Marantz CD63 & CD67 mods list

[SimontY]

Originally posted by geoffgjones1
Time for a report.....
Large external transformer for the opamps (225VA) is a success. Loads of bass, clean mid. I am going to try an 80VA, just to compare. The 225VA is a little heavy!

I could barely tell the difference between 15va and 80va in my preamp (both toroids). I bet you hear very little difference also.

Simon

[Fidelity Audio]

Originally posted by geoffgjones1
Time for a report.....
Large external transformer for the opamps (225VA) is a success. Loads of bass, clean mid. I am going to try an 80VA, just to compare. The 225VA is a little heavy! This was to replace a small 6VA tranny. 12000uF Audio Elnas used, with ultra fast diodes, feeding schulz regs in the CD63KI.

Sound now compares well with my Linn LP12 for bass, probably even more detailed, although they do obviously sound "different". Now I will try a new PSU for the preamp in my PM17KI.

As for A class amps, I have always biassed my AB class stages more towards A class for the first few watts of output power with good effect, and much less heat! YOu have to be carefull though. I have to monitor temperatures carefully for the first few hours just in case i have taken things toooo far.

Cheers,

Geoff

Excellent , are those (12000uF) the blue caps used in the pm66KI amp?

I biased my well modded PM66KI more class A and i over did it the first time and the output popped while i was still adjusting it after a rebuild. I find adjusting it to the normal then tweaking up a little at a time works well (Well only if you monitor idle current from cold). Once its done the sound is much better.

I did have to upgrade my heatsinks with some custom ones as the standard 66KI sinks were not up to the job.

My 30VA inside the 63KI made a good improvement - even better than the 15VA I used before. Same gains you talk about. Worth the effort as it pushes the quality upwards

Brent

[geoffgjones1]

Hi Brent,

Yes they are the same! Nice caps. Swapped them out of my sisters PM66KI for a couple of 22,000 HQ pannies that I had lying around..... with little effect.

I did exactly the same thing with my sisters PM66, blew one channel. Managed to get a few transistor spares from marantz europe. More heatsinks added now!

I will be checking out the 80VA this weekend, and report back.

Cheers,

Geoff

[Fidelity Audio]

My (coke can) Silmics made a nice difference, more solid bass and smoother mids with no loss in the treble.

Here is a piccy of mine

It will be getting some 125W transistors soon as it is now 80W into 8 ohm and the PM66 transistors are rated at 100W max.

MY AMP

Brent

[SimontY]

Originally posted by rowemeister
Here is a piccy of mine

Rubbish, far too small.

[Fidelity Audio]

LOL

Well it just about manages to run my ATC speakers



Brent

[SimontY]

Yes, all 400mW of it.

[Fidelity Audio]

hehe

Noob

Brent

[geoffgjones1]

What value are those cans? I really do not think that my sister would really appreciate them to that extent, but maybe I need to try some in my PM17?

Anyway, I am going to replace my lazer soon, it must have aged at least a bit by now. Where could I get a unit from? Would I be better off getting a new complete drive?

cheers,

Geoff

[Fidelity Audio]

Originally posted by geoffgjones1
What value are those cans? I really do not think that my sister would really appreciate them to that extent, but maybe I need to try some in my PM17?

Anyway, I am going to replace my lazer soon, it must have aged at least a bit by now. Where could I get a unit from? Would I be better off getting a new complete drive?

cheers,

Geoff

The caps are 56V 22000uF. They were originally £200+ each. I managed to get them on the buyers section of this forum for £60 the pair not used. I think they are too big to fit in the PM17.

I would leave the laser if it is running ok, there are a lot of badly set up ones out there to buy, avoid Grandata for sure. I get all mine from CPC now, they come with the traverse and cost less than £20

Brent