Valve DAC from Linear Audio volume 13

Hi Ray,


following:
- first option is BBB + Pavel´s BBB isolated reclocker redsign (only SMD components and only on top side)
- second option is COMBO 384 + Pavel´s DSD2.6 isolated reclocker (not yet designed)



Yes, header are SMD allowing carrier board male header to go through so Marcel´s frontend could be stacked


JP
 
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I still had to post the expected timing for the data and clock input section. Referring to the attached picture, this is what I calculated (with the SN74LVC2G86 connected, so without the clock division):

From A to B and Bi: 3.4 ns to 8.6 ns of delay, B in phase with A and Bi in antiphase
From A to D: data clocked in at the rising edge, delay between 1 ns and 9 ns
E and E': data transitions between 22.1 ns and 31.6 ns after the rising edge of Bi
C and C': rising clock edges between 1 ns and 4.1 ns after B and Bi, respectively, at minimum potmeter setting, between 10 ns and 17.3 ns after B and Bi, respectively, at maximum potmeter setting
 

Attachments

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R2 can be omitted when you connect the midpoint between R1 and R4 to ground (and the same holds with the Lundahl and the Chinese transformer).

Thanks. That's what I figured.

I'm hoping JP's reconstruction filter PCB design will become available to order some boards. If I go in that direction, the Silk TVCs will be easy to connect to the boards via their flying leads so no changes to the board layouts would be required.
 
Hello,


very busy last days but here the progress: reconstruction filter at outputs missing (and regulator tube with pico7 socket).



Carrier board allowing BBB and COMBO 384 variants: both dedicated reclocker redesigned.


Power supply on own board.


I´m on travel next week so no progress expected.



JP
 

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