Re: late to the question.
Nanook, you are right the Pioneer mech's do seam to sound better, than some others, yes there was a problem with the odd lens falling out but it wasn't due to heat, the problem was that Pioneer use a water soluble glue to stick them in, so as not to cloud the back of the lens with solvent based glue, what happened was that in high humidity areas the water based glue softened just like wall paper glue will let go in high humidity, this was rectified later with a better glue, were you live "windy dusty" sound like you will not have any problem. If it does , just clean it up and stick it back with the tiniest drop of super glue on the edge only and make sure it seats back down into the housing.
As for the reliability of the mech, sure some models like the cheaper 701 801 were built to a price, and weren't as robust, just like all other brands on the market, but the upper end models are bullet proof, my old PD77 (PD75) that I bought new in the late 80's early 90's has seen now out 3 new lasers that's how much use it's had, nearly 20 years old and the mech (PIC) is still going strong, sure it is a pain to set up 13 adjustments from scratch if your keen to start from the beginning.
I love the Pioneer Stable Platters but I have a small preference for the Teac VRDS.s And when re-clocked with a good clock can't be beaten easily for sound quality.
Cheers George
Nanook said:
Nanook, you are right the Pioneer mech's do seam to sound better, than some others, yes there was a problem with the odd lens falling out but it wasn't due to heat, the problem was that Pioneer use a water soluble glue to stick them in, so as not to cloud the back of the lens with solvent based glue, what happened was that in high humidity areas the water based glue softened just like wall paper glue will let go in high humidity, this was rectified later with a better glue, were you live "windy dusty" sound like you will not have any problem. If it does , just clean it up and stick it back with the tiniest drop of super glue on the edge only and make sure it seats back down into the housing.
As for the reliability of the mech, sure some models like the cheaper 701 801 were built to a price, and weren't as robust, just like all other brands on the market, but the upper end models are bullet proof, my old PD77 (PD75) that I bought new in the late 80's early 90's has seen now out 3 new lasers that's how much use it's had, nearly 20 years old and the mech (PIC) is still going strong, sure it is a pain to set up 13 adjustments from scratch if your keen to start from the beginning.
I love the Pioneer Stable Platters but I have a small preference for the Teac VRDS.s And when re-clocked with a good clock can't be beaten easily for sound quality.
Cheers George
Attachments
Chris, one must have bitten you on the butt or something when you were a kid for you to have such hatred for such fine transports.
Wadia, Krell, and a couple of other so called high end manufacturers didn't use them for nothing in their top transports, they were tree times the price of anything else around at the time, so it wasn't cost saving that made them use them, they didn't advertise the fact that they used them, so it could maybe have been that they may have sounded better than anything else, they could of saved a fortune by using Philips or Sony ones. The guys that design these very good cd players/transports I'm sure are a few rungs up the techincal ladder than you.
I'm over this, you have a one man vendetta against Pioneer/Teac transport mechs, that you have yet to justify to anyone.
Cheer George
Wadia, Krell, and a couple of other so called high end manufacturers didn't use them for nothing in their top transports, they were tree times the price of anything else around at the time, so it wasn't cost saving that made them use them, they didn't advertise the fact that they used them, so it could maybe have been that they may have sounded better than anything else, they could of saved a fortune by using Philips or Sony ones. The guys that design these very good cd players/transports I'm sure are a few rungs up the techincal ladder than you.
I'm over this, you have a one man vendetta against Pioneer/Teac transport mechs, that you have yet to justify to anyone.
Cheer George
georgehifi said:
Make that at least a two man vendetta
He has explained the weaknesses as pointed out earlier pretty well, and they match my experience 100%.
On a different note, if anybody gets superglue even near any of my optical stuff, they're in trouble. It damages the lens instantly.
Magura
On the side track.
Is this a good transport? No complain about the price but it got to worth spending many hours of building it. They have a high end version that uses better MUSE cap, Wima, Dale resistor etc but transport is the same.
Translate from Chinese.
http://translate.google.com/transla...&hl=en&ie=UTF-8&oe=UTF-8&prev=/language_tools
Is this a good transport? No complain about the price but it got to worth spending many hours of building it. They have a high end version that uses better MUSE cap, Wima, Dale resistor etc but transport is the same.
Translate from Chinese.
http://translate.google.com/transla...&hl=en&ie=UTF-8&oe=UTF-8&prev=/language_tools
Hello SamSamL said:
I have no direct experience with that transport but I would advise to replace the 16.9344M TCXO. Inside it you'll probably find the ICS525-01 (see attach.) and a standard 19.8MHz oscillator used as reference. No matter how you look at it its not a low jitter clock. Guido may offer an explanation (and I'm sure a better alternative also)!
What I like about the layout of the main pcb: they use GND vias around the input rf signals, clocks and the spdif out
phimor said:
Seriously, as a long time tech, you have a perspective on this few would match, so Im really interested in your dismissal of the Philips swing arm mechs.
Putting aside the political problem, of no support, and the obvious change in policy with the CDM12, I would offer the observation that the CDM0 and CDM1 are mechanically very sound, and some would say 'over engineered'.
Certainly on the face of it, they combine a simple operational principle (single beam) with an elegant mechanism with two moving parts (motor and arm). Both appear to offer long time serviceability, without maintenance.
Those two series CDM0 and CDM1 are much sturdier than the later swing arms - cdm2 to 4 (and that horror linear thing).
Anecdotally, I have collected over 10 CDM0/1 players (for reasons that are too boring to discuss), and all the drives work perfectly after 20 to 25 years of abuse....
Same over here. I rarely have had to replace a laser because it was totally wornout. Cleaning was the remedy. Since I had a stock of CDM4s I replaced them now and then in my CDM4 equipped cdplayers to be sure the cdplayer would function more years.
CDM1 Mk2 is one of the most reliable of that series.
Anatech has seen many cdplayers on a professional base so I trust his experience but IMO Sony heads fail much too often. As an example I can dig up KSS213 and that dreadful mech on SACD players. Same story for the falling lenses with Pioneer.
Much of the older Japanese linear mechanisms were wonderful engineered but with poor implemented electronics or only average sound quality. I recall Pioneer PD8500 which had a very fine transport.
Hello Anatech and all,
Wondered if you have any evidence/experience of how atmospheric pollution effects the internal optics.I have seen N.O.S. (new old stock) parts that are less than pristine.
As for cheap spindle motors, I always put a small dab of grease on the upper bearing, pity the lower one is innacessible.
-Mooly-
Wondered if you have any evidence/experience of how atmospheric pollution effects the internal optics.I have seen N.O.S. (new old stock) parts that are less than pristine.
As for cheap spindle motors, I always put a small dab of grease on the upper bearing, pity the lower one is innacessible.
-Mooly-
Hi Mooly,
Cooking oils and smoke can coat the internal optics. I'm sure that atmospheric pollution could affect some also. The Sony KSS-123 types have a center post that gets gummy and causes focus issues sometimes.
Hi jean-paul,
Hi mlloyd1,
Hi George,
High end manufacturers use the cheapest mech they can. Sony overcharges for their transports and NEC made the nicest ones I have seen. The current Philips are often the least expensive and that is why you see them in high end model CD players. What the general public thinks of a product has far more to do with what is used than actual quality.
I don't hate Teac's transport. I just mentioned that it is starting behind the 8-ball. It is at least made well. We did have problems in the beginning with bearings though. Remember, I serviced the early ones under warranty. I know a lot about them and the reality of the design.
George, please do us all a favour and actually learn something about what you are doing. You are not doing your customers any favours, or yourself. You do seem to be easily swayed by the high end media, more than knowledge. Did you ever take physics in school? If so, apply your lessons.
-Chris
Cooking oils and smoke can coat the internal optics. I'm sure that atmospheric pollution could affect some also. The Sony KSS-123 types have a center post that gets gummy and causes focus issues sometimes.
Hi jean-paul,
Any of the newer designs made cheaply seem to be a problem. Most Sony heads are replaced when the disc motor is at fault.
Whatever Revox used had lens suspension problems. IT was all diecast, but I can't exactly remember which model Philips were used.
Hi mlloyd1,
Avoid using the "random" feature. That would be the "DIE" button.
Hi George,
Nope. I made money on these hand over fist.
Hmmm. You are the master at run-on sentences!
High end manufacturers use the cheapest mech they can. Sony overcharges for their transports and NEC made the nicest ones I have seen. The current Philips are often the least expensive and that is why you see them in high end model CD players. What the general public thinks of a product has far more to do with what is used than actual quality.
I don't hate Teac's transport. I just mentioned that it is starting behind the 8-ball. It is at least made well. We did have problems in the beginning with bearings though. Remember, I serviced the early ones under warranty. I know a lot about them and the reality of the design.
George, please do us all a favour and actually learn something about what you are doing. You are not doing your customers any favours, or yourself. You do seem to be easily swayed by the high end media, more than knowledge. Did you ever take physics in school? If so, apply your lessons.
-Chris
?sidiy said:
Hello Sam
I have no direct experience with that transport but I would advise to replace the 16.9344M TCXO. Inside it you'll probably find the ICS525-01 (see attach.) and a standard 19.8MHz oscillator used as reference. No matter how you look at it its not a low jitter clock. Guido may offer an explanation (and I'm sure a better alternative also)!
What I like about the layout of the main pcb: they use GND vias around the input rf signals, clocks and the spdif out
Hi
I don't know this particular clock (but if it is based upon ICS525-01: throw away as far as possible). All the Chinese seem to be in love with low ppm figures. Chinese clocks I measured and auditioned so far are not convincing me.......
all the best
Guido
anatech said:
georgehifi said:
Chris and George, I for sure would like to see a more friendly tone when adressing to other forum members whether they have knowledge on some subject or not. It is not good to read for others nor will it do any good to the forum. This especially counts for mods, better be a role model instead of letting yourself get dragged into mudslinging.
Hi Anatech, Guido, Rfbrw and all...
Quote from Guido:
What do you think about the magnetic clamp mechanism, which in the case of CDpro is powerful, potentially affecting EFM signal?
Have you tested this?
I was pointed to that on a CDpro thread and I made one test that sort of convinced me: listening ABAB a CD that had a tight fit to the center "cone" to such extent that it did not need the clamp. Listening without the magnetic clamp sounds really better.
I value your opinion a lot.
Thanks
M
Quote from Guido:
What do you think about the magnetic clamp mechanism, which in the case of CDpro is powerful, potentially affecting EFM signal?
Have you tested this?
I was pointed to that on a CDpro thread and I made one test that sort of convinced me: listening ABAB a CD that had a tight fit to the center "cone" to such extent that it did not need the clamp. Listening without the magnetic clamp sounds really better.
I value your opinion a lot.
Thanks
M
Hi maxlorenz,
A magnetic clamp is a significant improvement over any other clamp mechanism. You eliminate a bearing surface that will wear out and decouple better from vibrations in the chassis.
A magnetic field will not affect the laser in any significant way. The biggest issue might be the focus and tracking coils in the head. If this were the case you could easily see in in the eye pattern.
I should make an important point here. Nothing you can do with markers or <green> LEDs will affect the sound quality. We are dealing with information split up evenly in an RF waveform. You can not affect just the bass or highs in any way. The only one thing you can do is add digital errors. Also, those stick on thingies for CD's only increase the mass. This throws off the tuning of the servos, resulting in more digital errors. The very best thing you can do is keep them clean and unscratched and simply play them. Don't mess with anything that the designer didn't design into the system.
-Chris
A magnetic clamp is a significant improvement over any other clamp mechanism. You eliminate a bearing surface that will wear out and decouple better from vibrations in the chassis.
A magnetic field will not affect the laser in any significant way. The biggest issue might be the focus and tracking coils in the head. If this were the case you could easily see in in the eye pattern.
I should make an important point here. Nothing you can do with markers or <green> LEDs will affect the sound quality. We are dealing with information split up evenly in an RF waveform. You can not affect just the bass or highs in any way. The only one thing you can do is add digital errors. Also, those stick on thingies for CD's only increase the mass. This throws off the tuning of the servos, resulting in more digital errors. The very best thing you can do is keep them clean and unscratched and simply play them. Don't mess with anything that the designer didn't design into the system.
-Chris
Hi maxlorenz,
Most magnetic clamp systems I've seen are already about as lightweight as you can get them. I'm talking about a little plastic clamper that has a thin metal plate and a magnet. The mass is almost 100% magnet.
Don't forget that it has to keep the CD from sliding on the disc table. So a strong clamping force is the best here.
I don't believe the magnetic clamp will affect anything in the CD playback system. You would see this as a change in the eye pattern. If something will affect the sound in any way, it will be seen as error flags or in worse cases, degraded eye patterns.
-Chris
Most magnetic clamp systems I've seen are already about as lightweight as you can get them. I'm talking about a little plastic clamper that has a thin metal plate and a magnet. The mass is almost 100% magnet.
Don't forget that it has to keep the CD from sliding on the disc table. So a strong clamping force is the best here.
I don't believe the magnetic clamp will affect anything in the CD playback system. You would see this as a change in the eye pattern. If something will affect the sound in any way, it will be seen as error flags or in worse cases, degraded eye patterns.
-Chris
IMHO the masses of clamps and tables are not an issue at all.
Try slowing down the disk while playing by touching the surface with a finger, but use a good player with a good brushless motor and stable spindle, no worn out mabuchipuchi...
No sound detoriation occurs until you use too much force, then the servo can not compensate disk speed and music will have real dropouts or there will be no sound at all.
Just my imagination: only because of fifo buffer underflow, nothing else.
Disk speed changes continously while playing, no problem for the motor or servo even with a very heavy table, just might take some time slowing down speed when skipping to a higher track number.
Also it is real nonsense to save mass on a clamp: It has a low mass moment of inertia because it has a small diameter, while the CD even with its light weight but high angular mass because of large diameter has already a high mass moment of inertia and a good will change of clamp mass will be translated to a negotiable change of total mass moment of inertia...
Correct me if I am wrong.
I plan to built a transport with a heavy table and hanging laser...
Try slowing down the disk while playing by touching the surface with a finger, but use a good player with a good brushless motor and stable spindle, no worn out mabuchipuchi...
No sound detoriation occurs until you use too much force, then the servo can not compensate disk speed and music will have real dropouts or there will be no sound at all.
Just my imagination: only because of fifo buffer underflow, nothing else.
Disk speed changes continously while playing, no problem for the motor or servo even with a very heavy table, just might take some time slowing down speed when skipping to a higher track number.
Also it is real nonsense to save mass on a clamp: It has a low mass moment of inertia because it has a small diameter, while the CD even with its light weight but high angular mass because of large diameter has already a high mass moment of inertia and a good will change of clamp mass will be translated to a negotiable change of total mass moment of inertia...
Correct me if I am wrong.
I plan to built a transport with a heavy table and hanging laser...