Marantz CD63 & CD67 mods list

Got the machine working. Pretty happy so far!

Results still need to be interpreted, but a first listen gave:
+ clearer (even my girlfriend noticed, and that says a lot)
+ bass less boomy
- placement of voices and instruments became worse

LM337 = -11.9V (almost perfect)
LM317 = +12.7V

Would there be any effects from this?

I also measured the entry voltages going into the new regulators. According to the SM, should be +/- 20V.

Vin(LM337) = -17.8V (ok)
Vin(LM317) = 21.3V (ok)

Anyway, pretty proud of my first tweak (leave aside removing the muting stage)!
 
Muting and output caps removed, lm317 and lm337 in place. Still waiting for LM4562 to arrive...

But for now, I think you could describe it as more delicate.

Highs and mids are clearer, bass is less 'present'. Not sure how much I like it yet, it is not so warm anymore. I probably need to some to adjust to it as well ;-)

-Would there be any effect from the caps on the regulators to break-in over time?
-Is there an effect from the 'not exactly +/- 12V' output of the regs?
 
Its good to be the one now giving advice and not taking it! :eek:

Make sure you sort the decoupling caps C611-C614 when you do the opamps. As BG's are pretty hard to come by now, I'd go for Rubycon ZA at about 220uF there. While youre at it, i'd also replace the other 4 around the DAC (CD04,07,15 & 16) with the same value.

Bypassing the HDAM's is very straight forward. 1st you can remove the voltage supply to them (meaning the +/-12v supply will now only service the opamps) by removing 4 resistors inbetween the HDAMS (just in front of the 4 caps) R651-R654.

You should also remove and replace with wire links R613-R616 which are the supply rails to the opamps. The resistors were there to help stop interference from other circuits on the rail. As the HDAMs are now isolated (when you removed R651-R654) they will now hinder the performance of the uprated opamps.

The audio out from the opamps can be picked up by removing U210(L) and U212?(R). Pick up the audio from the holes closest the opamp.

If you are retaining the muting circuit, you can link direct to the place where you removed the output caps (as per pick). If you have already bypassed the muting, connect the wire direct to the phono's.

Another pic attached- Red=remove, Blue=Upgrade & Green=Wire link
*save the picture and view it with paint or similar, you can blow it up and see the detail better!

Ian
 

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Nice technical input as I was ready to go direct MKP to RCAs on the CD951... Metallic or carbon? Another part in the audio path ;)region from a saturated condition.

"CAPACITIVE LOAD DRIVE
The AD8510/AD8512/AD8513 are unconditionally stable at all
gains in inverting and noninverting configurations. Each device
is capable of driving a capacitive load of up to 1000 pF without
oscillation in unity gain using the worst-case configuration.
However, as with most amplifiers, driving larger capacitive
loads in a unity gain configuration may cause excessive
overshoot and ringing, or even oscillation.
A simple snubber network significantly reduces the amount of overshoot and
ringing. The advantage of this configuration is that the output
swing of the amplifier is not reduced, because RS is outside the
feedback loop."
The best way Ray?

If any of you wanna help that'll be lovely!
http://www.diyaudio.com/forums/digi...7-tda1547-vs-tda1541a-r1-vs-sm5872-story.html

Matthieu
 
If you reed a bit further in the datasheet (AD8510), some values for the snubber network are given. It depends on the capacitance of the interlink and input capacity of the next stage. But 500pF is a lot, I don't think any interlink has that much capacity. My Nordost has only 8.9pF/feet (which is quite low). A series resistor also reduces ringing, I never tried a snubber, maybe that works even better. I'd say try it, and see how it sounds :)

Ray
 
Member
Joined 2006
Paid Member
Hi Ray

I need to place a dos in a DENON DCD3300....

It is an old player built like a tank and surelly worth the work.

My first issue is related with some errors I am getting while trying to read discs... it does not read them all and most of the times, when reading, it produces a scratching noise (directly related with the CD spin speed).

Can you please tell me if I should replace the lens and if after that I could install the dos ?

Ricardo

PS: Sorry for the off topic
 
DENON DCD3300, PCM56 dac Ricardo. Very nice indeed!

I expect you'll need more gain from the dos, unless it has higher output than the TDA1541. You may also be better with a transistor version as opposed to fet as they're reputed to be better for current/voltage conversion, although I didn't try this.

Lee.

Lee.
 
Yes a DOS is probably not what you need. It's for balanced voltage output DACs.
This DAC has unbalanced current output and an internal I/V op-amp for unbalanced voltage output too.

The player may of course have two per channel for differential signals, I don't know.

If you use the internal I/V op-amps for v-out, and there are two per channel giving balanced voltage, you can use the DOS. (You could use it for unbalanced too but there wouldn't be much point.)

Maximum performance would be to use the current outputs and a discrete I/V stage.

But remember the DOS does not perform I/V conversion.
 
Lee,
I would be very happy if you can tell me how you spiced your TDA1547 ;)

Yes a DOS is probably not what you need. It's for balanced voltage output DACs.
This DAC has unbalanced current output and an internal I/V op-amp for unbalanced voltage output too.

The player may of course have two per channel for differential signals, I don't know.

If you use the internal I/V op-amps for v-out, and there are two per channel giving balanced voltage, you can use the DOS. (You could use it for unbalanced too but there wouldn't be much point.)

Maximum performance would be to use the current outputs and a discrete I/V stage.

But remember the DOS does not perform I/V conversion.

How do you know if it's balanced or not? I think it is as it looks symetrical...
Right now I plan on using an extrenal single opamps like top Analog Device or National Semi to do the work of the internal ones and the DOS it.

Again, I'm begging all you even if have different points of view (that makes us more rich!) on my http://www.diyaudio.com/forums/digi...7-tda1547-vs-tda1541a-r1-vs-sm5872-story.html ! Promise I won't do (too soon...) commercial break for my church again :D

Ricardo why not a new thread! That may be exciting =)
 

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