charas@ How did you bypass the HDAM ? Did you just connect a jumper wire between its in/output ? Have you isolate the power source to the HDAM and completely isolate the circuit ? If you have not done that the HDAM will affect the output impedance of your 4562 opamp thus the SQ.
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This "slowness" has been remarked on before when players are first modded, I noticed it myself as well. It's not that the cd is actually playing slower (you can check the play times of tracks to be sure) just the perception is that it is all a little slower. I'm sure there is some scientific explanation but I have no idea what it is. Maybe it's the way notes cut off.
Pete
Ben Hanke,i will desolder this evening the bypass ceramics and will report the results.
higlander,for HDAM i remove R651,652,653,654 R617/618 RH23/24 and insert a wire from U210/214 direct to the output RCA's with a 22R carbon resistor.
Is it correct?
I haven't insert any jumper wires on R619/620 because there are no resistors exist on my board...only silk screening.
Please be advised that mine is made in japan and it has the MKII board on it miners the jumpers for 10R resistors which discontinued on KIS and SE.
higlander,for HDAM i remove R651,652,653,654 R617/618 RH23/24 and insert a wire from U210/214 direct to the output RCA's with a 22R carbon resistor.
Is it correct?
I haven't insert any jumper wires on R619/620 because there are no resistors exist on my board...only silk screening.
Please be advised that mine is made in japan and it has the MKII board on it miners the jumpers for 10R resistors which discontinued on KIS and SE.
Easy, just short the Rs
or remove the Rs and replace them with hard wires.One more suggestion, hard wire the two fuses as the thin fuse wire restrict current flow, in particular, when your TX is having small VA. If you look at my previously uploaded photos you will understand what I meant.
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Hey guys, I finally treated my DOS to some 0.1% naked "Z"-Foil resistors last night in the filter locations where Brent used Welwyn. I've been running with generic metal films up until now. I haven't had a chance to listen yet.
Regarding the 'slowness', I've definitely heard some odd effects from modding in the past. It's probably very subjective how changes are perceived. I think it's actually a really good thing if you don't like what you hear sometimes. I'd be highly dubious about a straight journey of nothing but a series of stratospheric success. It can be demoralizing to backtrack, especially when the copper traces start to give up the ghost. HDAM bypass was a tough hurdle for me because it seems to need a fair amount of supporting PSU mods to sound better all round. Good luck!
Regarding the 'slowness', I've definitely heard some odd effects from modding in the past. It's probably very subjective how changes are perceived. I think it's actually a really good thing if you don't like what you hear sometimes. I'd be highly dubious about a straight journey of nothing but a series of stratospheric success. It can be demoralizing to backtrack, especially when the copper traces start to give up the ghost. HDAM bypass was a tough hurdle for me because it seems to need a fair amount of supporting PSU mods to sound better all round. Good luck!
If there is 'slowness' after a mod it might be caused by insufficient VA of the TX ( just guessing). My theory is when the opamps, the servo and other components draw current from the TX it causes a small voltage drop and that might affect the output thus resulting some "delays" (just a theory). I did not experience anything like this as I use BIG TXs in all my mods.
Re 'slowness': for me whenever I have done 'a/b' comparisons either on my own or along with others, the 'slower' sound invariably tends to be the 'better' sound. I can't technically explain why, other than to suggest that what I am hearing is a tighter, clearer version of events, with more space around instruments/voices and less overhang. Notes start and stop as opposed to merging together.
higlander,can you please tell me which post are the uploaded photos with the hard wired fuses?Easy, just short the Rs
One more suggestion, hard wire the two fuses as the thin fuse wire restrict current flow, in particular, when your TX is having small VA. If you look at my previously uploaded photos you will understand what I meant.
Now to the results of the mods so far.I have remove the bypass ceramics from the power supply and the sound become more cleaner.
As for the sound overall...some if not all veils been removed base notes go far lower with better control with tempo BUT i have the impression that the player is a bit more analytical and aggressive specially in upper mids and highs...and mind you my system is all based with tubes...so i rewarded with huge sounstage and incredible body in mids and highs....BUT it seems i can't find the solution with the 63 mods.My TDA1541 based players are more involving to the music events.
I am open to suggestions.
Great news about the bypass caps. Well, there's plenty to do. If you haven't already, I'd say put a big cap (e.g. 22,000uF Mundorf AG/Fidelity Audio SI) in the pre 5v reg position and upgrade your servo PSU to at least 50VA. It's also worth regulating your driver ICs, which is great bang for buck, if a bit fiddly.
See #19156 (http://www.diyaudio.com/forums/digi...ntz-cd63-cd67-mods-list-1916.html#post3435787) and enlarge the photo and you can see I have removed the two fuses. What you need to do is just hard wired them at the back of the PCB.
I know that you have carried out some mods to the clock circuit but that is NOT GOOD enough. I would suggest you should change the DAC clock with an independent low jitter clock, and consider changing the servo clock at a later stage. With a new clock in you will hear a BIG difference to the SQ.
From my experience, the most noticeable improvement is (i) bypassing the HDAM and change the opamps together with low noise voltage regulators (ii) change the 2 clocks and (iii) change the TXs with BIGGER VAs together with good quality BIG smoothing caps. Improvements can then be fine tuned by changing the other smoothing caps. and the filtering caps etc using Sanyo SEPC, Rubycon ZLG , Panasonic FC, mica or Black Gates.
After all these modifications your CD63 will be very smooth and have tube like sound but you need to fine tune them yourself to meet your own preference. Of the 8 mods I made for my friends they all have slightly different sonic signature to suit my friends' tastes.
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Couple of pics!
Z-Foils for DOS and new Jung/Didden Super Reg PCB:
Latest pic of my DOS with Z-Foils installed:
NICE Job Ben
Ben,
On looking at the pic of your DOS, it seems you have positioned the main pcb under the metal clip that protrudes horizontally from the back of the player. I believe that this clip is meant to support the pcb and hence the pcb should be positioned on top of it. (Others please correct me if I am wrong.)
Anyway, more importantly, how does it sound now?
On looking at the pic of your DOS, it seems you have positioned the main pcb under the metal clip that protrudes horizontally from the back of the player. I believe that this clip is meant to support the pcb and hence the pcb should be positioned on top of it. (Others please correct me if I am wrong.)
Anyway, more importantly, how does it sound now?
Yes, you have really good eye sight and I agree with you. The metal clip should be underneath the PCB as support.
Ben, do you thing you should use some silver wires from your DOS to the RCA sockets?
Well, the placebo effect of the Z-Foils is undoubtedly monstrous, so naturally I heard a giant leap in the perceived width of soundstage, placement of instruments, crispness of guitar strings and percussion, etc., all exactly as my highly suggestible brain expected. Even my little boy remarked that Juliana Hatfield's voice sounded 'clearer', so he's showing symptoms of being well on his way towards developing the same disease as his old man.
Can I really hear the benefit of 0.1% resistors in my DOS filter when the capacitors are 1% and the inductors 5%? Can I possibly hear the benefit of reduced thermal noise of just ten resistors in the context of a complete system containing hundreds of individual components? My common sense says 'no', but then he's clearly not calling the shots. He does have my ear on silver wire though... I mean, I have over half a metre of copper wire between the DOS and my pre-amp input. Will a few cm of silver wire before that change anything? I like the Kimber TCSS anyway - it gets REALLY hot when you solder it, so it makes a great connection, and the Teflon insulation doesn't melt easily.
Thanks for correcting me on that clip. I thought that was to keep the board from moving around.
Can I really hear the benefit of 0.1% resistors in my DOS filter when the capacitors are 1% and the inductors 5%? Can I possibly hear the benefit of reduced thermal noise of just ten resistors in the context of a complete system containing hundreds of individual components? My common sense says 'no', but then he's clearly not calling the shots. He does have my ear on silver wire though... I mean, I have over half a metre of copper wire between the DOS and my pre-amp input. Will a few cm of silver wire before that change anything? I like the Kimber TCSS anyway - it gets REALLY hot when you solder it, so it makes a great connection, and the Teflon insulation doesn't melt easily.
Thanks for correcting me on that clip. I thought that was to keep the board from moving around.