Marantz CD63 & CD67 mods list

[Fidelity Audio]

Originally posted by AndrewT
Hi Rowe, I am surprised you came to this conclusion.
Source impedance is one of the main factors in screwing up the carefully selected filters built into most amplifiers.

Similarly, unbuffered volume controls also screw up the impedance matches needed for those input filters, but even worse than a high source resistance.

Can I suggest you try just the Lpad and tell us which suits your system/ears.

Already tried my friend

I am using a 475 ohm series resistor and a 100 ohm to gnd (both 0.1%).

To be honest I cant tell a difference and as both seem to work fine on my set up. Ive gone for the 'L' as it has one less resistor.

Brent

[SimontY]

Originally posted by awpagan
I need convincing.

transformers can be wound fairly tolorance.
specially made for specific tolarances to match certain impedances at very high prices.

change the input(source) or output(amp)
and the transformer is just a hunk of iron.

allan

Actually, I might never get to try this, as I'm going to be going a bit active soon and I don't think a TVC fits into these plans very neatly.

Allan, have you heard a TVC?

Originally posted by poynton


I haven't seen that, Simon.
Is it a new ad. ??

Andy

Hi Andy, it's old. They called it the Tenzing mod iirc, advertised on Ebay. It looked like it might sound very good, almost half as good as mine even

Simon

[Fidelity Audio]

A while back I mentioned I was in discussions with a bloke and we were designing a low noise voltage regulator.
Well I have a batch here to test out and can conclude they are sonically better than the audiocom super reg, this was heard by only swapping the main 5V reg in a standard CD63 with both regs.
To be honest they should be better as we designed them to be, using lower noise components.

The chip cap at the bottom of the reg (next to the voltage ref component) is 10uF.

Rowegulators LOL









I'll post the specs soon. Just a few details I need to check up on.

Brent

[poynton]

Originally posted by SimontY


They called it the Tenzing mod iirc, advertised on Ebay.

Hi

I've seen the Tenzing mods. I didn't think it used an output transformer.

Andy

[poynton]

Originally posted by rowemeister


Rowegulators LOL

I'll post the specs soon.

Hi

Very nice work !!
Will you be retailing them ??

Andy

[Fidelity Audio]

Originally posted by poynton


Hi

Very nice work !!
Will you be retailing them ??

Andy

They (to start with) are for doing our upgrade mods, but yes retailing them is a very big posibility. They are all RoHS too.

The pcb is designed to be a swap for the standard regs and also bolt to an heatsink. On a good heatsink the FET is capable of 8 amps.

I also have the negative version.

Brent

[6h5c]

Originally posted by SimontY
Hi Ray,

Do you like that limp, lifeless sound? I prefer the sound with a preamp. Gutsy, with bass. I lived a while with the CDP straight into the power amp and it was not good enough.

IMHO

Simon

Well, first of all, thank goodness I haven't got limp, lifeless sound! But no, I don't like it. My player goes through a selector switch and a stepped attenuator, then straight on to the power amp. So I have a few contacts and two resistors in the signalpath, and no limpness at all. If it's better with a preamp, which means more electronics in the pathway (so that's contradictive), there must be something wrong with the way the player matches with the amp. Because less stuff most of the times sounds better. Did you try a better/different interconnect? I noticed the previous one I had was rather thin in the low-end, so cables can make a lot of difference.

Ray

[6h5c]

Originally posted by avr300
Nice. Will you be making PCB's?

You got a typo. C5 + C6, listed as uH.

Originally posted by Glenn2
Nice work Ray!

Separate regs for each channel can't be bad either.

Thanks guys. C5 and C6 are supposed to be inductors, but I was too lazy to draw a shape, so I used electrolytics with the same outline .
And yes, i'm going to make some PCB's myself, but I don't know how much. If there's enough interest maybe a real batch can be made?

Ray

[Glenn2]

Hi chaps,

I put a common-mode choke in my CD67se (in the spot designed for it) but it seems to have sucked a bit of life from the sound.

I used the Panny part from Farnell (from Ray's list as I knew it would fit).

Do they burn in?

Am I hearing the effect of increased mains impedance?

[SimontY]

Originally posted by 6h5c
Well, first of all, thank goodness I haven't got limp, lifeless sound! But no, I don't like it.

Happy to hear it Ray! I didn't think for a moment you'd suffer much inadequacy in your sound

My experience gave me mixed feelings and I wouldn't say I'd never go back and try things at least once more before closing the door on such an idea. The sound I got wasn't gutsy enough, it didn't have the dynamic grip and vigour I was after. It was, however, very fluid and detailed, with very low grain. The quality getting better yet worse was very obvious in adding a preamp to the signal path. The next step is to reduce the impact of this as much as possible (low gain, good op-amp, good wiring, single stage etc.)

My interconnect was the Kimber Crystal Cu, an expensive wire.

My power amp was and is DIY using the National LM3886 non inverted with a gain of 34.