OLD THREAD Hi-end phono preamplifier by Andrea Ciuffoli

[nikhilji]

Finally !

I don't post often here, but after much deliberation, I'm quite pleased with the completion of this D3A project !

I'm using the Broskie's Janus Regulator to power the phono stage for now. I began with Russian K75-10s bypassed with Teflon FT-1s. The bass sounded boomy. I had some AmpOhm Tinfoils PIOs for another project but I decided to try it out here. I'm must say, the caps sound good in this circuit. I finally upgraded one of the caps in the RIAA network to Russian Silver Micas.

I haven't had a chance to hook it to my turntable in my main system, but I've been testing using the iPhone thru the Hagerman's iRIAA. The phono stage sounds good across the frequency range, but I will only be able to do any sort of critical listening once I hook it to my vinyl rig.

B+ 193V with load

K75-10 PIOs in coupling stage

Playing Gotan Project from iPhone thru Hagerman's iRIAA

AmpOhm TinFoil PIOS

Russian Silver Mica in RIAA network

I have a Hammond box that I am going to enclose the Phono Stage and connect it to the Janus via an umbilical. I also have the Salas Regulator that I plan on building and tieing all this together in a single chassis but that will have to wait. For now, I'm a happy camper !

Last but not the least, much thanks to Andrea and Quanghao for their good work !

 

[tangmonster]

COOL , glad too see there are other people posting pictures. mine have been doing lots of duty ,and still going strong.

 

[quanghao]

[QUOTE=nikhilji;

You are doing great!
Congratulations!
Thanks

 

[boba1000]

Hello,
I tried to place a order on your web site today but was unable to complete the order . Web site said there were no shipping options to send the order to Glen Head ,NY USA. is this true or can I order the circuit boards. I also tried to order the PP amp boards.
Bob Adamo

 

[quanghao]

Hello,
I tried to place a order on your web site today but was unable to complete the order . Web site said there were no shipping options to send the order to Glen Head ,NY USA. is this true or can I order the circuit boards. I also tried to order the PP amp boards.
Bob Adamo

Hi! Have problem from my web??
quanghao.com
thanks your help!
Quanghao

 

[toufu]

Mine has been running great for a while now...

 

[pred]

Hello,

I am starting to build mine, bit by bit, it will take time but I hope to come around it at the end.

Small questions for PSU:
- Could following replacements IRF840 -> IRF830?
- How big should be 33Ohm resistor to have only 10-20mA just for testing of the shunt?
- Are leds red, green...?
- Where to find 56k 5w?

Thank you in advance,
Pred

 

[quanghao]

Hello,

I am starting to build mine, bit by bit, it will take time but I hope to come around it at the end.

Small questions for PSU:
- Could following replacements IRF840 -> IRF830?
- How big should be 33Ohm resistor to have only 10-20mA just for testing of the shunt?
- Are leds red, green...?
- Where to find 56k 5w?

Thank you in advance,
Pred

Hi ! Do you can see in circuit

 

[pred]

Thank you for more precision,

btw, I do not see zeners in this schematics? Also what about IRF840, I have some IRF830 so I was wondering. I see I can use 47k 5W since we are under 300V? This is quite different, then what we have in your older post...

Regards,
Pred

 

[pred]

Hello guys,

I must be blind. I started to populate the regulator board and do not see R12 bleeder resistor nowhere. Where is it?

Thanks,
Pred

 

[quanghao]

Hello guys,

I must be blind. I started to populate the regulator board and do not see R12 bleeder resistor nowhere. Where is it?

Thanks,
Pred

!it is near the cap 220uF!

 

[pred]

!it is near the cap 220uF!

Hello, I must admit I still do not see it. Can you circle it for me on the jpg of your layout please.

Regards,
Pred

 

[quanghao]

Hello, I must admit I still do not see it. Can you circle it for me on the jpg of your layout please.

Regards,
Pred

Yes it does have on board! but you weld it at the bottom capacitor 220uF 2 children, or no longer needed! it only to discharge the voltage!

 

[Josep]

pcbs

Hello,

Is still possible to buy the phono + PS pcb?

Thanks

 

[quanghao]

Hello,

Is still possible to buy the phono + PS pcb?

Thanks

yeS! i stil have some PCB
Thanks
Quanghao

 

[geek_83]

Hi
What do You think about using Russian SGM-4 Silver Mica CAPACITORS ??
ananiashvili2006 | eBay

 

[sugarn]

What is the Cag value of D3A tube in triode connect?

 

[frd__]

Hi
What do You think about using Russian SGM-4 Silver Mica CAPACITORS ??
ananiashvili2006 | eBay

I use them in this project - RIAA filter section. However, I have not run the board yet. Constant lack of time. I'll let you know how they are doing...

Cheers,
Frd

 

[Josep]

riaa changes

Is correct to change Rp to 1M and R1 to 280K in order to use C1=0.01uF and C2=0.0033uF (I have Auricaps 1% for these values)?



Thanks

Josep

 

[DerTrommler]

Hello,
is it still possible to buy a phono stage and and a shunt regulator. If i ngo on Quanghao it tells me no carrier to germany or switzerland?!!
Kind regards, Michael