alu is not a shield, no better than air. steel or mu metal.
Thanks Adamus for telling me that. So do you think a metal plate between PCBs and Trans would do the job?
P.S. I received the two Obbligatos today. Look great!!
Oh yes, for sure. I have to shield them very well. I think the transformers will be sealed in aluminium box.
I Has use many This transformer, but i ont like it, it is very noise and not enough W. I am afraid it will be rung up, Not goot for Filament of parallel 5687
The transformer for DAC is very exelent! It is the best for DAC!
Where can I buy Elna Silmic at good price?
Thanks for the parts list Apelizzo.
I bought them from ebay last year from a Spanish seller. Search on ebay at the moment there are a few from China and Hong Kong. Be careful, I don't know if they are genuine.
I Has use many This transformer, but i ont like it, it is very noise and not enough W. I am afraid it will be rung up, Not goot for Filament of parallel 5687
The transformer for DAC is very exelent! It is the best for DAC!
R80-36 primary (0-115) x 2 /SCN: scondary (260-230-0-230-260)(200mA), 2.5-0-2.5(3A), 3.15-0-3.15) X 2(3A)
This is an 80W transformer not the little 40W, I can connect the 2.5+2.5+3.15 = 8.15V series for 3Amps AC. Two E182CC heater is 1.28A DC. Do you think isn't enough?
I'm currently using an identical one in my line stage amp. 2x6SL7 2x6SN7 1x5Y3GT Heater in AC though (I love AC on heater).
If buzzing I will take them to vanish again. The leakage is similar to toroidal transformer, much less then EI.
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I bought them from ebay last year from a Spanish seller. Search on ebay at the moment there are a few from China and Hong Kong. Be careful, I don't know if they are genuine.
Thanks, I bought them a few years ago at a guitar store online but can't remember where now..
R80-36 primary (0-115) x 2 /SCN: scondary (260-230-0-230-260)(200mA), 2.5-0-2.5(3A), 3.15-0-3.15) X 2(3A)
This is a 80W transformer not the little 40W, I can connect the 2.5+2.5+3.15 = 8.15V series for 3Amps AC. Two E182CC heater is 1.28A DC. Do you think isn't enough?
i think you can try it. im not sure it is good
So! parallel filament 5687 at 6.3 = 900mA. 2 tube= 1.8A
Almost ready. Only a few parts to go.
Nice job on the boards and thanks for the parts list.
I did notice that you use C22 and C24 on the DAC board whereas Quanghoe does not appear to. Any arguments for/against the .1microF bypass at these locations.
Thanks
Bob
It is very nice!
but the tranformer near The Iv stage.
you can rotate 90 degrees transformers, power transformers and barriers between the motherboard and features a shield!
And you do not use L1, L2 so you do not use R30, R31, R32 , R34 .
R8, R9 (2.2 Ohm) in the HV supply is very hot, you can change by R 1 Ohm parallel
The Cap in put is good, i like it!
Do you mean if we do not want to use L1 and L2, we no need to use R30, R31, R32 and R34 resistors also?
Do you mean if we do not want to use L1 and L2, we no need to use R30, R31, R32 and R34 resistors also?
yes! no use filter, do not use R30 to R34!
yes! no use filter, do not use R30 to R34!
You like with filter or with no filter?
You like with filter or with no filter?
I dont like filter! The sound I like.
Andrea and me make it in the PCb for many choice!
All PCb the are one difficult about the Filament of 5687!
All make is easy!
**********************************************************
**********************************************************
Hi everyone,
DO NOT TRUST THE PCB SILK SCREEN
CHECK POLARITY OF ELECTROLYTIC CAPACITORS. HEATER CAPS INVERTED
FOLLOW THE TRACKS AND CHECK EVERYTHING.
**********************************************************
**********************************************************
**********************************************************
Hi everyone,
DO NOT TRUST THE PCB SILK SCREEN
CHECK POLARITY OF ELECTROLYTIC CAPACITORS. HEATER CAPS INVERTED
FOLLOW THE TRACKS AND CHECK EVERYTHING.
**********************************************************
**********************************************************
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Which particular ones? It looks correct to me? However i'm a noob
Edit: C11 . I got ya.
Yep, it's C11 for sure.
Notice on this pic, the trace is on the other side, to what is shown on the board.
http://www.audiodesignguide.com/DACend2/Picture-077.jpg
Edit: C11 . I got ya.
Yep, it's C11 for sure.
Notice on this pic, the trace is on the other side, to what is shown on the board.
http://www.audiodesignguide.com/DACend2/Picture-077.jpg
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**********************************************************
**********************************************************
Hi everyone,
DO NOT TRUST THE PCB SILK SCREEN
CHECK POLARITY OF ELECTROLYTIC CAPACITORS. HEATER CAPS INVERTED
FOLLOW THE TRACKS AND CHECK EVERYTHING.
**********************************************************
**********************************************************
Please high light the any silk screen error here, it will help to prevent unnecessary caps explosion during start-up. Thanks.
**********************************************************
**********************************************************
Hi everyone,
DO NOT TRUST THE PCB SILK SCREEN
CHECK POLARITY OF ELECTROLYTIC CAPACITORS. HEATER CAPS INVERTED
FOLLOW THE TRACKS AND CHECK EVERYTHING.
**********************************************************
**********************************************************
good catch. that would have made a nice mess. did you catch it before power on?
quanghao, in the pic shown how come r3 (in the IV Power supply) isnt populated?
good catch. that would have made a nice mess. did you catch it before power on?
quanghao, in the pic shown how come r3 (in the IV Power supply) isnt populated?
Unfortunately not, but during maiden I only power up for few seconds (with a light bulb in series on AC mains), then I check if anything gets hot. I found the cap already warm. It's still working but I will replace it.
I just received R3 yesterday. It was a back order. Now it's in place.
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