Is it the same about low level spikes if the interface is run from a battery laptop? Because USB is at earth on PCs.
Nashbap had some finding recently about his protective earth connection and low level spikes.
Yes, I run laptop on battery when I use Arta. It is definitely more noisier result when my laptop PSU is connected.
I remember Nash’s post, but it seems a compromise which will allow to the whole circuit to float. To clarify, he left PEM Earth connected to chassis, but disconnected signal GND from Earth. Right?
I think I tried that too. I’ll repeat such test and let you guys know.
If anyway all my attempts will be not successful, I assume I can live fine with 100dB Dynamic Range.
If perfectionism will take over, then how about good quality input isolation transformers?
The one like this?
Jensen Transformers CI-1RR Audio Hum/Noise/Buzz Eliminator/ Ground Isolator | eBay
P.S. My precious post is all messed up with attachments. Sorry about that. Tapatalk mess....
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Not sure of his details, he could clarify further. You can float signal GND with yin yang diodes or PE with a heavier bridge and still be safe in case of earth current path is needed on a hard fault if that's a remedy for best harmonic noise floor in a build.
On the other hand you are right, -120dB buzz spikes aren't the first thing you can pick up in the dark, but its a nice thing debugging stuff when you have the tools to spot them.
Then again maybe its not about a loop, there are several big components interconnected in there and it can simply be as much interference they gather form the nearby trafos field and mains cabling. A pot ups the impedance and they ride on. Are there differences with lid on lid off? That could give a clue if its about a field.
On the other hand you are right, -120dB buzz spikes aren't the first thing you can pick up in the dark, but its a nice thing debugging stuff when you have the tools to spot them.
Then again maybe its not about a loop, there are several big components interconnected in there and it can simply be as much interference they gather form the nearby trafos field and mains cabling. A pot ups the impedance and they ride on. Are there differences with lid on lid off? That could give a clue if its about a field.
Salas & Co. 
Before i forget and getting into xmas kindoff-mode
let me say that my DCG Pre. is more than 3 years old and still singing.
I didn't check bias etc.. last year or so, but dc on the output's still ~0
It's almost used every day, so having a lot of hours on it now.
Jesper... Thanks guy's
Before i forget and getting into xmas kindoff-mode
let me say that my DCG Pre. is more than 3 years old and still singing.I didn't check bias etc.. last year or so, but dc on the output's still ~0
It's almost used every day, so having a lot of hours on it now.
Jesper... Thanks guy's
No obvious difference when lid is closed vs. it is opened. Not the same noticeable change as I saw on my fist unit. I"ll go for permalloy and try to make a wall to isolate tranys. Will update forum accordingly.
Salas I let the preamp burn in on the bench for 90 minutes watching the offset and adjusting when necessary. terminal heat on heatsink was 88 F. 25 degrees over room temp. I then turned it off wired the vc and rca's back up put the chip in and put it in my system. You should call this preamp W.O.W !!! WINDOW ON the WORLD. not only does it have an immense soundstage it will actually transport you back to the acoustic event! Dynamics are fabulous, instruments come out of a blackness that scare the crap out of me. Bass is there when it is there and it is powerful, listen to Jennifer Warnes- the hunter. this cd has so much bass it overwhelms most systems. try "way down deep" for instance. this preamp has an immense soundstage, powerful dynamics, and a sweet disposition . Thank you Salas and Tea Bag--Mark
Congrats!nice built!what is the rest of your system?i think that dcg3 deserves a better pot!
Yes you can piggyback for 2x. Your plan is build guide's note 4 compatible.
What is your now Alps Blue nominal value? Fellow builder killie99 mentioned replacing his Alps Blue with TKD 2CP-2511 very favorably in post #4047 but he did not mention its value. Maybe he could enlighten us if he reads. There is a 20K model too. Those pots are not normal series pots by the way. So their Zo isn't directly comparable to same nominal value series pots.
TKD 2511 inside
