Knew it wouldn't take long!!!
couple of BG's on opamp rails, BG on DAC analogue and SEPC on DAC dig. Main Dig 5v rail's now got a big Nichicopy, the DAC clocks got a reg and an SEPC and the whole volume control, final opamp,muting and the feed to the balanced op is bypassed with silver wire direct from the valve stage to the output.
Spent quite a bit of time with several datasheets and started to R.E. the PSU's including the distribution so I can isolate. Like most players, nothing too complicated but it takes a little effort to work it all out especially when you don't have a diagram!!!
I've also prepared a couple of HA dual's and HA singles ready to fit onto SOIC pads when I've calmed down a bit or maybe tomorrow whichever is sooner!!!
Plenty to do thats for sure.....I'll start its own thread even tho I cant see it having the 63 or 1541 following
Basic super reg on the 24 mhz xtal with SEPC. Just removed the 470J and attached the reg direct to the xtal
C83 and C84 +/- op amp rails, now BG std
C96 Dac Analogue now BG std
C62 +5v digital noe 820uF Nichicon Solid polymer
C76 DAC digital bypassed with SEPC
Opamps ready for swap out to HA's
So this is what i tlooks like at the moment
Sounds bloody awesome btw
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Got the old chip out with only 2 damaged pads. Should be able to connect those point to point if I'm careful. Just waiting for a chip to arrive from Hong Kong now, couldn't find them any closer.
Regards
Pete
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So far I'm using OPA2132, but I have ordered a pair of LM4562. Waiting for it to arrive. DC blocking caps have also been removed (haven't checked DC though). The rest will have to wait.
Still, I'm dealing with a bass of about 15db lower than it should be! Doesn't that huge difference indicate a fault?
How do I check for a faulty mechanism control? Where is it located?
Still, I'm dealing with a bass of about 15db lower than it should be! Doesn't that huge difference indicate a fault?
How do I check for a faulty mechanism control? Where is it located?
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This may be stating the obvious, but have you got another source you can plug in in place of the CD63? Use the same interconnects and see if you have the same lack of bass with another source. Also, if the input impedance of the mixing desk is very badly matched to the output of the player, you can suffer similar issues. This is why DC blocking caps are often much higher value than required. Low value can cut off low freq if the input impedance of the amp is either high or low (cant remember which way round it is) Can you plug the player into another amplifier? You need to be 100% sure its the player before you go too mad!
Just thought I'd share that my CD63 is a better transport than the CD Pro2 in that aero! Probably not suprising given the amount of work done. It'll be interesting to see how the Pro compares after some PSU and clock work
Just thought I'd share that my CD63 is a better transport than the CD Pro2 in that aero! Probably not suprising given the amount of work done. It'll be interesting to see how the Pro compares after some PSU and clock work
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I must reiterate that I am only a beginner, but I wonder if we're on to something here. I removed my DC blocking caps recently too, but I connect my player to my amp which I know has Mundorf Silver/Oils on the input - therefore I know that no DC is fed back into the player. A powered input would be something like a microphone input, which would have a DC offset to power the mic. I don't know what effect that would have on the op-amps, but I bet it'd do something. I also wouldn't mind betting that the input to your mixing desk has some DC offset. Have you tried just plugging into the CD input of a normal hi-fi amp/pre-amp?
That is not a bad score! The pads are very thin and lift off quite easily, nice job
I hope the new chip gets you going again...
This is a lot of bass roll-off. This can't be solved by clocking the servo or inserting a few caps (sorry Matthieu...). If you're sure it's the player, it looks like you have a problem with the analog filter, anything changed there?
Like Ian suggests: try another source and/or try the player in another audio system. If you have an oscilloscope, measure the output signal at multiple frequencies.
Ray
Hey Stabby, this is probably stating the obvious again, but if you want to properly enjoy your mods, you probably want to be using a decent hi-fi amp. I loved the sound of my PM66KI in stock form, but in truth it was not very revealing and it took some major upgrades to get it to the point where I could clearly hear the benefit of my changes to the CD player. If you're plugging into a mixing desk with EQ settings and whatnot, I'd personally be inclined to try reinstating the blocking caps.
I'm going out on a limb here but I suspect that your mixing desk input might be passing DC into your analogue output.
Oh, hey, by the way - I did a couple of things tonight. I undid some mods that were a big mistake; bypassing Black Gates with WIMA film caps. I have had no luck with bypassing at all and I've resolved to stop trying. It's only ever made sound quality worse for me. I also grounded my output RCAs to the star point rather than the chassis, and that seemed to improve matters also.
Also, for curiosity's sake, I sampled a constant volume 20Hz-20KHz test sweep and analysed it with Audacity. The resulting spectrum plot was as flat as a pancake, so that adds some credibility to the method, but it completely invalidates the graph I did a few posts earlier because it shows that the shape of the graph reflects the EQ balance of the recording rather than the player, which was different for Stabby's plot than my two.
I'm going out on a limb here but I suspect that your mixing desk input might be passing DC into your analogue output.
Oh, hey, by the way - I did a couple of things tonight. I undid some mods that were a big mistake; bypassing Black Gates with WIMA film caps. I have had no luck with bypassing at all and I've resolved to stop trying. It's only ever made sound quality worse for me. I also grounded my output RCAs to the star point rather than the chassis, and that seemed to improve matters also.
Also, for curiosity's sake, I sampled a constant volume 20Hz-20KHz test sweep and analysed it with Audacity. The resulting spectrum plot was as flat as a pancake, so that adds some credibility to the method, but it completely invalidates the graph I did a few posts earlier because it shows that the shape of the graph reflects the EQ balance of the recording rather than the player, which was different for Stabby's plot than my two.
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OK, on re-reading, that's a big conclusion to jump to. I second Ray's suggestion to try plugging into a different system. Basically try plugging into a designated CD input of something if you can.
Sometimes I'm a bit like a woman and although I'm 100% positive that Ray would have suggested doing exactly the above without my assistance, I think I suggested it first in this instance Ben!!!
I have only been able to try to connect my CD player to the AUX input of an old Technics amp. This amp works fine with my record player, no lack of bass on my records. I then did the same as I do with my record player: I use the tape output and connect it to the inputs of my mixer. Bass is still the same, no improvement at all.
A few other notes: I've had this problem for a very long time. I removed the DC blocking caps last week, so that's not the issue. These are all the mods I done (everything that's replaced has been done so with the parts mentioned in Ray's pdf):
Removed headphone circuit
Power supply
- Replaced C801/802 and C811/812
- Replaced C813/814/815
- Replaced Q811
- None of the other existing mods in this section
Opamps (CD53 doesn't have HDAM):
- removed C659/660 (no replacement, no bypass)
- removed R655/R656 (no replacement, no bypass)
- Removed QN05...08 (no replacement, no bypass)
- Replaced opamps
- None of the other existing mods in this section
DAC:
- Removed CD04, CD07 and CD15/16 (no replacement, no bypass)
- Replaced C605/606 with 470pf
- Replaced R605/606 and R611/612 with 12k
- None of the other existing mods in this section
Bypassed DC blocking caps and R657/658
A few other notes: I've had this problem for a very long time. I removed the DC blocking caps last week, so that's not the issue. These are all the mods I done (everything that's replaced has been done so with the parts mentioned in Ray's pdf):
Removed headphone circuit
Power supply
- Replaced C801/802 and C811/812
- Replaced C813/814/815
- Replaced Q811
- None of the other existing mods in this section
Opamps (CD53 doesn't have HDAM):
- removed C659/660 (no replacement, no bypass)
- removed R655/R656 (no replacement, no bypass)
- Removed QN05...08 (no replacement, no bypass)
- Replaced opamps
- None of the other existing mods in this section
DAC:
- Removed CD04, CD07 and CD15/16 (no replacement, no bypass)
- Replaced C605/606 with 470pf
- Replaced R605/606 and R611/612 with 12k
- None of the other existing mods in this section
Bypassed DC blocking caps and R657/658