A NOS 192/24 DAC with the PCM1794 (and WaveIO USB input)

whatever you do, keep the signal wiring twisted together, as it is, you have a very good aerial that is radiating and receiving noise from just about every square inch of the chassis. the loop area is huge.

I would probably leave it in the orientation you have, the RCA analogue outputs are then connected to long cables anyway, while the i2s has very poor noise rejection and in this case carries the master clock too from the waveoi
 
whatever you do, keep the signal wiring twisted together, as it is, you have a very good aerial that is radiating and receiving noise from just about every square inch of the chassis. the loop area is huge.

funnily enough i have left them untwisted on purpose. whilst i don't profess to be an expert (as far from it as you can get actually) as a 'follower' of nva philosophy i think i'll leave it as is. thanks for the advice anyway, and i have kept the mainboard orientation as is.
 
did you used a 5-50ohm resistor for RCA cable capacitance compensation ? (RC filter )

--how the PCM1794 pins connect to ground using resistors or direct connection im asking myself how is better because mine works without resistors and its recommended +-10ma
(the ones that are set low)
 
funnily enough i have left them untwisted on purpose. whilst i don't profess to be an expert (as far from it as you can get actually) as a 'follower' of nva philosophy i think i'll leave it as is. thanks for the advice anyway, and i have kept the mainboard orientation as is.

wow, thats the first time i've ever heard someone deliberately increasing the likelihood of RFI, EMI, lowering CMRR, raising distortion (well this one seems quite popular). its basic housekeeping stuff, not pedantic, but hey whatever makes you happy.
 
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..PCM1794 pins 1,3,8,16,19,24,27
so these are connected directly to ground, no resistor to limit to 10ma ?

not sure wat to say here? most pins are actually ground and the rest are inputs to set initial state of the dac chip. these do not need any resistor. Resistors only come in handy when used as Pull up or pull down and you want to switch the state. As itis now, it is perfectly ok...
 
i know just wanted it.is that possible ? its convenient because i have very good soundcard and optical is less hassle.and will have switches from windows panel just using remote.
-- i learned many things from yours,its just interesting,i have NO studies in electronics ,managed somehow to assemble a lot of things,and got them to work very well,even understood how polarization in a sat tuner works.so this NOS is very interesting because its NOS and how to h'ell to you overcome the problem of electron being created at the juncture where the i2s is decoded ,because it will maintain its properties up to your ears - please respond to that with high pull and led
 
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Sorry, your request for support is not in scope of this thread and too broadly to give a useful answer. if you ask my help and experience to help you on your project, may be you can just email me with your specifics and I can see if I can give you some advice. this thread if for my dac, so lets stick to that. thanks for your understanding...
 
and about your DAC NOS pcm1794 dddac waveIO .. -
I saw on your pcb that the current limit - limiting resistor for 1x ic pcm1794 is 10R how that can be? will it last long enough ? pcm1794 digital section consumes 45ma at 24/192khz divided from 3.3V equals 73.(3) ohms.can you explain PLeASE ! i just like music im not engineer .why not 5v ?
 
the whole section, digital and analog takes 55 mA, so power dissipation is .055 x .055 x 10 = 30mWatt. it is 1 watt resistor, so NO problem :) what do you mean with why not 5 volt?

One thing shouldn't be the current limited for pcm1794 ?
so 55ma for analog + 55 for digital but different supplies 3.3v VS 8v
DIGITAl=i got the message 45 + (2x5ma) for Fm0-pin11+ Fmt1-pin12

-i ment V=RI ,please be short and on theme because im learning from it as many others,and i cant be disrespectful for 1 not 1+x ,we dont solve here AC currents vs activity of solar flares
 
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I am afraid, you are mixing quit some things up... this goes beyond normal thread communication. your ideas of Ohms law has nothing to do with implementing the pcm1794. there is no need for nay current limiting. the resistors you see in the design are RC filters to filter power supply noise or to decouple the digital path. Not sure what to answer more? if any one has a better answer, pease jump in ! specially on solar flares I am not an expert.
 
One thing shouldn't be the current limited for pcm1794 ?
so 55ma for analog + 55 for digital but different supplies 3.3v VS 8v
DIGITAl=i got the message 45 + (2x5ma) for Fm0-pin11+ Fmt1-pin12

-i ment V=RI ,please be short and on theme because im learning from it as many others,and i cant be disrespectful for 1 not 1+x ,we dont solve here AC currents vs activity of solar flares

I am affraid you're in the wrong thread.....
Please give us a break!
Ed