Marantz CD63 & CD67 mods list

Also, having extensively modded both the cd67 and cd63 I can agree with Brent in saying that the cd63 is the better sounding player when fully modded, it does however require two clocks to achieve this.

My cd63 has a clock on dac and a clock on decoder with the discrete output and some damn good regs, and I am very happy with the sound.

Can anyone comment on the gains of adding a dedicated psu to the rf and hf amps? This brought very large gains in my 67, and I'm just wondering if I can expect similar results in the 63.

Lee.
 
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rowemeister said:
How it sounding now Ricardo?
I am impressed Brent

Just installed the PSU, the DAC C1 clock, CD05 = 470uF OsCon and a LM340AT on CD04 (RD01 removed).

The +5v reg input is tapped on the big 10.000uF smoothing cap in the PSU.

During dinner I could hear much better timing, instrument placement, much more detailed bass lines.... :worship:

While it is settling, the sound is becoming better, just like a phono cart warming up, disc after disc, (my benz needs to play three records before it starts to sing).

Hummmm this is good, I am starting to compare the CD53 with the record player....

Next time I will do the servo clock.... hope it gets rid with the white noise type trebble..... I need more detail now.

Regards

Ricardo
 
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DAC C1 Clock

After some time, the sound is more integrated.

I have the same bass power but with much more control and definition.

The dynamics are really better.... It sounds as if I had replaced the power amp by a big Class A Denon.... I can play music louder without it becoming hard or restrained.

Really impressed.....:happy1:

This weekend I will place the other clock in the servo.

After that I am considering a discreet output stage.... Can you please point me to the right readings so I understand the differences between the opamp function and a passive filter with a discreet output ?

Regards

Ricardo
 
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6h5c said:

The HDAM circuit is nothing more than a discrete opamp circuit, connected as a buffer.
Hi Ray
Can you please explain what a buffer is ?
I understand the buffer in a computer is a memory region where you place data that can be used latter, but in audio, what is it used for ?
6h5c said:

However, it's better to get rid of the opamps entirely. They can be replaced by a HDAM circuit (like in the SA8400 or SA11) or a passive filter with discrete output stage.
The last solution interest me very much.

Can you please identify/explain the passive filter in your discrete output stage ?

Regards

Ricardo
 
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RCruz said:
Hi Ray
Can you please explain what a buffer is ?
I understand the buffer in a computer is a memory region where you place data that can be used latter, but in audio, what is it used for ?
Is this buffer used to adapt impedances between components ?


Another question:

The DAC outputs a PWM signal... than there is a filter to remove the transport high freq signal followed by an output amp...Right ?

So this arrangement looks similar to a class D amp...!!

Can anyone comment on this ?
I am having trouble understanding why this tech works so well in my CDP and does not in a final amplifier :headbash:

Regards

Ricardo
 
RCruz said:
Hi Ray
Can you please explain what a buffer is ?
I understand the buffer in a computer is a memory region where you place data that can be used latter, but in audio, what is it used for ?

The last solution interest me very much.

Can you please identify/explain the passive filter in your discrete output stage ?

Regards

Ricardo

Hi Ricardo,

A buffer (in this case a voltage buffer) is an opamp or discrete amplifier with the amplification factor set to 1. It has high input impedance and low output impedance and is used to buffer a signal source that has no low output impedance or cannot deliver much output current.

The passive filter in the output stage are the passive components (R1, L1, C1 and so on) just before the differential input. They form a 3rd order low-pass filter without active components, like a loudspeaker cross-over. Originally, an active filter is used in the player, with the filter components in the feedback loop of the opamp. This could indeed be compared with a class-D amp circuit. Only the player uses not PWM but PDM = pulse density modulation.

Regards,

Ray
 
Oh, thanks! I guess it's my second language then :cool:. I try to write as neat as possible, and I use Interglot sometimes to look up the right translation of dutch words. Especially when i'm translating pieces of text for my website.
That way you learn a lot too :D.

In the past, I did some translating of dutch product documentation at my previous job, that helped a lot too!

Ray
 
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6h5c said:


Hi Ricardo,

A buffer (in this case a voltage buffer) is an opamp or discrete amplifier with the amplification factor set to 1. It has high input impedance and low output impedance and is used to buffer a signal source that has no low output impedance or cannot deliver much output current.

The passive filter in the output stage are the passive components (R1, L1, C1 and so on) just before the differential input. They form a 3rd order low-pass filter without active components, like a loudspeaker cross-over. Originally, an active filter is used in the player, with the filter components in the feedback loop of the opamp. This could indeed be compared with a class-D amp circuit. Only the player uses not PWM but PDM = pulse density modulation.

Thank you Ray

You made it perfectly clear to me.

Should I consider Mauro´s mod on your discrete output stage ?

Regards

Ricardo