Chinese PCB's for a DIY EAR 834p phono stage

[nostromo]

during the assembling

[nostromo]

some features:
- Electrolyte capacitors Nichicon KX - Fine Gold / Philips / BC capacitor
- MKP capacitors Mundorf Supreme S.G.O. (1uf) / Supreme EVO S.G. (0,10uf - 0,15uf) all with silvermica bypass
- diode MUR4100E ultra fast 4A 1000V
- Tube socket noval ceramic gold pin
- Valves JJ gold pin (selected trio)
- R-core power transformer mounted on silent blocks
- RCA Neutrik
- Manufacture of cable copper silver-plated semi-balanced configuration
- Supply cables 15awg copper silver plated
- Filtering supply with choke 20H 20mA Hammond 154E
- Potentiometer shots with Dale resistors
- All connections have been soldered, no screw connectors
- Cabinet use HiFi2000

time of realization 3 days (about 24 hours)

thank you all for your attention and GOOD MUSIC

[Rotsch]

hard work... great satisfaction

WTF !! 
Wow.....stunning.....

 

[nostromo]

thanks... 

[Chris65]

Excellent work Nostromo! (do you have a real name?) & glad you are satisfied.

You've used some very nice components. Interested in that R-Core transformer you have used. There are a lot on Ebay but didn't see any with those specifications. Can I ask where you found it?

If you can, try to find some nice NOS tubes, I think you'll find an improvement over the JJ's.

[niclaspa]

It looks very nice and I think that it sounds great too!  Great work! 

I agree with Chris on the strengths of NOS tubes over JJ tubes.  NOS 12AX7 can be a bit pricey, but I think that UOS (used old stock) is a great alternative!  Buy used tubes that tests good!  These small signal tubes have an expected life time of more than 10000 hours.  The chances are very good that you will buy a used tube that you can use for many, many years to come!  There are a few dishonest sellers on ebay.  So, if you don't have any means of testing the tubes, buy them from a trusted source.  This one, for example:

http://vacuumtubesinc.com/index.php/12ax7-12ax7a.html
http://vacuumtubesinc.com/index.php/12ax7-12ax7a-rca-4866.html
http://vacuumtubesinc.com/index.php/12ax7-telefunken-smooth.html

[nostromo]

Excellent work Nostromo! (do you have a real name?) & glad you are satisfied.

You've used some very nice components. Interested in that R-Core transformer you have used. There are a lot on Ebay but didn't see any with those specifications. Can I ask where you found it?

If you can, try to find some nice NOS tubes, I think you'll find an improvement over the JJ's.

Hello... my real name is Andrea and I live in italy

http://stores.ebay.it/FIND-HIFI/_i.html?_nkw=transformer&submit=Cerca&_sid=1117136446

I have bought from this seller ebay

if you send him a private message he realizes any transformer on your requirements in 2-3 days

[nostromo]

It looks very nice and I think that it sounds great too!  Great work! 

I agree with Chris on the strengths of NOS tubes over JJ tubes.  NOS 12AX7 can be a bit pricey, but I think that UOS (used old stock) is a great alternative!  Buy used tubes that tests good!  These small signal tubes have an expected life time of more than 10000 hours.  The chances are very good that you will buy a used tube that you can use for many, many years to come!  There are a few dishonest sellers on ebay.  So, if you don't have any means of testing the tubes, buy them from a trusted source.  This one, for example:

http://vacuumtubesinc.com/index.php/12ax7-12ax7a.html
http://vacuumtubesinc.com/index.php/12ax7-12ax7a-rca-4866.html
http://vacuumtubesinc.com/index.php/12ax7-telefunken-smooth.html

thanks

Hello
I mounted valves JJ I had already home to test the correct operation
is not a problem for me to buy after a while other 3 valves and replace jj

[nostromo]

and now is the time for turntable's upgrade... DC motor, new tonearm and hard damping!!! W.I.P.

[Chris65]

Ciao Andrea,

Thanks for the info. After I asked I did actually notice that some of these sellers offer different outputs on the transformers, so I have already ordered one for another project.

What part of Italy? I used to spend a bit of time there in my previous job.

[hatehifi]

Hi Andrea, just read this and  er, I mean, 

super fine work, sir. Would love to hear it.

 

Cheers!

[nostromo]

thanks...

[ZZMoko]

How much heat do these phono stages produce?

The reason I ask is I only have a small space below my deck to put a separate phono stage and I would be worried if it produced too much heat, although I could separate the power supply to another alcove with more more air supply around it if it's the power supply part that produces most of the heat.

Thanks for any information.

[Chris65]

The valves will produce more heat than the power supply in a tube amp. In this case, there will be heat from the valves but not excessive, say compared to a big power amp. Adequate ventilation shouldn't really cause any problems for components mounted above.

[ZZMoko]

Any chance someone could measure how hot the valves/top of the case gets?

I suppose as these are signal valves they should not generate too much heat, I can probably provide plenty of side ventilation to the case without any problem but it's venting from the top that would be difficult in such a tight area.