I don't know what the Japanese magazine says about this "tuning". Imo, it is normal to always try to find possible improvement especially in high cost products. It is just that it cannot be a "big" improvement as you might have expected or read...
OK, I'll bite...
Browsed two japanese websites ( and ). Here are statements in Japanese:
メカニズム部にはプロ用CDプレイヤーにも採用されたCDM-1メカをチューンナップして採用しています。
従来メカニズム内にマウントされていたレーザーシグナル用プリアンプを分離独立させたことで、回転系の微振動からプリアンプ回路を解放し、さらに回路そのものも、大規模で音質的に追求されています。
Translated: A mechanism part is adopted by tune up the CDM-1 mechanism that has been adopted for professional CD player.
By spun off the laser signal for the preamplifier, which has been mounted in the conventional mechanism, to release the preamplifier circuit from the slight vibration of the rotation system, further circuit itself has also been pursued sound quality on a large scale.
(Marantz CDƒvƒŒƒCƒ„�[CD-94‚ÌŽd—l ƒ}ƒ‰ƒ“ƒc)
CDドライブメカに採用されているCDM-1メカをチューンアップして搭載。補強リブの追加による剛性向上と、レーザーシグナル用プリアンプの分離独立設置により、振動による音質劣化の可能性を排除しています
Translated: Equipped to tune up the CDM-1 mechanism, which has been adopted in the CD drive mechanism. And rigidity improved by the addition of the reinforcing ribs, by separate and independent installation of the pre-amplifier for the laser signal, we can not rule out the possibility of sound quality degradation caused by vibration
(–¼�ì‰f‰æ�E—mŠy–¼”ÕƒKƒCƒh�Eƒ}ƒ‰ƒ“ƒc CD-94 Limited)
It seems the main tuning-up improvement is to move the laser preamp from the "lump" PCB (to external PCB, which is the servo board) to avoid degradation due to vibration. From the web pictures of tuned CDM-1, the preamp is strangely still on the lump CDM-1 PCB, but I think it is somehow bypassed?? (You have to track the small pcb layout). The new laser preamp (along with the supply) is now on the small daughter board on top of the main servo board. It's a much better discrete circuit using discrete components and basic opamps.
If you're curious as to where the "standard" or old laser preamp is, it is the pot and dual opamp (NE532/LM358) on the right side of the lump PCB. I attached the circuit of old CDM to show how laser diodes are connected to the supply/preamp.
The other circuits on the lump PCB are still used. They are:
From photo diodes flexible:
(1) The discrete circuit on the micro board is the HF preamp (EFM)
(2) The quad opamp (NE5514), the focus offset pot, the single opamp (LM741), the focus error pot, qre to pre process the focus error from the photo diodes
From laser diodes and focal coil flexible:
(1) The laser preamp is bypassed (I think)
(2) The focus coils supply is never processed on the lump board (bypass).
Attachments
Sorry, I was referring to the feed/sled/tracking motor. My point was, why not a CD player use the same techniques, but you mentioned about noise, so may be there are trade-offs there.
I have tried to relate the CDROM speed with sound quality (of course it was not a credible listening test, but I know I have good ears anyway 😀).
My intuition was that the best sound was with medium speed. To rationale this, I thought:
By using high speed and optimum RAM size, correction can be optimized. But the speed also create vibration which causes error before correction (BLER) etc.
So the optimum condition should be somewhere in the middle (depends on RAM size and other conditions).
Best result I get is using 1x Speed in MASTER MODE & carbon CD-R & F1 Yamaha burner and still recording dependent to invert the phase.
Hp
No need to do listening tests. Use NERO Discspeed with the right CD Drive and you can measure the amount of errors.
Hi Jon,
You seem to have a good understanding of the issues.
One thing I will point out is that if you can keep the DAC local to the machine, you do not have to combine the three signals into the single serial data stream, and therefore will have less jitter automatically. If the signals are made available with a universal mounting area, you can have your pick of many different DAC boards. You can also then have your choice of signal buffers too. This would more than satisfy most people out there.
Trays / drawers.
These devices handle the CD far more gently than your own hand. I would highly recommend that a loading tray be used. They are not complicated and can operate very smoothly. Manual top loading machines tend to scratch CDs when the inevitable happens and the CD drops inside or outside the machine. The manual puck placement is another like story. Most depend on a twist latch or similar locking mechanism.
Most good CD transports will last a very long time with minimal maintenance. They will always need cleaning / lubrication on intervals. Hair will always be found inside most machines (and other things). The newer laser heads will very probably last as long as the rest of the machine. Heads were not the major failure point anyway. Motors were, but the very robust motor used in the Nakamichi OMS-5/7 is still running in most machines. That makes them ancient.
I do believe that an "archival" type transport is what we need. Something built to last with internal options to tailor the unit to most people's tastes. If wanted, we can even provide an output to be used with odd buffers (like tube types, or really high end diamond buffers). I think this is where the market will be found. The same model differing in options that can be retrofit later even, year after year. Physics doesn't change the rules, so why do we need to change the model?
-Chris
You seem to have a good understanding of the issues.
One thing I will point out is that if you can keep the DAC local to the machine, you do not have to combine the three signals into the single serial data stream, and therefore will have less jitter automatically. If the signals are made available with a universal mounting area, you can have your pick of many different DAC boards. You can also then have your choice of signal buffers too. This would more than satisfy most people out there.
Trays / drawers.
These devices handle the CD far more gently than your own hand. I would highly recommend that a loading tray be used. They are not complicated and can operate very smoothly. Manual top loading machines tend to scratch CDs when the inevitable happens and the CD drops inside or outside the machine. The manual puck placement is another like story. Most depend on a twist latch or similar locking mechanism.
Most good CD transports will last a very long time with minimal maintenance. They will always need cleaning / lubrication on intervals. Hair will always be found inside most machines (and other things). The newer laser heads will very probably last as long as the rest of the machine. Heads were not the major failure point anyway. Motors were, but the very robust motor used in the Nakamichi OMS-5/7 is still running in most machines. That makes them ancient.
I do believe that an "archival" type transport is what we need. Something built to last with internal options to tailor the unit to most people's tastes. If wanted, we can even provide an output to be used with odd buffers (like tube types, or really high end diamond buffers). I think this is where the market will be found. The same model differing in options that can be retrofit later even, year after year. Physics doesn't change the rules, so why do we need to change the model?
-Chris
Hi Mark,
I am skeptical of this because any program will report on what it is sent after the signal has passed through the DSP for error correction. Not unless the software in question has access to the C1, C2 error flags (and from there can generate the Ex codes you were talking about earlier). You need to have access to the raw serial data stream right after the EFM signal is demodulated. The only way I can assess errors in home CD players is to have access to those two Cs level flags in hardware. I'm not saying this can't be done, I just don't know and have learned to be very careful of where the signals come from in order to assess how valid the numbers would be.
The source of my concerns is that data coming from the DSP is valid from a format and value boundary perspective, not from a disc read error perspective. I don't believe that the data is available to be read until the DSP is finished processing the data. What you might possibly be reading is a "data invalid" flag test point to signal any following circuitry that the present data, although format correct, has an invalid payload.
-Chris
Will this work with audio CDs, not data CDs like MP3 and other digital formats?
I am skeptical of this because any program will report on what it is sent after the signal has passed through the DSP for error correction. Not unless the software in question has access to the C1, C2 error flags (and from there can generate the Ex codes you were talking about earlier). You need to have access to the raw serial data stream right after the EFM signal is demodulated. The only way I can assess errors in home CD players is to have access to those two Cs level flags in hardware. I'm not saying this can't be done, I just don't know and have learned to be very careful of where the signals come from in order to assess how valid the numbers would be.
The source of my concerns is that data coming from the DSP is valid from a format and value boundary perspective, not from a disc read error perspective. I don't believe that the data is available to be read until the DSP is finished processing the data. What you might possibly be reading is a "data invalid" flag test point to signal any following circuitry that the present data, although format correct, has an invalid payload.
-Chris
It will work with all CD (and DVD) formats. The error correction data is generated during the process of C1/C2 correction and with ROM drives it is used internally for setting the read strategy. The error data can then be passed on to the PC. All this takes place before the DSP.
Hi Mark,
That's really cool! Good to know. Now this is useful.
What drives will this work with?
Thanks Mark, -Chris
That's really cool! Good to know. Now this is useful.
What drives will this work with?
Thanks Mark, -Chris
Hi Mark,
I'm thinking that if I was making one I'd make it so it would be able to read more than once because speeding the disc up sometimes introduces read errors that aren't there at lesser speeds (and vice-versa too, IME). I'm wondering why other manufacturers didn't think that way...
Well, I can see where you are trying to go with this line of thought but, believe it or not, my response is 'yes'. My reasoning is that in our case we are wanting to deal with a media format from the '80's.
Jon.
I'm thinking that if I was making one I'd make it so it would be able to read more than once because speeding the disc up sometimes introduces read errors that aren't there at lesser speeds (and vice-versa too, IME). I'm wondering why other manufacturers didn't think that way...
Well, I can see where you are trying to go with this line of thought but, believe it or not, my response is 'yes'. My reasoning is that in our case we are wanting to deal with a media format from the '80's.
Jon.
Hi Mark,
There are times when progress is not to our benefit. The machines of the 80's and early 90's represented the pinnacle of quality for the CD player. There was a genuine effort to make the best machines on the market. What followed was a decades long cost cutting exercise. They eliminated many adjustments, especially the mechanical ones. Everything was done to cut costs and to produce a very poor quality product from the standpoint of the higher end market. For those who would buy the lowest cost items, they had nowhere to go but up. So the low quality products disappeared for the most part, replaced by a poor quality, but better product than they were used to. They won (if you can call that winning).
In the end, the entire market succeeded in taking a profitable business and turned it into a commodity market item. The computer industry crashed first that way, then they turned their attention to the audio field and destroyed that industry too. Right now the telecommunications industry is past half way along in this same process.
Guess who ends up the loser in all this? You. The consumer is the one who ultimately suffers. Quality is a rare thing and getting more rare.
I used to look at the audio industry and say, "well that's it, they've hit bottom". I expected the industry to have a die-off, then recover by going back to making good products again (that is where profit lives). But nope, it just kept crashing shedding businesses all the way down. It's still getting worse every year. I keep wondering just how bad it has to get before waking up.
So who wants a product constructed like they did in the 1980's, but with today's technology ('cause that is what we are trying to do here) - ME! Me and every other person who enjoys listening to good music on a good system. The same can be said of the turntable and all other aspects of a home audio system. We all want the stuff that was worth buying, and that will last.
-Chris
There are times when progress is not to our benefit. The machines of the 80's and early 90's represented the pinnacle of quality for the CD player. There was a genuine effort to make the best machines on the market. What followed was a decades long cost cutting exercise. They eliminated many adjustments, especially the mechanical ones. Everything was done to cut costs and to produce a very poor quality product from the standpoint of the higher end market. For those who would buy the lowest cost items, they had nowhere to go but up. So the low quality products disappeared for the most part, replaced by a poor quality, but better product than they were used to. They won (if you can call that winning).
In the end, the entire market succeeded in taking a profitable business and turned it into a commodity market item. The computer industry crashed first that way, then they turned their attention to the audio field and destroyed that industry too. Right now the telecommunications industry is past half way along in this same process.
Guess who ends up the loser in all this? You. The consumer is the one who ultimately suffers. Quality is a rare thing and getting more rare.
I used to look at the audio industry and say, "well that's it, they've hit bottom". I expected the industry to have a die-off, then recover by going back to making good products again (that is where profit lives). But nope, it just kept crashing shedding businesses all the way down. It's still getting worse every year. I keep wondering just how bad it has to get before waking up.
So who wants a product constructed like they did in the 1980's, but with today's technology ('cause that is what we are trying to do here) - ME! Me and every other person who enjoys listening to good music on a good system. The same can be said of the turntable and all other aspects of a home audio system. We all want the stuff that was worth buying, and that will last.
-Chris
AFAIK, this is a normal algorithm. That's why I mentioned that RAM to some extent can be beneficial. With RAM the music is not played in "real time". If you stop the disc spin with your finger, the music will still play uninterrupted because the data is in memory/buffer.
So the reading and correction can be programmed ahead of streaming. The spindle motor can run more than one cycle (reading the same block or frame) in order to recover error.
Hi Jay,
That's exactly how the Creek unit works. The same for any of the others that use a computer CDROM drive.
-Chris
That's exactly how the Creek unit works. The same for any of the others that use a computer CDROM drive.
-Chris
The benefit is always for those who make progress.
You cannot change marketing theory. There is place and products for those who wants the best products at any price, but profit comes from leveraging the business. The majority is poor, that's why it is hard to overcome the psychology that the poor doesn't care about the quality as long as they have the money to buy. Even worse, they want a $2 product that last for a year (equal to $4/2yr) than $3 that last for 2 year. There are many psychology involved, which is of Marketing concern.
May be we are on this thread that have to wake up. We know who is the leader and where the direction is going. Instead of going back we should go faster, anticipating, with quality/technology/innovation in mind (coz we have different agenda with the leader).
CDROMs use protocols used by computers so it is a lot easier to write program that read whatever in the memory, without hardware change. With regular CDP which also run at 1x ('real time') this is not so.
C1/C2 is a standard (but who is enforcing?) for firmware and optical drives but how it is implemented could be different.
C1/C2 is "flagged" in DSP level to be used with CIRC and interpolation circuitry. Software should be written to red those "flags". Inaccuracy can happen, depends on the program and how the DSP/chip "reports" those C1/C2.
The result of this typical software has been shown by Mark when he showed the report for the 50 TDK discs before. Skeptical? I think, may be we are barking on the wrong tree...
For us, me especially, there are main objectives to be addressed:
(1) How things will affect sound (audible effect)
(2) Durability of the transport
(3) Convenience of the transport operation
Those objectives, when analysed critically, even lead me to believe that CD is not the way to go.
Hi Chris,
Yes, that makes sense. Only comment I have is that to me the high end player products of the well known household brands don't sound as good as an average transport fed into a reasonably decent external DAC regardless of whatever length of cheap cable I use for hook-up. OK, that's subjective I know. But don't most half decent external DACs re-clock the signal anyway?
Actually, it's not really just the DAC (chip) on it's own, it's the implimentation. So perhaps wrong to say the DAC itself is good or bad, but you know what I mean.
I'd have concerns that if doesn't output S/Pdif that might alienate about 99% of the potential user base.
Yes, that makes sense. Only comment I have is that to me the high end player products of the well known household brands don't sound as good as an average transport fed into a reasonably decent external DAC regardless of whatever length of cheap cable I use for hook-up. OK, that's subjective I know. But don't most half decent external DACs re-clock the signal anyway?
Actually, it's not really just the DAC (chip) on it's own, it's the implimentation. So perhaps wrong to say the DAC itself is good or bad, but you know what I mean.
I'd have concerns that if doesn't output S/Pdif that might alienate about 99% of the potential user base.
Can C1/C2 effect sound? The results of every player without E32 must be the same.
The reality is that even the best of the old drives are struggling to get the job done. They are working at their maximum potential.
Don't ask me to predict the future of audio. When the consumer was given the option of SACD, they all chose MP3.
Would you really purchase a car without airbags, fuel injection or GPS?
The reality is that even the best of the old drives are struggling to get the job done. They are working at their maximum potential.
Don't ask me to predict the future of audio. When the consumer was given the option of SACD, they all chose MP3.
Would you really purchase a car without airbags, fuel injection or GPS?
Isn't the point: when do enough C1 errors become C2 errors and when do enough C2 errors become E32 errors and when do enough E32 errors become obviously noticable and induce players to 'skip' in the various ways they do?
Or, if I can put this in context, when a CD which I know can generate errors including occasional E32 errors is played in a CD player the audible and physical result (and the S/Pdif output) will vary slightly each time it is played a) in the same CD player and b) across two identical model CD players.
In the same way, the same CD will give a slightly different error report each time when 'tested' in the same CD-ROM drive using the same test.
I believe they call them 'classic cars' - there's quite a large following by all accounts. ;-)
Jon.
The limits are very clear and set in the Redbook. BLER<220 and E32=0. The problem is that the player leaves you guessing at what levels of error correction is active. This is why I suggested monitoring the error correction at the beginning of this thread.
If they were "new" they would not be "classic". Anyone for a new Opel kadett E? (Vauxhall Astra Mark 2 in the UK)
If they were "new" they would not be "classic". Anyone for a new Opel kadett E? (Vauxhall Astra Mark 2 in the UK)
Hi Jon,
All external DACs reclock. There is not clock transmitted, it has to be regenerated from the data stream. Jitter is a problem here. There are external "re-clockers" available to address that issue. Then they resend the data serially again. Essentially accomplishing zero but reducing your bank balance. Shockers.
Hi Mark,
Many players are lacking in performance to a point where they barely play CDs. Some were actually only 12 bit machines (early discman clones)! The redbook standards apply to the media only anyway, and there are many that do not measure up to those "rules". Therefore, no assumptions can be made about media or machine.
I really wish you wouldn't make comments like this. I was in at the beginning, some machines didn't work that well - true. But there were many that had exceptional performance. It took the D to A process many years to catch up, the same is true of the digital error correction. That took a while. It was therefore necessary for those early CD players to perform next to perfectly. Surely you can appreciate that, no safety net to save the day when digital errors became a problem. This is why the eye pattern was so darned important. It still is today, even when error correction and concealment are so good. Protection is best left for times when it's needed. Not something that you should depend on to make a crappy machine sound good.
I can predict the next (permanent) thing. It will be music either for download, or supplied on a non-mechanical memory device. That is all a CD really is, a storage device. We will finally move to real memory to eliminate all mechanical wearout / alignment issues. However, not everything will be re-released again. We are stuck with turntables (I like mine), tape machines (I like mine) and CD players. From there we can move the information onto the prevailing memory storage technology. Or, you can opt to lose your musical heritage and abandon your old favorites and stick to the current music. A person without a musical past at all. That is a valid choice and yet another sign that the audio industry has abused its customer base past the point where they could deal with it.
Either way, Mark, you will be out of a job soon enough. You had better learn what is going to be out next and position yourself to be included. Me? I'm an old repair guy who will always have customers. I'll learn what is next though. It's interesting.
-Chris 🙂
All external DACs reclock. There is not clock transmitted, it has to be regenerated from the data stream. Jitter is a problem here. There are external "re-clockers" available to address that issue. Then they resend the data serially again. Essentially accomplishing zero but reducing your bank balance. Shockers.
Hi Mark,
Many players are lacking in performance to a point where they barely play CDs. Some were actually only 12 bit machines (early discman clones)! The redbook standards apply to the media only anyway, and there are many that do not measure up to those "rules". Therefore, no assumptions can be made about media or machine.
Completely untrue.
I really wish you wouldn't make comments like this. I was in at the beginning, some machines didn't work that well - true. But there were many that had exceptional performance. It took the D to A process many years to catch up, the same is true of the digital error correction. That took a while. It was therefore necessary for those early CD players to perform next to perfectly. Surely you can appreciate that, no safety net to save the day when digital errors became a problem. This is why the eye pattern was so darned important. It still is today, even when error correction and concealment are so good. Protection is best left for times when it's needed. Not something that you should depend on to make a crappy machine sound good.
The growing minority is looking for good products to buy, MP3s are something the kids are more invested in. This is a sign that the population has given up on the audio industry. From what I see, they are justified in doing so when any clear reasons to attempt to get a good sounding system together is so difficult.
I can predict the next (permanent) thing. It will be music either for download, or supplied on a non-mechanical memory device. That is all a CD really is, a storage device. We will finally move to real memory to eliminate all mechanical wearout / alignment issues. However, not everything will be re-released again. We are stuck with turntables (I like mine), tape machines (I like mine) and CD players. From there we can move the information onto the prevailing memory storage technology. Or, you can opt to lose your musical heritage and abandon your old favorites and stick to the current music. A person without a musical past at all. That is a valid choice and yet another sign that the audio industry has abused its customer base past the point where they could deal with it.
Either way, Mark, you will be out of a job soon enough. You had better learn what is going to be out next and position yourself to be included. Me? I'm an old repair guy who will always have customers. I'll learn what is next though. It's interesting.
-Chris 🙂
Hi Jay,
The main issue is this. Can we create the one CD player that will be reliable and possess the quality required to extract the information from CDs with as little data loss as possible. I have a very clear picture of what that looks like. Old mechanical technology married to newer error correction technology and hopefully no need to conceal errors more serious than the C1 stage to deal with. But if it all goes pear shaped, it's nice to have a great error concealment stage in your back pocket. We have already had our peak performance realized for removing data from a CD. We have fallen a great distance from those standards and depend on software to fool us into thinking everything is okay.
-Chris
My point exactly.
Yes, absolutely.
The problem with that is that it is an internal thing. The memory used is only for the music data included with status information , like the C flags. You can only read these is you have access to the data stream at this point (you don't). The only flag you might have access to is the C2 flag (all is lost).
There really is no excuse for any interpretation problems between software or hardware. Everything is clearly defined. Can a chip maker mess this up? Absolutely.
I agree. However, we are stuck with it if we wish to access music we have already bought license for.
The main issue is this. Can we create the one CD player that will be reliable and possess the quality required to extract the information from CDs with as little data loss as possible. I have a very clear picture of what that looks like. Old mechanical technology married to newer error correction technology and hopefully no need to conceal errors more serious than the C1 stage to deal with. But if it all goes pear shaped, it's nice to have a great error concealment stage in your back pocket. We have already had our peak performance realized for removing data from a CD. We have fallen a great distance from those standards and depend on software to fool us into thinking everything is okay.
-Chris