from the classical releases that are still coming out on SACD - not even a blip on the radar as far their bottom line is concerned, I'm sure.
If engineers aren't capable of putting out quality CDs equal to SACD, then who needs the CD? No, I'm ready for a high resolution format, not that the industry cares.
The Sony PCM F1 was barely 16 bit, had a really noxious analog low pass filter on the input and a single converter for both channels. The Nakamichi version was slightly better. The output is really unusable by today's standards. Reference Recordings has a number of masters from that era made with those machines that have been abandoned. They have been re-transferring the analog masters from the KOJ three track for the high resolution re-releases. The new transfers are all done with Pacific Microsonics model 2's, which represent about as good as a digital capture system can be today.
The performance of current 24 bit converters either way, is much better in every aspect than anything from the dawn of digital audio, unless you are enamored of artifacts and colorations.
De-emphasis was so badly misused and implemented that it has been pretty much abandoned and some new systems can't implement it lacking a way to do it.
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