Happy new year everyone! Those fleas look good Ben, nice work, looking forward to hear your results soundwise. It's nice to follow this fine thread, thanks to all contributors.
Cheers to that. This thread is my favourite place on the web ever.
Thanks for the tip, Ian. I thought PK would be a fair swap for the ZLG but I'll consider swapping them for something more suitable.
I had fun building that PSU, and the big snap-in Mundorf caps are 40% off atm, and I was thinking: I have all these separate +5v 317 supplies powering my chips - should I build separate PSUs for those? (I've got the bug quite badly now)
If so, should I regulate them separately to, say, 8v, and how much VA is enough per individual supply? Thanks guys.
Thanks for the tip, Ian. I thought PK would be a fair swap for the ZLG but I'll consider swapping them for something more suitable.
I had fun building that PSU, and the big snap-in Mundorf caps are 40% off atm, and I was thinking: I have all these separate +5v 317 supplies powering my chips - should I build separate PSUs for those? (I've got the bug quite badly now)
If so, should I regulate them separately to, say, 8v, and how much VA is enough per individual supply? Thanks guys.
Ah, looking back, Ray said 7VA was enough for the DAC and Lee suggested 50VA for the drivers would be a more valuable next step than the DOS.
Mmm.. I have 3 quite compact quad 5v reg modules for the chip supplies (12 regs total, of which I'm currently using 10). I'm thinking I might get 3x 9v 7VA transformers and 22,000uF AG caps to feed them. I should have room down the right side for all that.
Mmm.. I have 3 quite compact quad 5v reg modules for the chip supplies (12 regs total, of which I'm currently using 10). I'm thinking I might get 3x 9v 7VA transformers and 22,000uF AG caps to feed them. I should have room down the right side for all that.
Hi Ben,
I think that whichever step you take, it will be an improvement! But if you haven't upgraded anything around to opamp section yet (like the filter components), i'd go for the DOS, it will make a big difference.
Ray
I think that whichever step you take, it will be an improvement! But if you haven't upgraded anything around to opamp section yet (like the filter components), i'd go for the DOS, it will make a big difference.
Ray
I've done some work there. My op-amp section is recapped with BG FK/N/NX and 1% silver micas, but resistors are original and buried under big caps due to bad planning. If 7VA is big enough for each chip then maybe I'll get the ball rolling on that while I wait for the XOs.
DOS parts will take some research, I think...
DOS parts will take some research, I think...
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Ben,
If you've done the op-amps and filter caps around them then I would suggest beefing up the servo supplies next. The DOS will only make a nice medium difference, the servo a LARGE difference.
Simon
If you've done the op-amps and filter caps around them then I would suggest beefing up the servo supplies next. The DOS will only make a nice medium difference, the servo a LARGE difference.
Simon
Ah, OK... I'll take a look at the 'Doing it Properly' stage of Brent's upgrade guide for the servo section.
Happy new yr to all,
been busy with work .All sorted a nice work space for modding, counter, scope lets ,see whats available.
alan
been busy with work .All sorted a nice work space for modding, counter, scope lets ,see whats available.
alan
Hi Guys, is the servo power supply mod is exactly the same as for the 67 and 63 cdp?. I am fitting extra torroid for the op-amp(67cdp) and thinking of doing the servo as well. Would it be a good idea for them to share the power supply ? or best leave the stock tranny to power servo as concern re noise interference?
Quan
The servo driver ic section is different in the 67. That's what the additional 5v reg is about on the heatsink in the middle of the board. You could use an additional tx for this supply for sure. I'd go for about 50va with a 22000uf smoother there 😉
Do any of you guys think coax from my clock to dac/servo will help only using silver wire @ the mo.
alan
alan
Dependant on length, I doubt it will make much difference. I normally use miniature coax grounded at the clock end only but as I say, I doubt you would ever be able to tell the difference!! ;-)
I've no idea whatsoever, but maybe well-screened silver coax would be best. It certainly sounds like it would be good...
I've done some mod (all from the good advice from this forum) on my Marantz 63 output stage after the op-amps & also by-passing the HDAM. I also removed the two 220uf capacitors before reaching the RCA output connectors. My player already sound fantastic. However will there be further improvements if the two100 ohms resistors & muting transistors are removed?
I recently bought a used Cambridge Audio AZUR 640C V1 and found there are also capacitors & a resistor immediately after the output of the op-amp pin 7. I thought of improving it as well like the Marantz CD63, can it be done??
Thanks & a Happy New Year 2012 to All!!!!
I recently bought a used Cambridge Audio AZUR 640C V1 and found there are also capacitors & a resistor immediately after the output of the op-amp pin 7. I thought of improving it as well like the Marantz CD63, can it be done??
- Can I actually remove the capacitors & resistor? Can I then connect the op-amp pin 7 direct to the RCA output? Any damages??
- What’s the purpose of the switch over contact (to ground), also connected to the RCA connector?
Thanks & a Happy New Year 2012 to All!!!!
You need to measure for any DC on the output before the caps (as you say on pin 7).
Assuming there is no DC or at least no more than a couple of millivolts, they can be removed safely. If there is DC present, you should replace with a 4.7uF MKP or better (Ampohm, Mundorf etc). The problem with most of these caps is they are fairly large by comparison. Generally speaking any electrolytic cap in the signal path is bad for audio (this includes xovers too!!!)
When you say switch to gnd, is that on the centre of the RCA? If so, that will be for muting.
There are a few threads for that DAC on the forum but the core principles are the same for everything!
Assuming there is no DC or at least no more than a couple of millivolts, they can be removed safely. If there is DC present, you should replace with a 4.7uF MKP or better (Ampohm, Mundorf etc). The problem with most of these caps is they are fairly large by comparison. Generally speaking any electrolytic cap in the signal path is bad for audio (this includes xovers too!!!)
When you say switch to gnd, is that on the centre of the RCA? If so, that will be for muting.
There are a few threads for that DAC on the forum but the core principles are the same for everything!
Great advice, will surely do some measurements for DC.
Yes the switch over to gnd is wired on the center of the RCA. So, it's for muting!
Thanks once again for the info. Will update this forum on how my Azur 640C sounds after mod!
Yes the switch over to gnd is wired on the center of the RCA. So, it's for muting!
Thanks once again for the info. Will update this forum on how my Azur 640C sounds after mod!
Hi guys, just a question re disc readability of the marantz. My modded 67cdp played with copy CDR of katie Noonan with ease but can not play the original disc. It gives an almost whirling static noise when playing original disc. Is there any reason for this? Laser mech?
Quan.
Quan.