You seem to very focused so I believe sooner or latter you will have your CDP completely fullon 🙂
Focused? Obsessed is the better word. Having begun this, I want to see just where and how far it goes. Anyway I've invested too much to turn back now.😱
lol, yep.
Just a thought, but has anyone re-clocked the bitclock (bck) directly on these players?
Works wonders on TDA1541 players I've tried it on.
Lee.
No, I never tried it. I'm about to do it on a 1541 DAC though. It uses the clock from the Crystal receiver now. I'll use a Flea and a 4040 to create the needed frequencies. I'm very curious what the impact will be 🙂
Ray
Ray
It's always been very good when I've done it, especially if you're bypassing the digital filter.
Lee.
Lee.
I'm going to leave the 7220 in place for now, I don't want to take too many steps at once. I've read that the filter can bring good things, IF the supply-decoupling is o.k. So i'll have to experiment with that later. It's placed in a socket for now, so bypassing it is very simple.
It's not difficult to do some reclocking with the 63/67 DAC, I wonder if it would be equally beneficial with a delta-sigma DAC.
Ray
It's not difficult to do some reclocking with the 63/67 DAC, I wonder if it would be equally beneficial with a delta-sigma DAC.
Ray
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Hi Ray, definitely leave the 7220 in. I never liked the NOS sound personally. I just meant bypassing by not running the bck from the 7220.
It'll be interesting to try on a cd63/7, I reckon it'll be less of an improvement but should still be a good tweak.
Lee.
It'll be interesting to try on a cd63/7, I reckon it'll be less of an improvement but should still be a good tweak.
Lee.
Oh, of course... I have to look into that then, because the 1541 get's the bit and wordclock from the 7220 now. Probably a matter of cutting a trace or two...
Ray
Ray
Good thinking Lee.
I find clocking the decoder can cause problems where the laser does not always read. Why has no one thought of this before?
Brent
I find clocking the decoder can cause problems where the laser does not always read. Why has no one thought of this before?
Brent
Thanks😀
Good ideas are a rarity around here, but they do occur, lol.
It works well on the old TDA1541 chipset
Cheers, Lee.
I have by-passed the hdam circuits, upgraded the op-amps and fitted a low jitter clock. I was reading an earlier post regarding the dc blocking caps. Marantz use two electrolitics back to back. Firstly, can I replace these say with a wima 4.7uf non-polorised and secondly can I connect them directly to new rca,s, therefore bypassing the muting circuits? Is it neccessary to remove the supply for the muting? I'm not a techy so be gentle with me!
You can do as you said and it'll sound quite good! The Wimas are perhaps one of the less decent-sounding film caps but a film cap it is and so, SO much better than the electrolytics. Don't expect the warmest sound though with those mods.
Thanks for that Simon. The first time I by-passed the hdam circuit was when you did way back in January 2006 when the thread started. I think with the op-amp upgrade this is a very noticable mod. Iv'e modded several since then but iv'e never got round to the dc blocking caps. I'm a little scarred of lifting them completely. What caps and value would you suggest and do you think it worthwhile by-passing the muting circuit?
I'd always bypass the muting circuit because it's a free tweak and some people have heard a difference doing so. I've never noticed much of a noise issue after removing muting.
In a player running op-amps I'd be inclined to remove the DC blocking caps completely (or jumper them out/bypass with wire etc. It's a good idea to check the DC levels on the output (whilst on but not playing music, using a multimeter set to DC volts). If the voltage is in the tens of millivolts ie. about 0.05V or less I'd not worry about it. The thing is, almost all equipment down the line (amp or preamp) will have a capacitor or other measures to deal with incoming DC. If you have a DC-coupled amp and expensive speakers then obviously you don't want to do this as it could damage your speakers.
If you must have a cap in there then of ones I've personally heard I'd not hesitate to recommend Mundorf MKP, Clarity Cap SA or Mundorf Supreme in order of increasing price and sound quality. Go for 4.7uF.
Simon
In a player running op-amps I'd be inclined to remove the DC blocking caps completely (or jumper them out/bypass with wire etc. It's a good idea to check the DC levels on the output (whilst on but not playing music, using a multimeter set to DC volts). If the voltage is in the tens of millivolts ie. about 0.05V or less I'd not worry about it. The thing is, almost all equipment down the line (amp or preamp) will have a capacitor or other measures to deal with incoming DC. If you have a DC-coupled amp and expensive speakers then obviously you don't want to do this as it could damage your speakers.
If you must have a cap in there then of ones I've personally heard I'd not hesitate to recommend Mundorf MKP, Clarity Cap SA or Mundorf Supreme in order of increasing price and sound quality. Go for 4.7uF.
Simon
I change amps frequently and often repair older ones so I would not want to be without some sort of dc blockage. I will take your advice and try a Mundorf. I suppose if the amp has a cheap blocking cap fitted then a posh cap on the cd o/p isn't going to make an impression so I can see why they would be better ommited. Thanks for the advice.
Barry
Barry
I have another question which I don't think has been covered in this almighty thread. I know the cd63 uses the same vam1201/2 as the cd67 but can the whole unit be interchanged? The reason I ask is that I have noticed that the cd67 has an ic on the control board underneith the laser assy, whereas the cd63 uses transistors mounted on the side of the board. I would appreciate any help with this question.
I think the control board would need swapping over for this reason, were you to swap a transport from 63 to 67 or vice versa.