cs8414 & wm8740 dac (one dac chip)

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sparkle

sparkle

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Joined 2003
tnd-pipes.com/
schematic of the tube stage..... :D
 

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Kurt von Kubik

Kurt von Kubik

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Joined 2009
sparkle said:
Kurt - thnx for the reply :D

o.k. i can cut down the frequenca range (down to 20 or 30kHz) using LPF but i would not like to have one opamp more.. it is enough that i have one in I/V conversion inside the chip... :( :D
heheheh
o.k.... do You think LPF on the output of the dac (before the tube stage) should be o.k.???
Click to expand...
The DAC chip does not necessarely include an op-amp just bcause it is a U out DAC chip.
I think the WM8740 might feature a switched capacitor anti aliasing filter, which natviely makes it a U out chip. So you can find u out chips both with internal I/V conversion devices, and i.e CS4398 which is a u out chip without any I/V conversion.
 
B

borizm

Member
Joined 2010
WM8740 not need any LPF

Kurt von Kubik said:
You definately need to post filter the output from the WM8740.
It is a very noisy DAC, and on top of that, it performs better with post filtering. Wolfson Micro recommends a lowish 20 KHz LPF for the device, to meet their standards.
Click to expand...
Maybe, but I had to remove all the filtering capacitors from LPF at the output of WM8740 to get a proper sound.
OPA2132 works very very fine without LPF capacitors, creating unbalanced signal to discrete headphone amp which also hasn't got any LPF filter.
 
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