Marantz CD63 & CD67 mods list

SimontY said:


Hmm, the schematic doesn't look *too* hard for a beginner to follow :rolleyes:


Valves are easy too work with. Just remember the voltage !!! :devilr:

On this circuit, the main thing is to use "good quality" components after the dac, matched as close as possible.


6h5c
I had something along these lines in mind for my balanced stage.
Self-balancing cascode with the output taken from cathode for low-z.
 

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SimontY said:
Very interesting Ray. Your amp looks well put together, a DIY job?

The only bad thing is I now feel maybe I need this "new level" before mine will be its best!

Hmm, the schematic doesn't look *too* hard for a beginner to follow :rolleyes:

Hi Simon,

Yep, I built the amp myself. There's some more pictures of it (and me) here. :D

The advantage of tubes is that you need very few (passive) components to make a good working circuit. A simple common kathode circuit is stable and has enough bandwidth by itself already, and the amplification is not too high, so you don't need feedback to "fix" all that. I think feedback is a killer for the sound. Furthermore the characteristics of a tube are more friendly compared to a transistor. The same philosophy can be followed with transistors or FETs though.

The high voltages require a different approach to building, but once you get the hang of it, it's very easy. It's more mechanical compared to a PCB with parts, most circuits can be hard-wired.

Regards,

Ray.
 
poynton said:
On this circuit, the main thing is to use "good quality" components after the dac, matched as close as possible.

I had something along these lines in mind for my balanced stage.
Self-balancing cascode with the output taken from cathode for low-z.

Hi Andy,

This is starting to look like the Tubes section....

Nice circuit, didn't know that one yet. Where did you find it, or did you design it yourself?
It has balanced inputs :D.
Technically you only have to buffer the output you are going to use with a kathode follower.
Will save you one triode :cool:. A bit like this one. I found it here.

Ray.
 

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I think I got the idea from Kennedy Audio (?) on the web years ago.

I also have seen the circuit you posted.

( I try to avoid the site you suggested unless I have some time to waste - it takes such a long time to update !!! )

Andy


PS I like your pictures - a study in concentration !!
 
SimontY said:
Hehe, nice haircut ;) Not how I imagined you'd look, lol
Your work looks extremely well done, I bet it sounds like it too.

rowemeister [/i][B] Just looked at your pics Ray.......are you sure you know what you are doing. :smash: Only joking mate. Very impressive;) [/B][/QUOTE] [QUOTE][i]Originally posted by poynton said:
PS I like your pictures - a study in concentration !!

Thanks guys. By the way, i'm not in the military ;)
Just have no curls :D

Ray.
 
poynton said:
The toroids hanging off the back are something I want to avoid !!!!!!!!!!

Uuuuugly! Indeed. I'm going to try and keep everything under the hood.

SimontY said:
Heh, and to think I decided *not* to post a comment about military precision...!

rowemeister said:
I was thinking the same. hehe

I can imagine, since my shirt is also the right tint of green :D:D

Ray.
 
rowemeister said:
Admit it Ray you have gone AWOL and you dont want your identity revealed. lmao

SSSShhhh, next thing you know they'll come looking again for me...

SimontY said:
So err, some kind of "military-spec" parts? You see "ex-military" stock on Ebay.
I guess if you're actually *in* the military you can just get stuff like 0.0001% resistors, right Ray? Ok, I promise I won't say anything else now :shutup:

Well, there is mil-spec wire in there actually LOL :D
It's very nice silvered copper wire with teflon insulation. But I didn't have to rip it out of a Leopard tank, they sell it at AE-Europe. :angel:

Ray.
 

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SimontY said:

Damping the insides should help the sound, but the feet really ought to be replaced with hard cones. It's my experience that this provides a more lifelike sound than soft feet (more solid and tuneful bass especially).

Il look into getting some new feet asap, but do you have any recommendations for spikes before i do? 3 or 4 spikes ?
The sound deadening will be done last, after i have done all the circuit modifications that i have planned for the player.

SimontY said:

These caps block DC from going to the amp, as such they are near the output sockets - C655, C657 (left channel) and C656, C658 (right channel). I wouldn't worry too much about the DC, but you should measure it - just stick multimeter probes into the socket and turn the player on. Tell us what you get and someone will comment. DC is almost certainly dealt with in your amp though, making the caps ENTIRELY superfluous. They ruin the sound, again it's the bass more than anything.

Il try and get these caps removed asap, but what cable do you recommend i use to bridge the gaps, and would my non-silver antex solder be satisfactory (i may try to get some old lead solder off ebay)

SimontY said:


Audiocom Superclock2 for £70 is good value, as it used a proven design, uses nice parts, and it's ready made for you. I think if you don't want to spend too many hours poring over schematics and learning to build circuits just buy their parts because they seem nice and will certainly do the job.

Ok, IME, a clock upgrade like this takes the player from 5/10 to 6/10, then a psu takes it to 7.5/10 (only relatively speaking!). It is absolutely necessary to feed it good power, and I say 'dedicated' because it's known that the voltage rails in the CD63 are fully cr@p - this would explain my listening results.
:D

Ok il probably go for the superclock 2, and audicom super-regs +5v, 12v, and -12v. Are these easier to fit into the player?
Also, how do i power the superclock2 by using the voltage rails in the CD63 itself :rolleyes:, but ideally how can i power it using another PSU, and what do i need. I really don't want to spend a lot, and am not confident in making one unless im given guidance!!!

Thanks again

as:D
 
6h5c said:


This is the first attempt to get Thorstens Delta-Sigma circuit working and see what it does.

I have a HV tube PSU that I use for the supply to the circuit and used a small PCB tranny for the heater voltage. In the end I want to mount the tubes horizontally and fit everything in the player..

Now you are talking. A tube mod to the CD63 that fits in the player! It might be something a lot of us are interested in.