I have missed the prefix when I was replying on the fly off my IPhone... My bad
As far as the ESR goes i have no idea what the actual spec is but i was told by the seller they are very very low ESR.
As stated above, sufficiently low ESR is very easy to obtain. There is no purpose for "very very low ESR" caps, or massively oversized banks of them, anywhere in audio. By and large, the limiting factor is line frequency ripple, typically 24000uF volt per amp. At 50V, 10A, 4700uF is enough. More and you significantly worsen the power input characteristics.
Tim
Tim
Well...
gave up on this idea and just bought these. 4 of them should do running 2 for each toroid. Also ordered 8 x 1500uF 100V Chemi-Con KMH caps and have 2 more dozen .1uF 400V film caps comming as well. Now just gotta find some suitable T0220 Rectifiers, which shouldn't be hard. Probably looking at 20-30A units.
gave up on this idea and just bought these. 4 of them should do running 2 for each toroid. Also ordered 8 x 1500uF 100V Chemi-Con KMH caps and have 2 more dozen .1uF 400V film caps comming as well. Now just gotta find some suitable T0220 Rectifiers, which shouldn't be hard. Probably looking at 20-30A units.
Time to bring back this thread form the dead 
Looking at rectifiers and dunno whetever to jump to Schottky diodes or just high speed slow recovery types...
The one im currently stuck on is MBR40250 and any other sugestion is welcome...
As far as the boards go, they are still stuck in customs ( its been 2.5 weeks now since they had them ) and hopeing to get them by tomorrow !!
Looking at rectifiers and dunno whetever to jump to Schottky diodes or just high speed slow recovery types...
The one im currently stuck on is MBR40250 and any other sugestion is welcome...
As far as the boards go, they are still stuck in customs ( its been 2.5 weeks now since they had them ) and hopeing to get them by tomorrow !!
After going to all this trouble to get a low Z power supply make sure the wiring from the power supply to the load is either a sandwich bus bar or a twisted set of wires otherwise the inductance of the loop enclosed by the wiring will appear as ESL. FWIW I have a 1Kva C core transformer for a subwoofer power supply with 20000uf per rail filtering Output voltage is +/-71V no load dropping to 67V @ 700W with 0.5V RMS ripple, The single 3504 bridge rectifier barely gets warm and even after an hour at 700W the transformer is barely warm, This should give you an idea of what to expect. As for rectifiers any diode will work fine the Z of the filter capacitors at high frequency is so low compared to the Z of the transformers and leads that any reverse recovery charge will just get soaked up in the Z of the AC circuit. Use fast soft recovery diodes if you must but I have never seen any diode switching noise on the rails of a 50Hz power supply, poor wiring or pcb layout would have a much bigger influence.
Boards showed up today
Started "stuffin" them right away with parts i had on hand
Here's the end result
Still missing :
R1 - R 10 : 1 ohm 3W 5% - 32 pieces
R11,R12 : 2.2K 3w 5% - 8 pieces
D1 - D4 : MUR2020 - 16 pieces
D5 : 1N4007 - 0 Pcs
C10 : 10uF 63V – 4 Pcs
R20 : 3.3K 1/2W if the AC input is 24Vx2
LED : 3mm green or red LED
C7, C8 : 0.1uF 100V - 0 pcs
C1 – C6 : 4700uF – 15000uF 50V or 63V – 0 pcs
Started "stuffin" them right away with parts i had on hand
Here's the end result
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Still missing :
R1 - R 10 : 1 ohm 3W 5% - 32 pieces
R11,R12 : 2.2K 3w 5% - 8 pieces
D1 - D4 : MUR2020 - 16 pieces
D5 : 1N4007 - 0 Pcs
C10 : 10uF 63V – 4 Pcs
R20 : 3.3K 1/2W if the AC input is 24Vx2
LED : 3mm green or red LED
C7, C8 : 0.1uF 100V - 0 pcs
C1 – C6 : 4700uF – 15000uF 50V or 63V – 0 pcs
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The boards in your posted pics do not look like the one's you ordered.
What gives?
If you want a REALLY STIFF supply, then this one should fit the bill.
90x330uF = 29,700uF with ULTRA-LOW nano-ohm ESR
An externally hosted image should be here but it was not working when we last tested it.
usually, if you want better regulation 2 transformers instead of 1 bigger one is not the way to go. For the cost of 2 small ones you will get 1 bigger one with far better regulation given the same load. Same applies if you compare weigth. This is especially true for transformers below and up to about 1kVA.
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