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HQ-IV tube output balance DAC

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I'm getting 245V DC at C3 filter caps. Output is 153V DC!

Somewhere the circuit is dropping 90V but the heatsink isn't even warm and VR1 simply does nothing. I'll probe around the reg and get some readings

I'm hoping you can get yours to work. That's something to go on.

What is the rating of your transformer?

I will try to start building early. I work in the morning, I can only do this in the evening.
 
I'm getting 245V DC at C3 filter caps. Output is 153V DC!

Somewhere the circuit is dropping 90V but the heatsink isn't even warm and VR1 simply does nothing. I'll probe around the reg and get some readings

I'm hoping you can get yours to work. That's something to go on.

Passive420, I started my ps, installed the diodes, hv and lv, and its filter caps, connect the trafo, and I got 320v on the hv, and about 18v on the lv, no load though, but so far so good. I was able to finish the lv and everything works, was able to zero in at 12vdc (again no load), with the pot. Tomorrow, I will finish the hv. Hope you got yours to work.
 
Tube Output stage build

For anybody interested, I just finished my build and used quanghao's DAC-END R Dac. I used 12AU7 and 6DJ8 tube. This set-up sounds excellent, sound is very open, relaxed and detailed, fast but not hard or mechanical sounding, extremely musical.
 

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Dear quanghao,
Some of the members if not all of them have received the PCB and as I have seen some are finished, still I haven't received mine, and on the post office site there is no sign of them. Can you please verify what could have happed - it has been more then 2 months since you have sent it.
Thank you.
 
For anybody interested, I just finished my build and used quanghao's DAC-END R Dac. I used 12AU7 and 6DJ8 tube. This set-up sounds excellent, sound is very open, relaxed and detailed, fast but not hard or mechanical sounding, extremely musical.

hi!

you can use R iv for this IV, sound the better

1. Output 2V rms : R/IV = 18 R- Ohm
2. Output 3V rms: r/IV = 27R

thanks
 
Dear quanghao,
Some of the members if not all of them have received the PCB and as I have seen some are finished, still I haven't received mine, and on the post office site there is no sign of them. Can you please verify what could have happed - it has been more then 2 months since you have sent it.
Thank you.

please try one week, if you can not get.

so i will sent you other PCB.

thanks

but you need sent all full your information to me: address +your phone

quanghao
 
Question nr 2:Can i use 6N23 and Ecc99?
What voltage to use?

I'm planning to use 12AU7 and ECC99. Haven't decided on the voltage yet!

I'm also seeking advice on what transformer I can use. I ahve tried to source a customer made unit in Australia with a 184V secondary, but they're either really expensive (~$200) or the supplier isn't interested (e.g. Harbuch.)

Is there a generic unit I can use? If I have a 240V secondary, what's the range of usable B+ voltages I can use, e.g. can I go down to 220V B+?
 
I'm planning to use 12AU7 and ECC99. Haven't decided on the voltage yet!

I'm also seeking advice on what transformer I can use. I ahve tried to source a customer made unit in Australia with a 184V secondary, but they're either really expensive (~$200) or the supplier isn't interested (e.g. Harbuch.)

Is there a generic unit I can use? If I have a 240V secondary, what's the range of usable B+ voltages I can use, e.g. can I go down to 220V B+?

Yes . You can run at +b =220v. That is good .
No need use 260v .
+b can use from 220 v to 260v . Thanks
 
Status
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