[Amps] How light can you make a 500W amplifier?

[Rich]

>Did you calculate (yet) the regulation/ripple of using such a multipler
>using the array of 560 uF capacitors, assuming, say, a 500mA load current?

**  I don't know how to go about calculating the ripple or how to size 
the capacitors for a quadrupler ps.  My estimate of 8 caps per quadrupler 
assumed that some seriesing and paralleling will be needed.  Any 
suggestions from you would be appreciated on how to calculate the C 
values for such a supply.   Perhaps breadboarding such a supply would be 
enlightening?    Designing an amplifier for the supply will require 
floating both the positive and negative hv circuitry from chassis ground 
-- much as is the case with grounded-screen 8170/8171 and 8281 Class AB1 
amplifiers.   This will require a handfull of 3kV bypasas caps and a 
filament transformer that can withstand 1500vdc.  

cheers, Steve

>I haven't, but will.  Now, I have to go look for the formula, which I
>haven't used in about 20 years!  -Steve, WB2WIK/6

>> -----Original Message-----
>> From:	Rich [SMTP:2@vc.net]
>> Sent:	Tuesday, October 15, 2002 7:39 AM
>> To:	Steve Katz
>> Subject:	RE: [Amps] How light can you make a 500W amplifier?
>> 
>> Panasonic/Matsushita aluminum electrolytic # P7420, 560uF, 400v  is 35mm 
>> dia by 50mm long.    The current rating is 3A-rms.  My guess on  weight 
>> is c. 60g each.  A quadrupler would require c. 8 such capacitors.  Two 
>> quadruplers in series would require c. 16 such caps and produce c. 
>> 2400vdc out @240vac in.  The cost is c. $9 per cap for a total of c. $150 
>> including rectifiers.  Joe Jennings built a similar lightweight ps for a 
>> portable linear amplifier some 40-years ago.  
>> 
>> >I don't believe a 1 kg power supply using a 6x multiplier at 50 Hz or 60
>> Hz
>> >is possible, at the current level required.  Unless someone invents
>> nearly
>> >zero-mass large-value capacitors required by the multiplier, seems to me
>> a
>> >6x multiplier at any current level beyond a few mA is an inefficient
>> power
>> >conversion method at 60 Hz line frequencies.
>> >
>> >WB2WIK/6
>> >
>> >"If everything seems under control, you're just not going fast enough." -
>> >Mario Andretti
>> >
>> >> -----Original Message-----
>> >> From:	Rich [SMTP:2@vc.net]
>> >> Sent:	Tuesday, October 15, 2002 2:08 AM
>> >> To:	Alan Ibbetson; AMPS
>> >> Subject:	Re: [Amps] How light can you make a 500W amplifier?
>> >> 
>> >> The lightest weight power supply would likely be a voltage-multiplier 
>> >> type operating direct from the electric mains.  With a x6 V multiplier 
>> >> and 230V mains, c. 1600vdc could be produced for c, 1kg in ps weight.  
>> >> With a 4cx800, 1600v would produce >500w.  A foolproof screen supply 
>> >> could be derived from the anode supply using a zener-string shunt 
>> >> regulator.   My guess is thar a total weight of 4kg should be do-able