JPN SHM-CD Blue-Spec

I could never hear any difference between any cdr's and god knows i tried enough.

The cd lathe thing stands out as working very well on some discs and not at all on others, i think it's down to the edge of the disc in some cases being quite ragged and out of concentricity with the centre so it causes procession which means the heads have to work harder to track and I believe the power supply effect of this feedsback into the audio circuits. I don't see the edge of my Police cd being any better than a standard cd, it's not lathed quality for sure.

I'm not aware on any cd player where accessing error correction is a considerable draw on the power supply, unlike laser tracking which can be significant. There's no reason why they would read any better than a standard cd, the headroom in the spec for optical transparency in Red book cd is huge, so improved transparency through better acrylic means bupkiss.

Laser optics have exactly diddly squat to do with jitter, jitter is everything to do with the data being interleaved with a time signal provided by a clock and then converted to audio by DACs which also require/provide a clock. All data read off a cd hits a FIFO buffer before being clock-synced and sent for conversion, errors in the read are corrected by CIRC before they hit the buffer, if they weren't you'd hear nothing, if the default no data state was 'mute, or random electronic chirping otherwise. ( interestingly my CA840 chirps and whistles when used with an Airport Express, so that's my default state, i never hear this from cd...)

Honestly I can measure no reason, nor propose a reason why a 'blu' cd should sound different from an identically mastered Redbook cd. If the edges are typically 'lathed' quality then maybe the 'balance' of the spinning disc requires less interaction from optical servos to track the disc as it spins, but even that has jack shit to do with the 'blu' format, just tighter physical tolerances in manufacture.

I remain thoroughly unconvinced.
 
Just scanned the web in regards Blue-spec and got this off www.cdjapan.jp, reading between all the sales mush,the claim is the improvement on the way the disc's are made read on....
Blu-spec CD format boasts a new approach to the faithful reproduction of music by utilizing the leading edge blue laser diode technologies optimized for the manufacturing of Blu-ray. During the manufacturing of CD, laser beam is pinpointed to encode data on the microscopic tracks molded on the polycarbonate plastic constituting the surface of the disc.

"Compared to the conventional laser beam used for the manufacturing of standard CD, the blue laser beam used for the manufacturing of Blu-spec CD has a shorter wavelength, allowing more accurate encoding of the data. The use of the laser also eliminates the need to use cooling fans that cause vibrations. Furthermore, polycarbonate plastic optimized for Blu-ray is used to ensure accurate reading of the data. Amazingly and importantly, Blu-spec CD format is fully compatible with standard CD players".

SHM-CD is claim the "Disc's are more reflective",I noticed that you said you have The Police Ghost in the machine" on SHM-CD,as well as a standard CD? If you compare both of the data playing sides,you should notice that the SHM-CD takes up more space on disc. Although,they don't make any sales patter about this, I can see the same on all the SHM-CD that I own.
I guess this is the bit I'm trying to point out,by making the pit's wider/longer,the disc then becomes easier to read, just like the effect of when playing a Lathed CD.

Anyway it's all interesting stuff,and great for myself to have a chat about slightly new formats.
 
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Ahh yes ....ebay prices.I'm lucky enough to have a copy of that disc on SHM-CD. Good news,as it having another pressing run in japan,and at the moment it's $19.29c. Ebay sellers are really taking the P**s at the moment on the price of some of these disc's. Anyway if you feel like a punt "you could always sell it on the ebay if you didn't like it,Ha Ha !" here is a link

http://www.cdjapan.co.jp/detailview.html?KEY=UICY-91415
 
bollocks.
CDs are stamped from a master just like records are, not burnt.

There is no benefit to more accurate pit edges it is not the edge of the pit that defines the data but the gaps inbetween them. The gaps are hundreds of times larger than the pit transitions.

If you better understood how CDs were made you would realize what bollocks they are trying to sell you.

The data takes up an identical space on the discs. Because it is the same data written with identical pits. They might well put deadspace between the tracks to dupe idiots but they can do nothing to change the data.

The rednook standard specifies pit size exactly, you can't just. Change them. The disc would not read.
 
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Ok it has been annoying me so much that companies try to spread disinformation like this that i've gone to the bother of drawing it all out.

Please bear in mind that i lived with a Philips optical engineer for 3 years as a post grad and that his PHD was in Blue laser optical data storage, we used to while away the hours....

anyway here's why they are selling you bullshit...

blu-cd-bollocks.jpg


Please bear in mind that a couple of companies make blu-spec claims but so far only jvc have shown that they actually do anything other than share a dvd pressing machine.
 
sq225917 said:
The rednook standard specifies pit size exactly, you can't just. Change them. The disc would not read.
Click to expand...

Sorry,your wrong on this one, Red Book Spec also allows for different speed tolerances on replay,and longer pit lengths,it had to,as you wouldn't be able CD play in such a wide range of CD players.
This is how Yamaha Patiented The Audio Master Setting on CD-R Writers, rather than me try to explain have a read of this link,anyway by increasing the pit lengths,a 80 Min CD-R is reduced to 68 Minutes. I've been using the Audio Master for years,and all my disc's play in new and Old CD-Players!

http://www.yamahamultimedia.com/yec/tech/am_01.asp

I can't coment on Blu-spec,and I can't even see where the data ends on Blu-spec,as it's not visable to my eyes.but I'm pretty sure SHM-CD is using the same approach,in regards to pit length, have you compared those "Ghost In the Machine" CDs yet?,as you haven't commented on it yet.
 
So what part of 'specifies pit size exactly' precludes that being within a range of values..? I'm aware of the % rotational veolcity deviation allowed under the spec, and also the variation allowed for in track pitch. Where do you think they managed to sneak 74 1/2 minutes from on a standard cd, it's the max allowable within the 'range' of the Redbook standard.

As i said having more accurate pit edges makes no difference to the overall data fidelity as the data is defined by the lengths of the pits and lands, not the transitions, which are many many times smaller. More accurate/smaller transitions do not improve playback.

Stretching the pit and land sizes out to the maximum allowed within the specified ranges of rotational velocity makes no difference, the larger pits allowed within the spec just have to pass the laser diode even faster than the the minimum spec size pits would. There is no gain here, unless you count loosing disc run time as being beneficial.

It doesn't matter how big you make them, within the spec range, you still have to read the equivalent to 44,100 samples worth of them per second. So the big ones go by faster making life harder for the laser optics.

The Yamaha stuff is bullshit marketing, just like the other stuff is, except they have a bullshit patent claim, untested so far to back it up. You don't have to prove your patent claims to get a patent, you just have to be first to make that claim, ask Tones he'll explain to you, there are thousands of bullshit patents granted each year that would never stand up to scrutiny. Mostly so people can sell you a bullshit product.

Even their light exposure test is bullshit, read it carefully, only their Audiomaster cd burner used their audiomaster cd-r, any change in errors after exposure to light could be solely down to the quality of the cdr themselves and have nothing to do with the actual way they were burned. They would need to have doubled up the test, using basic cd-r's in their burner to prove it wasn't solely down to the physical make up of their cd'rs vs cheaper substandard cd-r's selected for the rest of the test.

There's no science here just spin.

i know you want/need to believe in it because you have been duped into believing you hear a difference.

1. Audiomaster does not burn any less pit-jitter than any other cd burn, they all have to be within specification and every cd player makes perfect burns every time when burning computer data at 24x why should 1x be so hard?
3. Using the upper limit of allowed pit sizes within the red book spec requires faster rotational velocities because the data rate is fixed by the sampling rate of cd. No increase in accuracy can be gained from this, one cancels out the other.
3. Burning a cd stamper with a shorter wavelength laser only reduces the size of the pit transitions, the size of of these transitions is so much smaller than the size of the pits and lands themselves that it is mathematically inconsequential.

Obviously your belief is quite entrenched, but i'm happy to go through these items one by one with you if it means you'll end up seeing the light.


and yes, my GITM does appear to take up more space.
 
The audio master was an example,as you claimed that CD's wouldn't play in CD-Players if the pit size was different to quote

"The data takes up an identical space on the discs. Because it is the same data written with identical pits. They might well put deadspace between the tracks to dupe idiots but they can do nothing to change the data.

The rednook standard specifies pit size exactly, you can't just. Change them. The disc would not read"

It's simple really,the longer pits make it easier for the laser to read,and in theory you get more acurate date with less errors,similar to the lathed effect. I'm not claiming the data is difference. After all,some CD-P transports are better than others,are they not ? It's all IMO about making life easier for your CD-P laser to retreive the data as best as it can.

I guess will have to agree,to disagree on this one, but I have to say it's been great hearing a different point of view.Just how it should be,after seeing how direction on the "Frezzeing CD" post when it's a breath of fresh air.
 
Are you purposefully attempting to misinterpret what i write, or do i need to explain every tiny detail to you? If you don't understand the cd specification and how they actually work, that's fine, I'll assume you know nothing and explain accordingly, the fact that you misinterpret "exact speed" to be a single value rather than the obviously allowable range of speeds within the redbook spec kinda proves you don't understand it, or are trying to derail the discussion.

"cd's wont play in players if the pit size is increased" ( of course there's some small allowance for variability written within the spec, what idiot wouldn't accept that as a given, you aren't tripping me up here, i didn't think you knew so little about the spec that i had to explain every detail).

Your claim"Longer pits make it easier to read", the disc has to spin faster so that the same number of longer pits passes the read head each second. 44,1000 samples worth of data 'have' to be read every second, no ifs or buts about it. There is no potential for improvement with longer pits and lands, it is just a mechanism to account for the slight variations that exists in accuracy between motors that spin the cd's. The upper and lower limits of which are "defined exactly" by the redbook spec.

It is part of the Redbook spec, Yamaha didn't invent this, they just patented the claim that burning cd's at the upper limit of the pit and land length allowable within the redbook spec reduced jitter. it doesn't. Not only does it not improve jitter- because none can exist until after the data on the cd is converted to PCM data and synced with a clock stream, but it doesn't even improve the accuracy of reading data from the CD because the increase in "font size" (lets use an analogy) is offset directly by the fact your pages are running under your nose that little bit faster. If cd didn't have to read 44,100 samples worth of data per second, ie if you were just filling a buffer in less than realtime, then it might help improve the read accuracy. But Redbook is real-time.

I understand that the logic behind this might appear to be less attractive than grand marketing claims backed up by no less a thing than a patent, but the facts remain.

If you can argue a logical path as to why any of the audiomaster or blu cd specifications might make a difference to replay quality I'm all ears, we all are, but so far you have proposed no methodology for any improvement. Saying bigger pits = less jitter isn't an argument, you need to explain the mechanism, and you can't because none exist in exactly the same way that more accurate pit/land transitions do not improve replay quality.

Please don't back away from the discussion because you have 'run dry'.
 
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Some of these SHM CD releases sound much better than existing copies I have, but analysing them - they are different masterings so what's that got to do with what they are made of?

An exception being Fleetwood Mac's rumours where a special edition I already have is better. Again, they look different masterings.

Steve
 
Steve are you actually comparing the data on the cd's bit for bit with a file comparator? That should prove beyond reasonable doubt where different masters/mixes have been used.

As stated previously my cd of 'Ghosts in the machine' is the same as the 2003 release, but even that's a remaster of the original release. Owners of earlier cd's could easily be fooled into believing these new discs were better, rather than just containing different treatments/mixes of the same songs.
 
sq225917 said:
Steve are you actually comparing the data on the cd's bit for bit with a file comparator? That should prove beyond reasonable doubt where different masters/mixes have been used.

As stated previously my cd of 'Ghosts in the machine' is the same as the 2003 release, but even that's a remaster of the original release. Owners of earlier cd's could easily be fooled into believing these new discs were better, rather than just containing different treatments/mixes of the same songs.
Click to expand...

Yes indeed, I haven't found one like you describe "Ghosts", where they compare the same.

I have some, Donald Fagen, John Mayall, Fleetwood Mac, Tom Petty and Dire Straits SHMs, but the files compare differently, so I'm not surprised they sound different. The same is true of a Police Greatest Hits compilation - but here, my comparison is of a different compilation so the files are different again.

I agree with you that any improvements are likely to be down to masterings/mixes - but until I can get one where they measure identically, I won't be able to compare.

One thing is for sure, the SHMs sound better played as CDs or rips.

Steve
 
sq225917 said:
Are you purposefully attempting to misinterpret what i write, or do i need to explain every tiny detail to you?
"cd's wont play in players if the pit size is increased" ( of course there's some small allowance for variability written within the spec, what idiot wouldn't accept that as a given, you aren't tripping me up here, i didn't think you knew so little about the spec that i had to explain every detail).
Click to expand...

Phew,calm down, tripping you up ? As you seem to have superior knowledge, I was simplying quoteing what you had written,claiming I'm a idiot is a little rude:mad:

[/QUOTE]Your claim"Longer pits make it no easier to read", the disc has to spin faster so that the same number of longer pits passes the read head each second. 44,1000 samples worth of data 'have' to be read every second, no ifs or buts about it. There is no potential for improvement with longer pits and lands, it is just a mechanism to account for the slight variations that exists in accuracy between motors that spin the cd's. The upper and lower limits of which are "defined exactly" by the redbook spec.[/QUOTE]

Again,these are not my claims,they are Yamaha's,I thank you again for your knowledge


[/QUOTE]If you can argue a logical path as to why any of the audiomaster or blu cd specifications might make a difference to replay quality I'm all ears, we all are, but so far you have proposed no methodology for any improvement. Saying bigger pits = less jitter isn't an argument, you need to explain the mechanism, and you can't because none exist in exactly the same way that more accurate pit/land transitions do not improve replay quality

Please don't back away from the discussion because you have 'run dry'.[/QUOTE]

Back away from discussion?? Run Dry ??? Argument ?? I'm not arguing or stating anything, I'm interested in why these JPN sound better,I'm not even saying that I believe all the companies statements that I have posted on this link, and certainly you have re-educated me on certain aspects of Red Book, I'm certainly not a expert like yourself. I'm just looking to discuss matters!
 
SteveS1 said:
Yes indeed, I haven't found one like you describe "Ghosts", where they compare the same.

I have some, Donald Fagen, John Mayall, Fleetwood Mac, Tom Petty and Dire Straits SHMs, but the files compare differently, so I'm not surprised they sound different. The same is true of a Police Greatest Hits compilation - but here, my comparison is of a different compilation so the files are different again.

I agree with you that any improvements are likely to be down to masterings/mixes - but until I can get one where they measure identically, I won't be able to compare.

One thing is for sure, the SHMs sound better played as CDs or rips.

Steve
Click to expand...

A very good point,and yes you are right,some of my SHM-CD have been remastered, Styx "The Grand Illusion" is a perfect example on this.I haven't even got to mention this,what with my Red Book Education. But,I can honestly say that all my JPN disc's offer an improvement over the standard remastered CD.I've less impressed with Blu-spec,than SHM-CD. The only SHM-CD that I've got that hasn't been remastered is Styx "Paradise Theater",althought it does sound slightly better.
I've also got some of the Van morrison SHM-CD "Into The Music-Wavelength",and there is a hugh difference compaired to the standard 24/96 remastered versions,which really surprised me.

Anyway it's good to see someone else enjoying these JPN disc's.
 

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