Somewhere, anyway. It's just not necessarily easy to determine where exactly the connection is running. And that stuff does make a difference. I'd assume both are tied to star ground, which in turn is tied to PCIe and power ground. If instead they had just connected audio ground to slot bracket at the outputs, any ground loop currents coming from PCIe or power ground would be running across audio ground and make quite a racket. You would be very hard-pressed to tell both variations apart with a multimeter!
This grounding stuff is a royal pain, I know.
Just run them physically close or even twist them. You want minimum ground loop area. (This won't help if part of the loop is shared with noisy return currents and those are the actual problem, but at least it won't try to act like an antenna too much.)
I asked goodguys whether he uses power transformers. They might help with the hum/ground loops without you having to use signal trafos
He says Yes, i am using a 300va 35v-0-35v torodial power transformer with each quad amp
You use one per amp, or possibly a 115v transformer for all three.
To see if it would help, check continuity from the ground out of the SMPS to the power ground input of the SMPS. Continuity means there can be a ground loop there. If not, I doubt a transformer would help
You use one per amp, or possibly a 115v transformer for all three.
To see if it would help, check continuity from the ground out of the SMPS to the power ground input of the SMPS. Continuity means there can be a ground loop there. If not, I doubt a transformer would help
There is continuity between SMPS ground... ground loops everywhere dag nabit!
Quick question about about power transformers, as I've never used one yet:
Using this one as an example, does that mean each output has 50 watt output or is the 50VA the total wattage for both outputs?
I've also read that many people have taped up their slot brackets to break ground grounds loops. Do you guys think there's any danger in that?
Quick question about about power transformers, as I've never used one yet:
Using this one as an example, does that mean each output has 50 watt output or is the 50VA the total wattage for both outputs?
I've also read that many people have taped up their slot brackets to break ground grounds loops. Do you guys think there's any danger in that?
The listed RMS voltage is 24V and current is 1A. Power = V*I = 24 Watts. The transformer is rated for 50 VA continuous, which implies that 50 Watts is the total continuous voltage for both outputs together (50/2 = 25).
What I am not sure of is what happens if you add capacitors to get the voltage up to peak, 24*1.414V. Maybe wrong, but I think in that case you would have to have lower current so that Power is still less than 25VA for each output.
What I am not sure of is what happens if you add capacitors to get the voltage up to peak, 24*1.414V. Maybe wrong, but I think in that case you would have to have lower current so that Power is still less than 25VA for each output.
So a low-impedance tie? Not good in this case. Some notebook PSU designs are smart enough to use something like 1 kOhm || unknown cap at least.
At this point you can probably understand why some people consider unbalanced audio essentially broken these days. (Balanced, assuming it's done correctly, may have pretty high rejection for all things common-mode.)
Probably not (things still connect to power supply ground), but I also doubt it'll help if your ground loop is running from your amp to PC power supply ground over the power supply connection.
Star ground to the power supply of the amplifier together with thermistor à la Firstwatt F5 helped me with my noisy tube amp. Check if your amp is grounded to the chassie in several points. You want it connected to only one point close to the power cable. I am also working on a contraption to filter out the last of the noise from the computer. Will be finished in a week when I get the part.
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Thanks for the replies guys. I'm still waiting on Asus - darn near a month now.
Poking around with my onboard 5.1 sound I can confirm a pretty harsh ground loop tied to the SMPS ground, like sgrossklass said.
I would love to follow vladimirb0b's advice and use separate transformers but I'm very limited on space and was thinking of using just one large transformer and sharing it's power among the amp modules. Before I move on that plan, do you guys forsee any more ground loop issues, maybe between the amps if they share one transformer power supply?
Poking around with my onboard 5.1 sound I can confirm a pretty harsh ground loop tied to the SMPS ground, like sgrossklass said.
I would love to follow vladimirb0b's advice and use separate transformers but I'm very limited on space and was thinking of using just one large transformer and sharing it's power among the amp modules. Before I move on that plan, do you guys forsee any more ground loop issues, maybe between the amps if they share one transformer power supply?
This might work for you AN-15435 - 1500VA 432V Transformer - AnTek Products Corp
Don't know what voltage your amps need. Also I would email them to make sure it is 4x32V
Don't know what voltage your amps need. Also I would email them to make sure it is 4x32V
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