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Must be something in the PC. If I pull out the RH interlink, that channel dies...
Ok there we go again, the distortion trough the LH channel.
It makes no difference if I disconnect the interlink at the Hypex side or DAC side.
When disconnected the distortion is gone...
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If we grab back to the closeup photo I took form the XLR connections, you see that I used twisted pairs from the SE of the IVY to the starpoint.
I just detached that ground wire from the IVY.
I heard a 'POP' and the distortion dissapeared.
When listening again sudenly the distortion came back.
I touched the RH grounding wire, still connected with one end to the star, with a plier and 'POP', discharged...
I think I will leave this ones out.
But does'nt the IVY need to be grounded?
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Do not ground the outputs. If you want to use s star gound, ground only the power supply gnd. You will be creating a ground loop otherwise. Justwirethe outputs to the isolated connectors.
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Ok thx!
I have them now disconnected. Let's see what happens :) I have good trust.
In between the distortions there was some perfect sound!
Do I also ground the HDBP's?
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It appeared again with the grounding wires from the IVY's tot the starpoint disconnected. Quite loud actually.
Just one touch to the LH starpoint with the plier and gone it is...
The setup is situated on the wooden plate. But the transformers are grounded. The HDBP's not.
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Just a question;
I have the housing of the XLR receptacle connected to the chassis.
I also have the Pin 1 connected to the chassis in the same star point.
The same go's for the Hypex.
In the interlink I have the Pin 1 and the housing bridged.
Will this cause any ground loops?
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Yes. Your connectors should be isolated from the chassis gnd. This means both the shell and Pin 1.
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Hm this confuses me. I have read dosens of short courses about balanced and the Pin 1 problem and in one thing they where all quite clear;
Use Pin 1 for the shielding and connect Pin 1 directly to chassis ground....
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I htink I solved the problem.
I cut the wire in the Hypex amplifier that double connected the housing of the XLR receptacle to the chassis....
It was a ordinary ground loop which came more and more obvious when I disconnected all other grounding wires.
So what first seemed like HF noise was actually a groundloop.. :)
Thanks for all the help!
In between al the distortion layed some beautifull sound and now I'm enjoying whole morning now without the distortion :d/
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Nice. You there have a very, very fine setup. Edited by user Saturday, April 7, 2012 6:42:08 AM(UTC)
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Hmmm the problem seems to persist..
I am using a medical netfilter and I'm beginning to suspect this one is passing trough noise to the chassis and from there to the interlinkshielding to the amplifier.....
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Highly unlikely. I'd start by cutting the interlink shielding from chassis ground. Lead it straight to the nCore module.
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So one problem is fixed and then the old problem start to play part again... Today there was again the distortion trough the LH speaker. If I remove the interlink of the LH channel the distortion is passed trough the RH speaker. It only seems to occur in the first half hour after starting the amplifiers up the new day. So when warming up I guess. When I tap one of the grounding points with a metallic like object the distortion dissapears suddenly. And it did not came back still today... I've made a drawing. "Schema 1 and 2" Shows a curved black wire. This is Pin 4 of J9 and is a Passive Ground... "Schema 2" Shows that I removed the Pin 1 of the XLR to Chassis GND on both the Hypex and DAC. This is my latest theory to prevent a groundloop. The two chassis are tight together only via Pin 1 of the LH interlink now... What I'm beginning to suspect is that the IVY is sending out a kind of signal which causes the Hypex to stress... It only occurs with this DAC connected and only at startup... Does someone has anything valuable to say about this? :) Thx! Jordo Jordo attached the following image(s):  Schema 1.png (22kb) downloaded 53 time(s). Schema 2.png (18kb) downloaded 49 time(s).You cannot view/download attachments. Try to login or register.
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Or will this probably work most effective? Connecting Pin 1 to the IVY  Edited by user Wednesday, April 18, 2012 5:03:52 AM(UTC)
| Reason: Not specified Jordo attached the following image(s): XLR IVY GND.png (14kb) downloaded 41 time(s).You cannot view/download attachments. Try to login or register.
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I would leave the chassis ground out of the picture all together, especially on the IVY side. Disconnecting the ground of one channel will not stop the ground loop, you would have to remove it for both channels.
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Ok, so no signal protection? :(
But than I will have to remove it also from the Hypex side or else I create a HF antenna...
The IVY is Grounded to the HDBP, is that correct?
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Quote:The IVY is Grounded to the HDBP, is that correct? Yes. You don;t really need signal protection, per se. They are differential, so any noise they pick up is cancelled in the differential input stage. This is the main advantage of differential (balanced) cabling.
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True... But why are they shielded anyway?
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I just bought a RCA Plug which I looped inside by connecting the inner Pin with the outer ring. This is to solve the locking problems with the COAX plug connected to the S/PDIF Module. I also disconnected the only Pin 1 left and now something strange happens.... When I touch the RCA Plug I made, the distortion can be heard trough both speakers. A Jitter kind of sound I guess. When I place the Pin 1 connection back to the Chassis this is solved.... Interesting. How can the COAX create a distortion anyway when the source selector is selected to another channel? EDIT: When I meassure between the two casings I meassure an alternating voltage of about 55 - 20 mV. When meassuring with the meter on AC I see a steady 1mV (this function cannot display mV AC). With the Pin 1 connected this is 0V EDIT 2: From the chassis of the DAC to EARTH I meassure a AC of 0,4V Edited by user Wednesday, April 18, 2012 8:53:54 AM(UTC)
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