| spencer |
For those who want to hard wire the PMD100 in D1V3, here is the circuit diagram.
Those who has the converter board:
C1 and C2 are 0.1uF smd MLCC is on the bottom pads.
R1 and LED is on the top. PMD100 is U2 while U1 SM5842 is just a dummy pins.
Assembly sequency:
1. Solder C1, C2 and R1.
2. Solder the two 14 pins strip, align it using a 28 pins IC sockets.
3. Solder the PMD100 IC socket or PMD100 directly on the pcb top.
4. Solder the LED pin socket provided or LED direct on the pcb top.
Enjoy! |
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| spencer |
| D1V3 can also use 4 pcs cheaper DAC PCM1702UK on a converter board as shown. |
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| spencer |
Since PCM1702 output is only +/-1mA max, the IV resistor (R4, R13, R24, & R34) has to be changed to 3k (currently using 2.35k). I did not change the 2700pf silver mica value.
The other change must do is to remove the resistors (R148, R149, R150 & R151). Then the point A voltage will be able to adjust back to 9Vdc. In other words, Q41, Q43, Q45, & Q46 are not required.
The sound of PCM1704 is quite clean and clear a little bit less bass than PCM63. Overall the sound is good and very close to PCM63 sonic. With the cheaper cost of PCM1702U, it is a real bargin to use PCM1702U as replacement.
The next DAC chip can be tried will be PCM1704 or even AD1862 etc... For AD1862, the analogy +/-5V of PCM63 should be changed to +/- 12V. |
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| spencer |
Some photo of converter boards.
I have 8 pcs PCM1702U-K assembly DAC excess and would like to offer for US$15 each. Interested can PM me. |
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| spencer |
| Finally I find time to put the set into a casing as shown. Output changed to Black gage Non Polar 33uF 16V type. |
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| spencer |
Have made following changes so far and the sound improve a bit:
1. C4/C15/C25/C36: Use Black Gate Non Polar 10uF 50V E-cap.
2. C24/C35/C223/C229: Change from 1000uf 35V back to 2200uF 16V.
3. R123: 110ohm for XLR digital input; 75 ohm for BNC input; 50ohm for RCA input.
4. C10/C20/C31/C41: Change from Panasonic FC to FM grade; 47uF 25V to 100uF 25V. These capacitors are the analogy supply decoupling just next to the Jfet IV +ve supply. 6x11.2mm
5. C100/C124/C128/C140/C149/C173/C177/C189: Change from Panasonic FC to FM grade; 47uF 25V to 100uF 25V. These capacitors are the analogy supply decoupling capacitors just next to the PCM63 ICs. 6x11.2mm
6. Add a decouple capacitors Panasonic FC 27uF 35 voltage to all 5V regulators ground resistors at R97, R98, R105, R109, R112, R113, R126 & R127 (300 ohm). 5x11.2mm
7. Use PCM63P-K2, Y or KY chips.
Overall, the bass is much deeper and stronger. I try a PCM63KY chip and it really sound better, more harmonics and more musical. |
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| spencer |
Try some new capacitors and DAC.
1. C4/C15/C25/C36: Black Gate 33uf/16V N.
2. C10/C20/C31/C41: Black Gate FK 100uF 25V
3. C100/C124/C128/C140/C149/C173/C177/C189: Black NX 47u 6.3V.
4. DAC to PCM63P-K2 old parts.
Found the sound is more relax, a bit quieter, better separation of insturment, better sound stage and 3D. Very balance from high to low frequency. K2 is better in sound stage, more extend in high and low freq and better instrument position relative to normal PK version.
Cheers |
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| spencer |
Recently I upgrade my transport from Marantz dvd player to CD-PRO2 with China made controller. Now it is under testing but I find the sound of CD-PRO2 (from SPDIF out) with D1V3 is much better in sound stage, resolution and everything I can hear. The conclusion is that a good CD transport is really better than a normal grade CD transport.
Cheers. |
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| spencer |
Nothing new but just remain 10 pcbs/kits to clear off all stuff.
Last enhance with super big cap at the analogy supply as shown. Also change resistors R81 & R82 from 5R1 to about 1 ohm. |
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| spencer |
This is another option to use 8 pcs PCM1702U-K (two parallel for each DAC socket so that the output current will be 2mA and no IV resistor/cap need to be modified.
Use all pana FC cap on the analogy supply for decouple of the PCM1702 converter board.
Also you can see the analogy supply is using bigger Panasonic Audio caps. R81/R82 also change to zero ohm wire. |
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| housing |
Hi Spencer,
You've got mail! :D |
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