Analog filter for NOS DAC

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I've built a non-oversampling TDA1541A DAC with Pedja's PCB for year. After several tweaking and modification, I replaced the AD844 I/V output stage with resistor I/V conversion and 6922 SRPP output stage.
And then, I found the main schematic of Audio Note DAC 1.1 Kit from the site http://audionotekits.espyderweb.net/
Although the other NOS DAC manufacture 47Labs declare they don't place any analog filter in their DAC, AN use a slight filter (a 12mH inductor and a 10nF cap) after the output of AD1865.
Because it is hard to get good inductors (Solen's are good, but they're huge and expensive for 12mH), I just clone the AN's analog filter with a samll and cheapo ferrite style inductor. However, the result is positive - the sound now is relaxed and sweeter, and more musical than without filters.
I've read so much discussions about varieties of I/V conversion of NOS DAC, but the discussions about analog filters are rare. What do you think of the analog filter for NOS DAC?
 
zanden uses analog filters.

board.jpg


6moons review of the 5000mk2 dac.
 
Zanden's theory is wrong!

you will find the the correct theory
http://pdfserv.maxim-ic.com/en/an/A4903.pdf


this is my experience:
http://www.diyaudio.com/forums/showthread.php?s=&postid=672387&highlight=#post672387

this is the respone of NOS DAC in normal.......
An externally hosted image should be here but it was not working when we last tested it.


this is my calculation in the respone of NOS DAC.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.

An externally hosted image should be here but it was not working when we last tested it.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.