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Old 19th June 2004, 08:05 PM   #21
alk is offline alk  Europe
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That amp is going to be fat....the one in the pic is for 250V, i wonder the size of yours
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Old 19th June 2004, 08:11 PM   #22
G is offline G  United States
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Quote:
Originally posted by Layberinthius
I always thought this:

AC VOLTAGE:

The sum of the DC and Peak AC voltage applied to the capacitor should not exceed the rated DC voltage, nor should the RMS voltage exceed the Corona Start Voltage.

http://www.americancapacitor.com/Tech.htm

And I always knew this:

1.42 DCV per ACV

Working voltage (Wvdc, Wvac):

The maximum continuous voltage that should be applied to a capacitor. Rated voltages for DC and AC operation are usually not the same.



Thanks G however I need proof to both proove to myself and to my amplifier, I'm not about to waste many hundreds of dollars to buy high-capacitance PIO caps for my 50watt/channel just so all of the AC ripple gets passed through... :\

They're 25 PIO capacitors rated at 17.5uF of 440vAC each... I did good? sure as hell I did!! at 130uF/channel filtering!! all PIO

What type of circuit are we talking about? I'm thinking you should only need about ten of them for a satisfactory power supply.
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Old 19th June 2004, 10:28 PM   #23
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See for yourself.
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Old 19th June 2004, 10:51 PM   #24
G is offline G  United States
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Quote:
Originally posted by Layberinthius
See for yourself.

I mean what type of amplifier are you building? Single ended? Push Pull?
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Old 19th June 2004, 10:53 PM   #25
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They aren't small :P

The plan is to use about 5 of these each CHANNEL like this:

C1 is two 660vAC 8uF PIO capacitors in parallel
C2 is one 660vAC 8uF PIO capacitor and one 17.5uF 440vAC capacitor.
C3 is two 440vAC 17.5uF PIO capacitor.
C4 is two 440vAC 17.5uF PIO capacitor.

Total ma from the trafo is 230mA, total load is 230mA but varies greatly due to the amplifier being P-P.
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Old 19th June 2004, 10:54 PM   #26
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The simulation results as it stands.

The idea is to place 5 of these 17.5uF caps in a 525vDC power supply and see if I would benefit from any addition of capacitors wether it be in position C1-C4..

But eventually, ultimatley, finally... the idea is to use 5 per channel for B+ then use another 4 for each channel -80v Bias supply.

I am welcome to any suggestions or warnings
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Old 19th June 2004, 11:19 PM   #27
G is offline G  United States
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I'm not asking for the schematic. I'm just asking what type of circuit it is. Is it a big secret?
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Old 19th June 2004, 11:27 PM   #28
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NO I thought I said the circuit type...

Quote:
Total ma from the trafo is 230mA, total load is 230mA but varies greatly due to the amplifier being P-P.
Push pull, I'll tell you the rest though.. KT88:VDV KT88

While some people don't do work in the morning, I do...

So mind me if I jump on here and don't give a reply for an hour or two.
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Old 19th June 2004, 11:41 PM   #29
316a is offline 316a  England
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Quote:
Originally posted by Layberinthius
NO I thought I said the circuit type...



Push pull, I'll tell you the rest though.. KT88:VDV KT88

Hello ,
Thats a copy of the Hafler and Keroes version of the Williamson . Plenty of scope for improvement and modifications but I'd be very careful with regards to the size and layout of your chassis , especially with all those caps . It may be an idea to build separate chassis for the psu and amplifier stage and link the two with an unbilical cable . Otherwise build monoblocks .

cheers

316a
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Old 20th June 2004, 12:08 AM   #30
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Quote:
Hello , Thats a copy of the Hafler and Keroes version of the Williamson . Plenty of scope for improvement and modifications but I'd be very careful with regards to the size and layout of your chassis , especially with all those caps . It may be an idea to build separate chassis for the psu and amplifier stage and link the two with an unbilical cable . Otherwise build monoblocks . cheers 316a
First off thanks for the reply, second:

Yes the whole project is based upon constructing two chassis for the PSU for each channel and I have about 4 by 2 foot of desk space for the two PSU's alone, the amp has the same just above it for two amp chassis, soo monoblock with seperate PSU and Amp chassis.

So I'm certianly not running out of space to put it however I may need to consider making the pair of PSU chassis a heavy Aluminium construct and the amplifier itself for each channel light a light Aluminium construct so I can actually do the modifications in moderate not-back breaking pain whenever I pick a side up!
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