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Re: Soekris Dam Dac
Posted: Sat Jan 16, 2016 1:06 pm
by nige2000
rab wrote:Hi folks, just thought i would say hi, as i have just this week received my Soekris dam 1021-12 -- actually, i think I bought the very last one, because shortly after I placed my order, I tried to add a second one for a friend, but was told that they are out of stock and do not know when they will make any more!
I have been dipping into this thread from time to time, and have been greatly enjoying reading about the sonic benefits of the various mods you people have been implementing. I hope to replicate at least some of them here in Australia, so it seems that one day soon I will need to sit down and read the entire thread from the beginning.
Keep up the great work!
cheers,
richard
Welcome
the more the merrier
keep us updated on your progress and ideas :)
Re: Soekris Dam Dac
Posted: Sat Jan 16, 2016 1:26 pm
by nige2000
tony wrote:jkeny wrote:If I understand it correctly, Nige is tying all the battery grounds together - that effectively bypasses any isolation on the input.
To correctly implement isolation the ground on the "dirty" side needs to be isolated from the ground on the "clean" side
Have to get a written instructions with colour coded diagrams off you John for effective grounding.
When we all met recently you were talking about floating ground and would love to understand how to implement that into the audio pc and isolate the pc from other components if that is even possible.
might take more than coded diagrams :)
ok your pc is connected to wall socket through a transformer i wouldnt particularly worry bout that
your
monitor will be gnded to earth disconnect earth wire in the monitors 13 amp plug thats one potential ground loop/differential
both lampizator and jadis is probably gnded to earth check continuity between analog input/output/usb gnd and earth pin on 13 amp plug
try the monitor first
an intona and the monitor earth fix should resolve much of the issues but a motherboard without clk mods would just fix it
Re: Soekris Dam Dac
Posted: Sat Jan 16, 2016 1:57 pm
by tony
nige2000 wrote:might take more than coded diagrams:)
ok your pc is connected to wall socket through a transformer i wouldnt particularly worry bout that
your monitor will be gnded to earth disconnect earth wire in the monitors 13 amp plug thats one potential ground loop/differential
both lampizator and jadis is probably gnded to earth check continuity between analog input/output/usb gnd and earth pin on 13 amp plug
try the monitor firstan intona and the monitor earth fix should resolve much of the issues but a motherboard without clk mods would just fix it
Ah I struggle on with the crap mobo and try some of the suggestions at some point:)
Re: Soekris Dam Dac
Posted: Sat Jan 16, 2016 2:03 pm
by nige2000
Re: Soekris Dam Dac
Posted: Sat Jan 16, 2016 2:43 pm
by jkeny
nige2000 wrote:jkeny wrote:If I understand it correctly, Nige is tying all the battery grounds together - that effectively bypasses any isolation on the input.
To correctly implement isolation the ground on the "dirty" side needs to be isolated from the ground on the "clean" side
spent a while testing this couple days ago
which was basically using the isolators as intended having the i2s unit fully isolated keeping both gnd and +3.3v separated both sides
versus merging both 3.3v and gnd of both sides of the isolators at the battery terminals
initially found fully isolated a half hair better (this difference is sq is probably not worth chasing if your in any way normal) however in the past i found isolation of i2s lines not much use when everything's cleanly powered (clean both sides) so i started to look for flaws in my front end 3.3v cell/rail
i found that after adding an additional cell and changing some wiring i could no longer find any negative effect having both sides of the isolators merged at the batteries
it may not be absolutely accurate to say it bypasses any isolation on the input as nothing has changed in the isolator chips the only way to actually do that is to remove the isolators and bridge across them
the isolators are still doing what they do and the power supply to both sides are going though a heavy duty filtration system in the battery cells
question remains if the isolators are removed would it be better or worse?
im really not sure
im considering investigating it
Interesting results, Nige
But if you are using the same ground on each side of the isolators you are no longer isolating the signal - i.e. the signal is passing through the isolation barrier and being affected by the same current noise (through the ground) on the other side of this barrier - remember every signal returns current via it's ground return to complete its circuit, otherwise it's not a signal (no current flow) - it's this current return that is the stumbling block for most people.
I would, in fact say that the way you are operating the I2S isolators may well be adding noise - the isolators themselves add some inherent noise into the signal but usually this is outweighed by the benefits of isolating the "dirty" from "clean" side - in this case you are not getting the benefits just the added "noise" of the isolators
Re: Soekris Dam Dac
Posted: Sat Jan 16, 2016 2:46 pm
by jkeny
tony wrote:jkeny wrote:If I understand it correctly, Nige is tying all the battery grounds together - that effectively bypasses any isolation on the input.
To correctly implement isolation the ground on the "dirty" side needs to be isolated from the ground on the "clean" side
Have to get a written instructions with colour coded diagrams off you John for effective grounding.
When we all met recently you were talking about floating ground and would love to understand how to implement that into the audio pc and isolate the pc from other components if that is even possible.
As Nige said - it ain't easy to take an existing design & "correct" it's grounding for audio use. In the case of a PC this is just too complicated to attempt. The various PS approaches with individual battery supplies to various functions of the PC has had some benefits but there's a limit to how far this can be taken & comes a point where as the Irishman says when giving directions "I wouldn't start from here"
Re: Soekris Dam Dac
Posted: Sat Jan 16, 2016 2:50 pm
by jkeny
nige2000 wrote:tony wrote:jkeny wrote:If I understand it correctly, Nige is tying all the battery grounds together - that effectively bypasses any isolation on the input.
To correctly implement isolation the ground on the "dirty" side needs to be isolated from the ground on the "clean" side
Have to get a written instructions with colour coded diagrams off you John for effective grounding.
When we all met recently you were talking about floating ground and would love to understand how to implement that into the audio pc and isolate the pc from other components if that is even possible.
might take more than coded diagrams :)
ok your pc is connected to wall socket through a transformer i wouldnt particularly worry bout that
your
monitor will be gnded to earth disconnect earth wire in the monitors 13 amp plug thats one potential ground loop/differential
both lampizator and jadis is probably gnded to earth check continuity between analog input/output/usb gnd and earth pin on 13 amp plug
try the monitor first
an intona and the monitor earth fix should resolve much of the issues but a motherboard without clk mods would just fix it
Yes & I would add - make sure all your gnded devices are plugged into the same extension socket - this reduces the possibility of there being a voltage difference between grounds i.e if you have a PC plugged into a socket on one wall & your DAC plugged into a socket on another wall, these may well be on different electrical ring circuits - in other words there grounds will not join up until back at the distribution board & this can lead to voltage differences between the grounds.
Re: Soekris Dam Dac
Posted: Sat Jan 16, 2016 3:11 pm
by nige2000
jkeny wrote:nige2000 wrote:jkeny wrote:If I understand it correctly, Nige is tying all the battery grounds together - that effectively bypasses any isolation on the input.
To correctly implement isolation the ground on the "dirty" side needs to be isolated from the ground on the "clean" side
spent a while testing this couple days ago
which was basically using the isolators as intended having the i2s unit fully isolated keeping both gnd and +3.3v separated both sides
versus merging both 3.3v and gnd of both sides of the isolators at the battery terminals
initially found fully isolated a half hair better (this difference is sq is probably not worth chasing if your in any way normal) however in the past i found isolation of i2s lines not much use when everything's cleanly powered (clean both sides) so i started to look for flaws in my front end 3.3v cell/rail
i found that after adding an additional cell and changing some wiring i could no longer find any negative effect having both sides of the isolators merged at the batteries
it may not be absolutely accurate to say it bypasses any isolation on the input as nothing has changed in the isolator chips the only way to actually do that is to remove the isolators and bridge across them
the isolators are still doing what they do and the power supply to both sides are going though a heavy duty filtration system in the battery cells
question remains if the isolators are removed would it be better or worse?
im really not sure
im considering investigating it
Interesting results, Nige
But if you are using the same ground on each side of the isolators you are no longer isolating the signal
i suppose i shouldnt say there still isolating when using merged ps however they are not directly passing through the i2s signal
i.e. the signal is passing through the isolation barrier and being affected by the same current noise (through the ground) on the other side of this barrier - remember every signal returns current via it's ground return to complete its circuit, otherwise it's not a signal (no current flow) - it's this current return that is the stumbling block for most people.
im aware of that
but i dont think gnd is a magical place thats infinite meaning if i took a gnd noise measurement at an ic gnd pin on the board i would assume it to be a higher noise level at gnd than on the ps battery terminal (being the lowest noise point available?), aghh... doin a shit job of explaining myself
I would, in fact say that the way you are operating the I2S isolators may well be adding noise - the isolators themselves add some inherent noise into the signal but usually this is outweighed by the benefits of isolating the "dirty" from "clean" side - in this case you are not getting the benefits just the added "noise" of the isolators
wouldnt be at at all surprised if that was the case
Re: Soekris Dam Dac
Posted: Tue Feb 02, 2016 11:46 pm
by randytsuch
FYI, at the diyaudio thread, Soekris said he is coming out with new firmware soon.
He is adding DSD support.
He is taking suggestions for easy to implement firmware changes.
I offered one, not sure if anything will come of it.
Randy
Re: Soekris Dam Dac
Posted: Wed Feb 03, 2016 5:15 pm
by rickmcinnis
Those isolators will not be needed with the SDTrans and I will want to bypass them.
Nothing more than remove them and install a wire from in to out?
There could not be any reason to retain them, could there?