Now I am looking for how to best ground my amp, please see attached picture showing one channel (only 0V lines are drawn): I have 2 transformers, 2 PSUs, 2 regulators and the actual amp board for one mono amplifier. The regulator for the power stage and the amp board both have 0V connections from their output stages, I marked them with "REF", and they have a normal GND connection at their input - which are not internally connected to the REF points. So I need to wire the REF points directly back to the 0V lines which is fine and known from the NAP circuits (the super-regulator for the front end does not have an extra REF connection). Now the question: where do I join the 0V lines of the 2 PSUs together: at the transformer, or after the smoothing caps?
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avoid noise of ground loop is difficult. on mine i have no buzz using on uptstage with JBL and Laptop, but with my first hifi system i have a little buzz ...
it must be said that it contains more devices and ground loops...
by connecting the amp on other wall socket the buzz is greatly diminished I think it's linked to the grounding with the other devices, anyway it works well like that
it must be said that it contains more devices and ground loops...
by connecting the amp on other wall socket the buzz is greatly diminished I think it's linked to the grounding with the other devices, anyway it works well like that
This is a different topic from the 0V layout inside a power amp, no...? In any case if signal-GND in the power amp is directly connected to earth you might get a loop because usually the ground connection is located in the source (at least in a Naim system). Either lift signal-GND in the power amp and/or ground it through the incoming signal-GND (but don't forget to care about safety). The GND-layout inside the power amp can cause noise (in my case it sounded just like faint white noise without buzz/hum), but now it's sorted (I think the reason was a bad path from the REF point in the power regulator). Here is a picture, suggestions are most welcome (cables are not dressed yet):
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Have you got EMI filter? I really hate your condition (changing socket&problem solved). I nearly always use "high impulse stopper" on the wall socket (I don't know what the name is). and I added simple EMI filter in my amp. Pre connected with only power amp.'s input. Pre's PSU not connected to ground. And ground connected with 10ohm resistor for only power amp. that's what I did in my work...
Another trick as, I connected my amp with 220v 500w voltage regulator (not amp or nap regulator). I don't think this is work. But, I had and used.
I have an EMI filter yes
but i do'nt use an hum break resistor
I think these are ground loops that are done with the ground
The problem is that I don't quite understand how to use a hum break resistor, indeed on the diagrams that I found it is noted in addition to the decoupling capacities, how exactly do you connect this resistor in your amp ?
but i do'nt use an hum break resistor
I think these are ground loops that are done with the ground
The problem is that I don't quite understand how to use a hum break resistor, indeed on the diagrams that I found it is noted in addition to the decoupling capacities, how exactly do you connect this resistor in your amp ?
To some extent, inserting a resistance in the safety ground connection probably works to reduce hum but from a safety POV, seems like a bad idea and may be illegal or nullify any other product warranties you may have in your country. Check first before tinkering with safety earth connections.
Take a look at this article, the critical safety issues and a proven amplifier humbreaker design/application: https://sound-au.com/earthing.htm
NB: I'm unsure of what your AC system is in Turkey, perhaps it resembles that in northern Europe (schuko plugs etc) where AC is a balanced 230VAC on 2 similar wires and a separate ground wire. This requires a different design to the one in the above link so don't try to use that design - its just for the warnings of what you are dealing with - danger!
NB: I'm unsure of what your AC system is in Turkey, perhaps it resembles that in northern Europe (schuko plugs etc) where AC is a balanced 230VAC on 2 similar wires and a separate ground wire. This requires a different design to the one in the above link so don't try to use that design - its just for the warnings of what you are dealing with - danger!
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Case must be connect to directly ground. That is usual design. And PSU's zero connect to ground with 10 ohms.
Case connection is as usual. is there any problem connect with 10ohm to ground? This adviced just like in https://sound-au.com/earthing.htm.
do you say in your countries earth and in my countries ground are different. If so I don't know the difference. My ground directly connected to earth. there is cupper wire in to the earth.
Case connection is as usual. is there any problem connect with 10ohm to ground? This adviced just like in https://sound-au.com/earthing.htm.
do you say in your countries earth and in my countries ground are different. If so I don't know the difference. My ground directly connected to earth. there is cupper wire in to the earth.
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A safety ground connection will likely be the same everywhere but the difference is the AC potentials and relationship between the so-called live(active) and neutral wires. The difference between some modern power systems is (Quote): "In Europe, there is a neutral connection in most countries, but the plug is designed so it can be swapped with the hot wire by simply rotating the plug. Therefore, the computer does not even know which of its input wires will end up connected to the neutral wire and which will be connected to the hot wire".
So there is uncertainty there and you may need to read the power company or government rules to be aware of what is or isn't a safe and legal connection and it may not be safe to use an earth breaker at all. Safety devices cut the power at the fuse box but they require a valid fault condition to work. If you interfere with the AC power or ground circuit in your amplifier, the fault condition may not trip the power supply and you are toast if you become that fault.
NB: Electrical safety is a legal matter and I'm not qualified to give advice, here or anywhere. All I'm saying is, when you tamper with circuit ground connections, check the details of what you propose to do against local safety rules and regulations to ensure you and anyone else who touches the amplifier or system are still protected physically and legally. 'Seems easy enough but this is not straightforward where different country regulations and power systems are concerned.
So there is uncertainty there and you may need to read the power company or government rules to be aware of what is or isn't a safe and legal connection and it may not be safe to use an earth breaker at all. Safety devices cut the power at the fuse box but they require a valid fault condition to work. If you interfere with the AC power or ground circuit in your amplifier, the fault condition may not trip the power supply and you are toast if you become that fault.
NB: Electrical safety is a legal matter and I'm not qualified to give advice, here or anywhere. All I'm saying is, when you tamper with circuit ground connections, check the details of what you propose to do against local safety rules and regulations to ensure you and anyone else who touches the amplifier or system are still protected physically and legally. 'Seems easy enough but this is not straightforward where different country regulations and power systems are concerned.
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BTW, the schematic you posted is lifted from Rod Elliott's ESP website as we can see. He and I are both in Australia and what he advises may, in principle, be universal to any domestic AC power supply but names, colour codes, supply voltages and safety devices etc. could all be different.
For what it's worth, Australian and New Zealand practice, names, voltages and wire colour codes are much the same as British (UK) practice, other than for hardware like their unique style appliance socket and plug.
For what it's worth, Australian and New Zealand practice, names, voltages and wire colour codes are much the same as British (UK) practice, other than for hardware like their unique style appliance socket and plug.
In my country active and neutral are not defined. If you connect the plug, you don't know which is active or neutral. it may change. ok. But, Ground (earth) is always ground. ""In Europe, there is a neutral connection in most countries, but the plug is designed so it can be swapped with the hot wire by simply rotating the plug." is true and not related.
My amp is kind of completed! I tried many grounding schemes (with some help from PFM) and finally settled on the one shown in attached pictures. It's a completely separate dual mono amp with four transformers: one per channel for the power stages, one with separate windings for the front ends, and one for the speaker protection modules. There is also a softstart module. The case is only 80mm high, it's a Dissipante 2U / 400mm (completely closed version), so it's very tightly stuffed, and the amp weights almost 20 kilos. The wiring looks a bit messy, but I tried to locate away the AC lines as far as possible from the DC and signal lines. It's not perfect, so if you have suggestions feel free to chime in. I have adjusted the power regulators to approx. +39,2 and -39,8 volts, the super regulators output 41,8 volts, and there is practically no DC offset. The sound is very smooth, natural, has great emotional impact and the timbre is neutral. The bass is extremely strong and clean even with small bookshelf speakers. Bias is set to 7,2mV (across both emitter resistors): is that too low...?
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I made an ncc200 with the front end modules according to the Avondale ground plan and from the first listen no background noise or hum.Looking at your complex realization I notice that the layout does not clearly separate the power supply part from the circuits . The 220v outlet is symmetrical and in between the two inputs so the 220v takes a long path before the transformers. These are details I know ,however .
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You are right, but I didn't find a way to separate them further in that case. I don't hear hum/buzz/noise though, so I guess it's fine, but the version with the original Naim boards sounds vastly better: same layout but without the extra transformer for the front end regulators. When I had them setup with flying crocodile clip wires the regulated amp sounded better, but assembled in the case the Naim sounds better by far. Surely the distance between the AC and the signal lines/circuits plays a role... BTW the Dissipante case doesn't fit together without bending the front and back panels: the heat sink elements are too long, there are small gaps everywhere, is that also the case with your case?