Chris, I meant CD-Rom Media, NOT drives!
But If I was to ressurrect CD-Rom Drives, i would also look at the first generations...
So Chris and Jean Pau, how much money do you need to compete and built your drives?
Simple Question - will a (linear) one-beamer track as well as a linear three-beamer?
I have an OMS 7 to scrutinize, but the belt mechanism for the sled was ruined by some idiot, he put a gear on the motor shaft and messed up gear ratio. Have to fix this first, will take some time.
If it was linear, it will be a linear drive (nice double meaning)
To me, it would then be only a matter whether a singe or triple beam mech will be easier to set up - and suitable for multiple speed.
As far as I know, it has to be re-designed. Look at the next post
All the best,
Salar
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Hi jean-paul,
My gosh you are insulting.
Engineers design products, it's the technicians who make them work. There is some truth to that. We often wish that engineers were forced to support their designs for a couple years before moving on to the next. That would solve a lot of problems right out of the gate.
Repair guys aren't often that far removed from engineers. Many technicians come up with new products or ways of looking at things. After all, how do you think we solve engineering mistakes, by not understanding what is going on? Rethink your view on technicians jean-paul. We are merely practical engineers who don't get paid as much.
RJ 45 is a good connector for the projected use. It brings the wire closest to the connection point.
We would have had a linear tracking system (Hey! We do!!) because we understand that a CD isn't at all like a record. Anyone who suggests a swing arm and a stable platter is confused between the two formats. Stable platter should have been a clue!
Philips here had 12 divisions that didn't talk to each other, thereby replicating services needlessly. They wouldn't even share credit information. Got an account with one, doesn't matter to the others. This is a great way to go bankrupt if you ask me. I liked the people, but the company was pretty stunned. Way to picky about some things, but not the ones that mattered. We could have been spared the VAM junk and maybe had spares for the CDM-9. It at least worked well (expensive though compared to the KSS-210A transport). The CDM-9 could have survived in the marketplace had they let it. The chase for too large a return on investment ripped the innards out of that company.
-Chris
My gosh you are insulting.
Engineers design products, it's the technicians who make them work.
There is some truth to that. We often wish that engineers were forced to support their designs for a couple years before moving on to the next. That would solve a lot of problems right out of the gate.Repair guys aren't often that far removed from engineers. Many technicians come up with new products or ways of looking at things. After all, how do you think we solve engineering mistakes, by not understanding what is going on? Rethink your view on technicians jean-paul. We are merely practical engineers who don't get paid as much.
Have a look at the VAM transports then. They take the cake for cheap, yet they died (I hope). Philips is responsible for that mess too.
I was there. VHS won out because Sony was greedy with licensing fees. The high price was artificial (sad, wasn't it). Sony took that format to the grave.
RJ 45 is a good connector for the projected use. It brings the wire closest to the connection point.
Untrue.
We would have had a linear tracking system (Hey! We do!!) because we understand that a CD isn't at all like a record. Anyone who suggests a swing arm and a stable platter is confused between the two formats. Stable platter should have been a clue!
Darn! So close.
Philips here had 12 divisions that didn't talk to each other, thereby replicating services needlessly. They wouldn't even share credit information. Got an account with one, doesn't matter to the others. This is a great way to go bankrupt if you ask me. I liked the people, but the company was pretty stunned. Way to picky about some things, but not the ones that mattered. We could have been spared the VAM junk and maybe had spares for the CDM-9. It at least worked well (expensive though compared to the KSS-210A transport). The CDM-9 could have survived in the marketplace had they let it. The chase for too large a return on investment ripped the innards out of that company.
-Chris
Hi mlloyd1,
The real Mabuchi motors tend to last years, and they aren't expensive to replace.
-Chris
No replacement. Just don't use "random" or "shuffle". The copies are worse and don't even fit properly. The problem was the original spec on the disc motor. Yamaha went through three types for their motors before they got the bearings right.
The real Mabuchi motors tend to last years, and they aren't expensive to replace.
They are specially designed for each instance. I wish they would have a drop in replacement, but the space required for one is greater. The shaft tends to be larger, so you need a new disc table as well.
-Chris
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Hi Salar,
The triple beam seems to be easier to set up, but I'm not going to be 100% sure on that. The triple beam has a number of chip sets designed for it, so that might be a factor.
-Chris
What? As test discs?
Yes.
I would like to solve the issue where the belt rides on a motor shaft directly. Stupid choice, they needed an intermediate gear or pulley so they could have used a pulley at each end.
Of course, a very straight forward suggestion.
Good question. The top speed will be limited by moving part mass. The flywheel effect will work against you as well. At some point the energy required to track the CD will exceed the max recommended for reliability. I'm talking both servos (retune by speed too) and signal electronics. Hot, hot ,hot!
The triple beam seems to be easier to set up, but I'm not going to be 100% sure on that. The triple beam has a number of chip sets designed for it, so that might be a factor.
-Chris
Yes - as test discs. I assume with multispeed, warping and being off center has become an issue - so maybe, despite the faults with dyes, CD-Roms might be as even as glass discs? Just a guess.
I also remember that I had a nice regular swing in the tracking offset
of my OMS-5 Mark II when playing a CD-Rom
Speed? I assume 8x is enough to combine this transport with a ripper.
But this would be second thought in design.
@miloyd:
Here is a comparison of a Sony CDP-X5000 (brushless motor) to a
CDP-X3000 (brushed motor).
Both use the same IC for driving the motors, BA6297.
I tried to understand the principles by coloring the traces but went not very far...
Attachments
Hi Salar,
No, test discs consist of a few basic ones like Philips 5 and 5A, then I also use Pierre Verany (wish I could get a new one) two disc set. Evidently jean-paul also uses this disc. Then there are some commercial discs used to set tracking and focus gains that are specific ones. On top of that, there are your own discs, like the ones with very clean eye patterns and high reflectivity and others with various nasty problems. Those are my personal discs I use to gauge other problems like warps and eccentricity. One thing for certain is that the actual test discs cannot be copied, you must buy the actual disc. The glass disc for aligning swing arm mechanisms can not be substituted for anything else. I'll bet even the index of refraction needs to be a certain amount too. The only place I can think of that may have these would be authorized Philips warranty shops - but the main hub type shops if they have them. Maybe Philips offices that house a service department. These would likely be under an inch of dust.
Would I like one? Sure, I'd like to check the alignment of a few drives to satisfy my hunches on them. In no way would it be worth my while to have to purchase one as those transports are end-of-life.
No good will come of this ... If you want to push things, attempt to read at 2X. This may be difficult, especially when you hit disc defects.
-Chris
No, test discs consist of a few basic ones like Philips 5 and 5A, then I also use Pierre Verany (wish I could get a new one) two disc set. Evidently jean-paul also uses this disc. Then there are some commercial discs used to set tracking and focus gains that are specific ones. On top of that, there are your own discs, like the ones with very clean eye patterns and high reflectivity and others with various nasty problems. Those are my personal discs I use to gauge other problems like warps and eccentricity. One thing for certain is that the actual test discs cannot be copied, you must buy the actual disc. The glass disc for aligning swing arm mechanisms can not be substituted for anything else. I'll bet even the index of refraction needs to be a certain amount too. The only place I can think of that may have these would be authorized Philips warranty shops - but the main hub type shops if they have them. Maybe Philips offices that house a service department. These would likely be under an inch of dust.
Would I like one? Sure, I'd like to check the alignment of a few drives to satisfy my hunches on them. In no way would it be worth my while to have to purchase one as those transports are end-of-life.
Hold on there flash! Don't forget that the time constants of the transport will be way out of wack at 8X speed. You need to do two things. Change all the time constants (filters) of the servos in step with the current speed. You also have to provide very high current drive for the actuators (focus and tracking coils, motor) and prevent everything from melting down. The high speed will probably not work well. Notice that audio CDs in a CDROM drive play at 1X speeds normally? I don't think you can make a great transport and have it read at 8X. There is more than the speed to worry about. Never mind the higher frequencies the RF and EFM will be at, and the clock too.
No good will come of this ... If you want to push things, attempt to read at 2X. This may be difficult, especially when you hit disc defects.
Interesting. The brushless motor does not allow the driver IC to directly drive the motor does it?. I would think that there is a motor controller that interprets the drive signal and performs the requested actions. That is something to examine, because all the brushless motors I have seen take the error signals and power supply. All the drive electronics are internal to the motor. Maybe they found a cheaper way to do this?
-Chris
WOW, that was a big jump. From slow single speed to 8x and output to a PC for copying. Can any of the players previously mentioned do this?
A CD-ROM (Read Only Memory) is a replicated (pressed) disc containing DATA, no Dye involved. A CD-ROM will normally playback on a CD-Audio player as a single track but muted. Is this what you meant and tested?
A CD-ROM (Read Only Memory) is a replicated (pressed) disc containing DATA, no Dye involved. A CD-ROM will normally playback on a CD-Audio player as a single track but muted. Is this what you meant and tested?
Why not? Problem is the spinning noise. Without it, I think it could be gre4t.
Hi Salar,
Speaking of alternative outputs, what would people like to see? Another set of RCA jacks on a volume control? Balanced outputs off both RCA outputs? Optical and digital outputs? How about an RF (buffered eye pattern) output to monitor quality? What about a digital and optical input? My DCD-S10 has this and it is very useful - for me anyway. Anyone desire an AES output (XLR connector for digital)?
The reason I suggested digital inputs is because I am assuming that the DAC in this machine will be the best one around. The DAC PCB should also be up-gradable, like some others (Counterpoint DA-10 for example). Anyone want a 10 MHz reference oscillator input? That would over-ride the internal master clock and can be converted to whatever the system needs. The 10 MHz signal is an international standard for GPS and simple references, like an oven controlled crystal oscillator (the most stable frequency reference available over the short term). These cost less than the clock "upgrades" available and perform better. You can get a really, really good used ovenized clock for around $80 USD (HP/Agilent part), more or less. It still needs a case and power supply + connectors, but they are extremely low in phase noise. I have seen other brands of the same thing going for $25 USD, and even those represent a serious upgrade in clock quality. Just saying.
Any other suggestions to make this player upgrade friendly?
-Chris
It is true that the "blank" CD-R/CD-RW has already defined the speed and pitch, the recorder just follows along. But this is massive feature creep that can be very detrimental to the quality of the player. I would suggest that the ripping be left to either computers and DVD drives, or that it be done at 1X speed in order to optimize this new player for a function it doesn't fit. You could always rip at 1 X speed and walk away with a great copy, or simply copy via alternative output jacks to take advantage of the better error detection - correction in this player.
Speaking of alternative outputs, what would people like to see? Another set of RCA jacks on a volume control? Balanced outputs off both RCA outputs? Optical and digital outputs? How about an RF (buffered eye pattern) output to monitor quality? What about a digital and optical input? My DCD-S10 has this and it is very useful - for me anyway. Anyone desire an AES output (XLR connector for digital)?
The reason I suggested digital inputs is because I am assuming that the DAC in this machine will be the best one around. The DAC PCB should also be up-gradable, like some others (Counterpoint DA-10 for example). Anyone want a 10 MHz reference oscillator input? That would over-ride the internal master clock and can be converted to whatever the system needs. The 10 MHz signal is an international standard for GPS and simple references, like an oven controlled crystal oscillator (the most stable frequency reference available over the short term). These cost less than the clock "upgrades" available and perform better. You can get a really, really good used ovenized clock for around $80 USD (HP/Agilent part), more or less. It still needs a case and power supply + connectors, but they are extremely low in phase noise. I have seen other brands of the same thing going for $25 USD, and even those represent a serious upgrade in clock quality. Just saying.
Any other suggestions to make this player upgrade friendly?
-Chris
Did all this (6 inputs) with my Nakamichi - OMS5II and built
in a Buffalo II, to my ears one of the best.
Thus the Nak serves as Player and Dac, player circuitry
can be switched off.
Only AES and external clock are missing
Will definately do it with the new one plus
all the means to make it a good DAC.
in a Buffalo II, to my ears one of the best.
Thus the Nak serves as Player and Dac, player circuitry
can be switched off.
Only AES and external clock are missing
Will definately do it with the new one plus
all the means to make it a good DAC.
Hi Salar,
Looks like we think along the same lines. Yes, as good as the existing setup sounds, it's only a 14 bit DAC. I'd love to see a PCM-1702 or 1704 in there! What a perfect marriage that would be.
A DDS circuit can take the 10 MHz reference and create whatever frequency you need.
-Chris
Looks like we think along the same lines. Yes, as good as the existing setup sounds, it's only a 14 bit DAC. I'd love to see a PCM-1702 or 1704 in there! What a perfect marriage that would be.
A DDS circuit can take the 10 MHz reference and create whatever frequency you need.
-Chris
No - Buffalo II is an ESs Sabre 9018 32/192kHz DAC.
http://www.diyaudio.com/forums/twisted-pear/219921-buffalo-iii-se.html
BTW, the original PCM 56 in the Nak I replaced with the Buffalo was 16bit/176.
Here are pictures of the mod:
http://www.diyaudio.com/forums/twisted-pear/219921-buffalo-iii-se.html
BTW, the original PCM 56 in the Nak I replaced with the Buffalo was 16bit/176.
Here are pictures of the mod:
Attachments
Hi Salar,
How did you convert the digital audio stream to a newer type?
When I do my mod, I think I would want to put that much stuff in an external box. The clock and LR CLK and audio stream would be buffered and run into the outboard box. There is already a lot going on inside an OMS-7.
You can reply to this via normal email if you want. I had almost resigned myself to buffering the eye pattern and sending it into a complete chip set. I would need the mute lines in that case as well.
-Chris
Edit: How did you make the display blue? The buttons are easy - blue LEDs.
How did you convert the digital audio stream to a newer type?
When I do my mod, I think I would want to put that much stuff in an external box. The clock and LR CLK and audio stream would be buffered and run into the outboard box. There is already a lot going on inside an OMS-7.
You can reply to this via normal email if you want. I had almost resigned myself to buffering the eye pattern and sending it into a complete chip set. I would need the mute lines in that case as well.
-Chris
Edit: How did you make the display blue? The buttons are easy - blue LEDs.
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I am Sorry, wrong naming:
I meant DIT4096
http://www.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=dit4096&fileType=pdf
All the best, Salar
I meant DIT4096
http://www.ti.com/general/docs/lit/getliterature.tsp?genericPartNumber=dit4096&fileType=pdf
All the best, Salar