OLD THREAD DAC End by Andrea Ciuffoli

[le´flu]

Hi Quang Hao,
you wrote that you´d use 6c45 as Valve.
But this is a mono-triode-Valve and the e182cc
has got double triodes.....what did you change in
circuit?
Also Andrea wrote that D3A could be used...well
this is a pentode.....how to implement this one?

Greetings Ulf

 

[feket663]

From where did you buy, in order to avoid him?
I bought from tube_buyer but did not recieve them yet to tell.

diyaudiokit... from ebay

 

[rtd]

Got board today, thanks for this quick GB.
One observation on DAC PCB: There is no GND groundplane
Maybe it is not needed with DAC such AD1865
Anyway it matches Andrea Ciuffoli DAC prototype

To go on.
May i haved looked at A. Ciuffoli schematic before !!!
I don't understand few things :

- Why CS8414 pin 24 (M1) is connected to CS8414/AGND and not DGND
- Why using specific regulator (TL431) for CS8414 pin 18 which is M2
as M0 to M4 is to select CS8414 mode.
- Usually LC schematic is used for digital PS for proper decoupling, here there is no L used, is there any specific reason ?

Is there any specific tweak behind schematic used ?

 

[quanghao]

Welcome you. I can not understand why PCB Left to fast so. The assembly components are simple!

 

[quanghao]

Hi Quang Hao,
you wrote that you´d use 6c45 as Valve.
But this is a mono-triode-Valve and the e182cc
has got double triodes.....what did you change in
circuit?
Also Andrea wrote that D3A could be used...well
this is a pentode.....how to implement this one?

Greetings Ulf

No! i dont change Cricuit of Andrea, I can by E182cc, D3a! I have 2 6c45, I used them!
You can see!

 

[apelizzo]

Where can I buy a real, working CS8414? I bought 4 pieces from chinese seller, 1 was ok, 3 don't work. Please recommend me a reliable seller, who ships worldwide!

Last year I bought 2 from ferdsaudio on ebay and both were faulty. I asked the replacement and again were faulty. Incredible.

I then bought one here:
CS8414 CS8414CS to DIP28 (PCB adapter- SOIC28) - eBay Other, Electronic Components, Electrical Test Equipment, Business Industrial. (end time 12-Feb-10 04:54:58 AEDST)

and it works!!

Remember to always ground your soldering iron when soldering these kind of chips.

 

[quanghao]

Got board today, thanks for this quick GB.
One observation on DAC PCB: There is no GND groundplane
Maybe it is not needed with DAC such AD1865
Anyway it matches Andrea Ciuffoli DAC prototype

Hi! can you show me plesa???

 

[quanghao]

To go on.
May i haved looked at A. Ciuffoli schematic before !!!
I don't understand few things :

- Why CS8414 pin 24 (M1) is connected to CS8414/AGND and not DGND
- Why using specific regulator (TL431) for CS8414 pin 18 which is M2
as M0 to M4 is to select CS8414 mode.
- Usually LC schematic is used for digital PS for proper decoupling, here there is no L used, is there any specific reason ?

Is there any specific tweak behind schematic used ?

Sorry! I do not answer this question! thank you!

 

[rtd]

Hi! can you show me plesa???

There is 3 small area behind the CS8414, the AD1865 and the 74Hcxx but not "wide enough" to form a large groundplane.

May be one complete layer could have been used to form the ground plane but may be difficult to route. But I haven't tried so i don't know if possible

 

[rtd]

Ok we can use LC configuration using 120uH inductance in place of 10R.

 

[toufu]

How critical are the Sanyo Os-Con caps? Can't we just use something decent like Panasonic FC's?

 

[quanghao]

There is 3 small area behind the CS8414, the AD1865 and the 74Hcxx but not "wide enough" to form a large groundplane.

It is on the top layer!

You can use L for R 10Ohm!
thank

 

[quanghao]

How critical are the Sanyo Os-Con caps? Can't we just use something decent like Panasonic FC's?

in the Board DAC-end you do not use other Cap, only Sanyo Os-con! you can ask Andrea!

In the Salas shunt you can use other Cap! with one If you like!

 

[Agi]

Is there a finalized parts list up yet (BOM)?

Or should we take the parts as shown here: DAC End 2 - the AD1865N-K with single ended vacuum output stage

Thanks

 

[quanghao]

This Board of DAC

 

[apelizzo]

How critical are the Sanyo Os-Con caps? Can't we just use something decent like Panasonic FC's?

You could, but I would say NO because Oscon is unique (special) cap and is the best for digital signal decoupling. On the analog though you could use something else like Elna Silmic for example.
Oscon SP is best for this purpose then SH.
Oscon SP around 220uF is easy to get from eBay while I cannot find the 47uF SP 16V

Anyone can help to find Oscon 47uF 16V SP series please? I can only find SA

 

[apelizzo]

Quanghao,
where did you find 47uF 16V Oscon? Are they SP series?

Farnell got them in stock at $8.00 each !!! Too expensive

 

[quanghao]

Quanghao,
where did you find 47uF 16V Oscon? Are they SP series?

Farnell got them in stock at $8.00 each !!! Too expensive

Yes! diffical fine 47uf 16v

 

[audiodesign]

The secondary for the filaments should be 8v 3A instead of 9v 1A.

and the 2 x 2.2ohm 3w resistor should be 2.2ohm 5w

 

[audiodesign]

Os-con 47uF 16v

SANYO OSCON SA Series 47uF 16V 16SA47M (lot of 15) su eBay.it Electronic Components, Electrical Test Equipment, Business Industrial