hmmm, x10 posts more
I've spent hundreds of hours listening on different mods ... i 've sold eight CD53/63/67 hard re-worked ... and done the same on Studer A730 and Tascam CDRW2000 . Worth the effort on these too
regrounding and twin DAC (on the way)
In you opinion, what are the mods that yield the most improvement? I am going through Ray's list of mods, but it's a bit intimidating. It's assumed that the reader really knows their way around electronics...I have recapped a few amplifiers and know basic electronic concepts, but I am by no means an expert. For example, replacing 78M12/79M12 with LM317/LM337 seems like a worthwhile mod but there is not enough detail for me to confidently do it.
Also, regarding the mod list (http://raylectronics.nl/pdfs/CD67mkII-OSE_mods.pdf), can I cherry-pick what replacements to do? Or is it all or nothing? Are the replacements interdependent?
This is a looong way of work and experiments, a never ending story ... like cooking
The is NO definitive answer : everything is INTERDEPENDANT , anything you modify has a consequence on general noisefloor, so some improvements seem huge in a "relative" silent system and some very subtle mods may be EVIDENT only if listening is made on a very SILENT amplifier (tubed or solid state) as 1st stage of amplification determines noisefloor of the whole subsequent chain .
PSU seems the very 1st condition : i actually tolerate 250microvolts of NOISE on +/-12v rails ...
Noise is not the algebric sum of values, it is the quadratic sum of RANDOM generating sources (even a connector ..) cra-zy
PS : you shall have a very hard mesurment lab on hand and lot of spices (not Spice simul) in the kitchen ...
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Your mind seems to change in hourly tempo
And yes, this is a CD-67 thread, hence my question about twin-dac implementation in that player...
The is NO definitive answer : everything is INTERDEPENDANT , anything you modify has a consequence on general noisefloor, so some improvements seem huge in a "relative" silent system and some very subtle mods may be EVIDENT only if listening is made on a very SILENT amplifier (tubed or solid state) as 1st stage of amplification determines noisefloor of the whole subsequent chain .
PSU seems the very 1st condition : i actually tolerate 250microvolts of NOISE on +/-12v rails ...
Noise is not the algebric sum of values, it is the quadratic sum of RANDOM generating sources (even a connector ..) cra-zy
PS : you shall have a very hard mesurment lab on hand and lot of spices (not Spice simul) in the kitchen ...
The extent of my "measurement lab" is my trusty multimeter...
Hi everyone !
I haven't introduced myself yet, it's true.
I have for several years a Marantz CD-63 MkII K.I. Signature and I made the basic modifications : mount Dip-8 supports to be able to modify the AOPs easily.
I tested many amps (made in china so ... fake, copy, reuse, reject, ... ? )
Currently it is two pairs of Burr Brown OPA627BP for the pre-amplification and a 627/637 mix for the headphones.
Yesterday I noticed that this part was heating abnormally strong. Not to the point of going up in smoke and flames but ... it was still very hot.
Is this normal? Could I have burned something out by removing the amps just by "pausing" CDs too often, without turning the unit off?
The sound is still so clean.
Just that digital "tac" between each track. Misunderstanding of a pause by this reader, I think it.
So, thank you all for all these thousand pages that I have been reading for several years now. I am finally registered here and I will be able to add some messages among all the others.
I haven't introduced myself yet, it's true.
I have for several years a Marantz CD-63 MkII K.I. Signature and I made the basic modifications : mount Dip-8 supports to be able to modify the AOPs easily.
I tested many amps (made in china so ... fake, copy, reuse, reject, ... ? )
Currently it is two pairs of Burr Brown OPA627BP for the pre-amplification and a 627/637 mix for the headphones.
Yesterday I noticed that this part was heating abnormally strong. Not to the point of going up in smoke and flames but ... it was still very hot.
Is this normal? Could I have burned something out by removing the amps just by "pausing" CDs too often, without turning the unit off?
The sound is still so clean.
Just that digital "tac" between each track. Misunderstanding of a pause by this reader, I think it.
So, thank you all for all these thousand pages that I have been reading for several years now. I am finally registered here and I will be able to add some messages among all the others.