Correct way for PSU?

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What's the correct way to tracks on power supply PCB with full 8 diodes regulator?!

1. Common tracks for GND of 2 haft wave. Star ground is this track, not the point (the entire length of the track). It's will connect pins (+), (-) of caps and are the GND of circuits.
This is usual way. With < 8 total caps, it's good. Reference power supply sells at DIYAUDIO Store use it. But with the very many caps, the length of track is the problem. The track's resistance make bad effects.

2. Separately tracks and connect all at the star ground.

3. Use ''T-Ground''. Ex: On positive rail, separately track for cap banks by 1 track. GND for cuicuits by 1 separately track. It's common GND. All track connect at star point. Similar with negative rail.

So, (2) same way with (3).

What's the best way? I think (3). Anybody can suggest me.
 
You description is vauge. Can you draw out what you mean? Typically after the rectifier you have a set of filter caps to which each gnd return goes to the centertap. Then you may have a small resistor to a capacitor bank that powers the amplifier. The gnd returns for these are seperate paths to the centertap forming the star gnd point. The concept is to seperate the charging pulses from the power transformer from the high current pulses returning from the speaker.
 
Ok, i'm attack the files.

In left, it's usual/popular and simply in layout. If you have total <8 caps, the star ground is the length of common track, its sort. The track resistance is not significant. Circuit's good.

Right, i think call it by ''T-ground''. Separate track connect caps bank and return at star point. Both pos. & neg. so. GND return from circuits, Speakers are connect at star point too.

I'm worry because if you use too many caps, the track length would be too large, the resistance is too high. (1) way is simply in layout more than (2), (3).
My plan is use total 20 caps in main supply.

If you are, you will choose?
 

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The left-hand circuit is not too bad, apart from the labelling. The ground bus in the PSU should not be labelled 'main star ground'; it isn't a star and it isn't main.

The right-hand one will have serious buzz problems.

The proper way to do it is to use a ground bus in the PSU, as in your left-hand circuit, but do not make even the clean end of the PSU the signal star ground. Instead, have a separate star ground which the PSU ground also connects to. This is spelled out in lot of places, so I cant imagine why people still keep getting it wrong.
 
The left-hand circuit is not too bad, apart from the labelling. The ground bus in the PSU should not be labelled 'main star ground'; it isn't a star and it isn't main.

The right-hand one will have serious buzz problems.

The proper way to do it is to use a ground bus in the PSU, as in your left-hand circuit, but do not make even the clean end of the PSU the signal star ground. Instead, have a separate star ground which the PSU ground also connects to. This is spelled out in lot of places, so I cant imagine why people still keep getting it wrong.

I don't understand exactly what you want say to me. If you can, please use a pic to describe it.
 
Yeah, that is what I meant :) This is the power supply board I have used for a gainclone, no hum problems. The bridge rectifier and transformer centre tap connect on the left. The star ground point is just left of the fuses, between the capacitors.
 

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@Walkalone: I think what they are telling you is to keep the common point of the rectifiers, away from the place where the speaker return (speaker ground), and other signal grounds are connected together. "star" ground is just a word, a label that people can disagree on...

So, imagine a long circuit board, with rectifiers, or rectifier connections at one end. Then, a double row of electrolytic capacitors, like the layout above. 2-4-8... As many as it takes for your project. Perhaps some small resistors to help filter the AC ripple. At the opposite end of the circuit board, a connection or connections for signal grounds, speaker returns, control circuits etc. In between, a medium trace which connects the common point of the two rectifiers, to the common point of all the other ground connections.

It might also help to post the intended use of the power supply, you could get better advice if you do.
 
Ok, thanks everybody! I was understand what you are tell me.

I found Magtech Amplifier - the Hi-end equipment (from Sanders Sound System). It's seem like layout PSU with ''T-ground'' (3). With 4 filter caps per rail. Chassis ground connected at star ground.

It's means the (3) way was not bad. I wonder why, how they do it?
 

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Assuming what you say is true, then a poor design can sometimes be improved by over-engineering. For example, a ground connection carrying charging pulses in series with signal voltages can be improved by making it short and thick so it has low impedance. The correct solution is to separate charging pulses from signals, then you can use thinner conductors.

Don't assume that popular, highly praised commercial equipment (even so-called 'high end') is competently designed. Sometimes it is; sometimes it isn't. In fact, I would say that one of the signs that someone is beginning to really understand electronics is when he can spot errors in some commercial circuits.
 
It's means the (3) way was not bad. I wonder why, how they do it?
Different approach from what is usually recommended here... two layer PCB, large and wide, with big power and ground planes. More like what you would see in industrial application. Also seems to be an extra skinny trace to balance something else in the circuit. Most people who post here, assume single layer boards.
 
Bonsai - a member of our forum. He have a project, they're look very professional, called is ''e-amp''. Their PSU is used ''T-ground'' that i said.
http://hifisonix.com/wordpress/wp-content/uploads/2011/03/The_e-Amp_V2.03.pdf

I'm really confused. What's the best way?

My plan is create a PSU with 8 ultra fast diodes (Ixys DSEI60-02A) or general diodes like GBPC3504 and about 20 filter caps for my next project. It's not necessary monoblock, although they are better.
 
''T-ground'' is simply called by me. Maybe its means that the ground connection of the caps, circuits by separate tracks. So formed like the ''T'' letter.
I think, with ''T-ground'' many caps each pos. rail or neg. rail would be equivalent to only one cap.

I used the usual way, with total under 8 filter caps. They're good and simple in Layout.
 
Connect the -ve of upper bridge to C1.
Connect the +ve of lower bridge to C2.
Connect Cpos.n to Cneg.n
Connect this last Zero Volts link to the MAG.

You almost have a MAG in your diagram. Look at where Speakers Return meets Signal GND and nearly meets Main circuits GND
 
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