Here is a question that has been bugging me. You want to beef up your power supply, so you put some caps in parallel to the main filter caps
However you only put in a single line to the capacitors from the bridge, in other words you CUT THE LINES at point "CUT" indicated in the picture.
Would this be a problem, it seems that there may be conflict with current going into the lower cap bank and the need for current to come out of the cap bank, as current can only flow in one direction at a time. If the load needs current when the caps are charging the caps will not be able to provide it because current can only go one way-- and its flowing in. Or will current stop going in and come out naturally???
As you can see I am confused on this.
However you only put in a single line to the capacitors from the bridge, in other words you CUT THE LINES at point "CUT" indicated in the picture.
Would this be a problem, it seems that there may be conflict with current going into the lower cap bank and the need for current to come out of the cap bank, as current can only flow in one direction at a time. If the load needs current when the caps are charging the caps will not be able to provide it because current can only go one way-- and its flowing in. Or will current stop going in and come out naturally???
As you can see I am confused on this.
Attachments
Hi Lgreen,
have a look at Choco's PDF,
http://www.diyaudio.com/forums/attachment.php?s=&postid=948118&stamp=1151245617
It shows
It's all in the interests of keeping the high value peak charging currents away from the amplifier.
have a look at Choco's PDF,
http://www.diyaudio.com/forums/attachment.php?s=&postid=948118&stamp=1151245617
It shows
Your additional caps should be tightly coupled to the rectifier, not hung way towards the amp.Tight coupling of transformer to rectifier to first stage smoothing.
Link PSU common to star ground.
Bring clean and dirty grounds to star ground.
Keep decoupling and speaker return separate from clean ground.
It's all in the interests of keeping the high value peak charging currents away from the amplifier.
Huh?
I don't think Iget it. I realize caps should be close to diodes and away from amp, and all that star groundng makes my head hurt.
I have some room to add a bank of caps far away from each (like 3 inches), figure it cannot hurt or if it does I can remove the extra caps.
The issue is whether I can just use 3 wires or whether I need 5 or 6 wires to/from the cap bank.
I don't think Iget it. I realize caps should be close to diodes and away from amp, and all that star groundng makes my head hurt.
I have some room to add a bank of caps far away from each (like 3 inches), figure it cannot hurt or if it does I can remove the extra caps.
The issue is whether I can just use 3 wires or whether I need 5 or 6 wires to/from the cap bank.
lgreen said:If the load needs current when the caps are charging the caps will not be able to provide it because current can only go one way-- and its flowing in. Or will current stop going in and come out naturally???
As you can see I am confused on this.
Say what you will but reading and understanding some basic electronics/physics books is a must. No amount of forum browsing can substitute this.
3 wires will do you fine.
You just need the 3 wires.The issue is whether I can just use 3 wires or whether I need 5 or 6 wires to/from the cap bank.
You are getting confused about where the currents flow and how. If the caps are connected with thick wires it doesn't matter so much what route the current takes EXCEPT at high frequencies.
All wires have inductance. You need to read up about the effects of inductance at high frequencies. This will answer questions like whether the caps should be close to the rect or close to the amplifiers or both or neither. It is generally best to make the wires between the sets of caps as short as possible, and to put them in a chain: rectifier to 1st cap, 1st cap to 2nd cap, 2nd cap to amplifier, repeat for the opposite rail.
My immediate question for you is why you want to add more caps? Eg: adding more caps without changing anything else is no guarantee of making the circuit sound more powerful - it may degrade the sound. You must also check that the rectifier has enough current rating to charge the extra caps.
Hi Trader
The charging pulses to the second set of caps must also be kept in the tight loop around the rectifier & transformer.
Do not connect the extra caps further down stream where the charging voltage drop will contaminate the lower current wires to and from the amp power circuits.
Lgreen,
have you had a look at Choco's sketch? It is very simple to follow.
I don't agree.it doesn't matter so much what route the current takes EXCEPT at high frequencies.
The charging pulses to the second set of caps must also be kept in the tight loop around the rectifier & transformer.
Do not connect the extra caps further down stream where the charging voltage drop will contaminate the lower current wires to and from the amp power circuits.
Lgreen,
have you had a look at Choco's sketch? It is very simple to follow.
hmmm....
OK, to explain it one more time. I have a working power supply and-
- I want to add capacitance.
- I don't have any room in the case except to put them on the top cover. Like This.
- So I connected them up like shown in the diagram and if you really want to see the whole thing, its here.
- the stuff on the bottom of the diagram are the rooftop caps, connected as shown
OK or not?
OK, to explain it one more time. I have a working power supply and-
- I want to add capacitance.
- I don't have any room in the case except to put them on the top cover. Like This.
- So I connected them up like shown in the diagram and if you really want to see the whole thing, its here.
- the stuff on the bottom of the diagram are the rooftop caps, connected as shown
OK or not?
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