Marantz CD63 & CD67 mods list

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Well... I wondered for a long time and now I know how Russ Andrews does things...
As Brent is doing it also, I guess it really works but I am only sure now because of Simon´s statements (who I consider one of the real voicing masters here).

As for those who do not have earth like Matthieu, can we place a cap just between live and neutral ? (How large ?)

IMO these caps serve the purpose to clean mains and I can not stress more the importance of clean mains... (Even shielded mains cables can be clearly heard in my system) I believe it is a good idea.


Ricardo (In search of the BIG BANG)
 
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Mains can surely kill

4n7 across Neutral - Earth and NO more.

Really big caps across L-N domestically are just a plain wasteful idea. 30uF means 2.5A of reactive current - you don't get billed for it, but it creates waste in the generation network from heat etc just like a 2.5A load would (thats 600VA...). It also does not necessarily help (acoustica.org.uk: shocking! - scroll down a bit past 'Don't try this at home'...)
I am reading it now.

Thank you all.

PS
Just kidding about the big bang..... My last mains experiment was really enlightening (and expensive... I am listening to cassette tapes as the CDP is waiting for surgery).
 
I must add- I am definitely not an electrician!

But yes, big mains caps do make me nervous: at 240v/50z 4n7 will pass enough current to give you a belt, and 0.47uF far more than enough to kill you. You can't hear sonic improvements when you are crispy! I'm sure it can be done safely, but it's a bad 'generic recommendation' to DIYers IYSWIM.

Oh, and dialectric absorption can bite you long after they are unplugged. If you use large X caps you must ensure there is a decent 'bleeder' resistor permanently fixed across them.

Incidentally I think one reason using these caps is such a mixed-bag sonically is because you have no control of the supply impedance. Adding an X1 makes it the local nexus for all noise currents between the conductors - why attract that closer to your hifi? And adding a cap between N and E can links noise from Neutral into something your system 0v is referenced to...

OTOH I do use an (0.22uF X1)cap added to the fridge, and that stopped occaisonal clicks and pops nicely :)
 
...at 240v/50z 4n7 will pass enough current to give you a belt, and 0.47uF far more than enough to kill you.

So is this a bad time to mention the audio website that advocates putting 1000uF across neutral and earth?

I agree sonically it's a mixed bag with mains filters but even though I don't understand the higher levels of reasoning I can't agree as to just why it's a mixed bag. Personally I think there are more factors than your local mains and system, I think a lot is down to how you design the filter. With the smaller caps across L & N there's not much or anything audible to be gained, but stick a 10uF lighting cap there and it can sound smoother and more open with deeper bass... odd. Risk sticking 10uF across N & E and it gets better again.

Then there are the more complex arrangements and filters using transorbs, gas arrestors and such, but for those more special carefully thought out designs I'd just recommend buying one of Brent's nice products to save killing yourself etc ;)

Simon
 
So is this a bad time to mention the audio website that advocates putting 1000uF across neutral and earth?
Tell me you are joking; that's insane.

The sole point of the Earth wire is as a protective conductor to deal with fault conditions. 1000uF effectively shorts it to N, completely defeating the safety aspect

Incidentally, 1000uF would pass c.80A of reactive current at 240v!
 
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In my CDP, C815 (after the main 5vreg) feeds only the uCon, display and lazer mech.

I know it is too soon.... this machine only sounds at it´s best after min 30min playing but I notice a reduction in the bass presence. The bass became more detailed and integrated. There is also more presence in the mids (power zone) so the stereo imagery is improved.

Can not comment on the highs... too soon.