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Old 31st December 2012, 11:54 PM   #391
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I'm very interested in any PCB boards for the variations on the D3a and C3m and the new preamp and any masterfull powersupplies.
I can build it myself if I have a parts list and a well made PCB board or even just a list of parts (or buy parts markup 25 percent) and pictures (no insturections-unless really hard) of maybe 6 stages as you build so you can compare your progress to the original.
Please post me if boards are available!!!!!ASAP!
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Old 1st January 2013, 03:08 PM   #392
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Does anyone know if this is in the works or should I proceed with trying to build a D3a or the C3M amp point to point with a lot of the values missing? I'd much rather have
a pcb with easier instructions due to language barrier.
Thanks
Mark
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Old 24th January 2013, 11:33 PM   #393
rhing is offline rhing  United States
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Please advise how I should purchase the PHONO-ASH (Phono D3A) board and the SSHV power supply board to build this D3A phono stage amplifier.
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Old 27th January 2013, 05:50 AM   #394
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Quote:
Originally Posted by rhing View Post
Please advise how I should purchase the PHONO-ASH (Phono D3A) board and the SSHV power supply board to build this D3A phono stage amplifier.
Hi all!

many time i can not sell and produce it!
thanks

If you can open for me one GR in Diyaudio i will make it again!
Thank you very much!
quanghao
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update 06/14/2013 :http://www.audiodesignguide.com/DAC32/index2.html
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Old 30th January 2013, 01:18 AM   #395
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I have a mate [here in China] that has building custom Class A valve equipment [amps, pre-amps, etc] for >15 years.

He can do custom work[OTs, Chassis, PCBs, complete , and provide parts.

His last customer bought a 30W RMS Stereo Amp [Russian valves] with silver wire wound OTs!

Have photos on FLICKR and price list for Russian [and Chinese OEM] valves...........
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Old 1st January 2014, 11:25 PM   #396
pred is offline pred  Switzerland
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Hello quanghao and all,

I just realised that 3 years have passed since I purchased the boards. I have assembled the shunt but even if I have all parts project stayed in a drawer for so long...

Now I have some time on my hands and am keen to finish. I would like to mount the tubes on the top plate, and all components below. Since I will use the Front pane Express I was wondering if Quanghao can post a mechanical drawing of the phono PCB. I tried to do measurements myself but somehow am not sure for 1mm or 2mm here and there.

So can we get the drawing of
1. All dimensions from the center of 1 of the mounting holes (which ever does not matter)
2. The distance of all mounting holes.
3. The distance of all middle points for the 4 D3a tubes.

Thank you in advance,
Pred
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Old 1st January 2014, 11:37 PM   #397
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[QUOTE=pred;3760806]Hello quanghao and all,

ok, i will sent to you when i finis it for you!
thanks
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Old 25th January 2014, 06:16 PM   #398
pred is offline pred  Switzerland
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Hello when can I expect the drawings? I have done a large part and now want to do the metalwork.

Thank you in advance.
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Old 23rd September 2014, 08:36 AM   #399
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Default Next project ready with the D3a

Some months ago have found in my country the not-ready KIT by one guy. As in my stock are been many years ready a lot of stuff, like Altec Peerless 4722 step-up traformers, Cardas connectors, Jensen Capacitors and old USA resistors etc... i have decided to made this project ready for my Garrard 401. The results are very amazing and what is good--tubes are making more lively sound compared to transistor amplifiers. It also very good resolution in the sound. Best tube amplifier in this level! I am using end caps yet 0,22 uF. Think they are not enough. If I am comparing to high end transistor amplifier –there are more powerful sub- bass. It be very helpful, if somebody can tell , what upgrades are been as good step forward by this phono amplifier. Also what is small problem— slightly hearable hum in both channels. Maybe it is because I haven’t yet build shield . The transformers are separate for anode and filament voltage. There aren’t shield between primary and secondary windings. Maybe it is reason maybe not.

Please tell about your experiences with this amplifier.
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Old 23rd September 2014, 10:18 AM   #400
Jogi is offline Jogi  Germany
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Yes, the D3a is a very good tube, especially for phono. But because of the high amplification is is very sensitive for stray fields, and that is where the hum comes from in your build. You should think about building an external supply, and use shielded input wires.
Output cap should be minimum 1mF. RIAA caps and resistors should be matched as close as possible. And the Salas SSHV 2 is better than the first one you used.
But already in a simple version this is very good. BTW I found the attached circuit to be better, more linear and smaller resistor values in the RIAA for more dynamic sound. You can omit the Ecc288 Line output of course...

Have Fun!
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Last edited by Jogi; 23rd September 2014 at 10:20 AM.
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