OLD THREAD DAC End by Andrea Ciuffoli

[apelizzo]

Originally Posted by Yunick

Thanks for the reply.

I will also try Adamus LED-mod eventually, but now I just want to get to know the sound of this DAC also. The sound is very addictive.

It's indeed a great project with great "modding" potential

Yes, I agree the sound is very addictive and very refreshing. I really enjoy 6pm to 1am every day, never tired to listen and I switch off with regret. One of the mods I'm waiting is also the I/V stage power supply upgrade to Shunt Regulator, constant current heater supply and Adamus mod(but with TL431 instead of LEDs). Bye Bye caps.

[flocchini]

Originally Posted by apelizzo

Yes, I agree the sound is very addictive and very refreshing. I really enjoy 6pm to 1am every day, never tired to listen and I switch off with sacrifice. One of the mods I'm waiting is also the I/V stage power supply upgrade to Shunt Regulator, constant current heater supply and Adamus mod(but with TL431 instead of LEDs).

I for one would be very interested in your results.

[Ekkeri]

How big power handling capacity R5 10k in I/V PS should have? I have 1/4W resistor, but it's so small..

[erwincantona]

Originally Posted by flocchini

I did omit the filter and I left out R30-R33. I may do the experiment and put them in although I am quite happy with the sound.

I also started with the Adamus mod. I was intrigued by Adam's comments and follow-up discussion.

This is a great project. There are potential changes that could be made. Part of me just wants to listen to the music.

@flocchini

Can you show us how to do "ADAMUS MOD"
is it on Salas Board?
It would be very nice if u post with pic ( like lampizator did, with some arrows points some component you've modded)

[flocchini]

See post 986 by Adamus.

Enjoy

[fredlock]

Originally Posted by CustomHT

So how would I wire that up tho?

For the 2.5V/3A it goes blue wire, brown, blue
For the 3.15V/3A it goes glay, black, gray
for the 260v - 230v - 0v - 230v -260v is goes green, violet, orange, violet,green

Hi CustomHT,

I have the same transformer as yours, R80-36. I haven't connected yet since I'm still waiting for parts that I ordered.

This is how I will connect it

You have 2 center tap 3.15V/3A per winding, Gray, Black Gray

You have 1 center tap 2.5V/3A per winding, Blue, Brown, Blue

To make it 8.15V for the heater filament, you only need the 2 Blue wires, ignore the Brown wire just insulate the end of it. That gives you 5Vac/3A. Then connect one of the blue wires, to whichever 3.15V center tap you want to use, to Gray wire and the black wire will be 0V reference. Measure it with the voltmeter and if you don't get 8.15V, you might want to reverse the connection of black and Gray, as what housing had mention earlier. It might be out of phase. You were also asking if you can parallel the 3.15V winding. I think you can but this will become 6A which I don't recommend.

In regards to the 260Vac, I think you can parallel the winding to achieve the maximum current rating, tie up Green and Green wire and orange will be your 0V reference.

Let's consult with the veterans here. Guys, correct me if I'm wrong. I'm just trying to help CustomHT. I know he asked this question like 3 times already and nobody had given him a detailed answer of the transformer connection.

Thanks,
Fred

[housing]

Originally Posted by fredlock

Hi CustomHT,

To make it 8.15V for the heater filament, you only need the 2 Blue wires, ignore the Brown wire just insulate the end of it. That gives you 5Vac/3A. Then connect one of the blue wires, to whichever 3.15V center tap you want to use, to Gray wire and the black wire will be 0V reference. Measure it with the voltmeter and if you don't get 8.15V, you might want to reverse the connection of black and Gray, as what housing had mention earlier. It might be out of phase. You were also asking if you can parallel the 3.15V winding. I think you can but this will become 6A which I don't recommend.

Thanks,
Fred

I have no practical experience with this transformer, but I do think that's the correct way of getting the filament AC voltage.

Originally Posted by fredlock

In regards to the 260Vac, I think you can parallel the winding to achieve the maximum current rating, tie up Green and Green wire and orange will be your 0V reference.

Thanks,
Fred

I think you can't parallel the 260V AC like that.

Use 2 diodes as a full wave rectifier at each green wire instead of a bridge rectifier to get the rectified high DC voltage, orange will be your 0V reference.

[Nikon1975]

Do some of you have experience with the e-bay seller for the AD1865 recommended in the board instructions?

Did someone compare how that chips work compared to the Digikey one?

Thanks,

Davide

[ksnider1]

I want to share my work in progress, look at those sausages in I/V stage, lol

[Yunick]

Nice work Ksnider1!

Very neat and tidy.