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In the Forum: Audio Discussions
In the Thread: How to get a LOT of SET power.

Post Subject: D'n'B v2Posted by N-set on: 3/31/2011

Here is another, simplified assault after some rethink and PSUD simulations.
Rectifier: 3x1.2kV SiC per phase should do the job, actually 2 would do, but I'd prefer
to be safe. Bridge I don't want, as there would be 6 not 3 diodes switching
1750V. 1.2kV 10A SiC's. There are 1.7kV SiC's but in raw wafers which I have no
idea how to handle.

The caps: actually why not stacking electrolyts? ESR worsens, so does the impulse
power transfer, but maybe one could still reasonably bypass at 2kV?. Nichicon has introduced
630V elco's, so hopefully 550V ones will be cheaper (or dirt cheap if bought
directly where made--in China). 500uF @ 1.4kV stores as much as 15.000
@ 250V. It also gives a reasonable damping to the LC cell (low DCR LC supplies are
notoriously resonant). The first cap, let it be PiO to save on space a bit.
The resulting ripple @ second cap is around 70mV according to sims and 40mV if the
first cap is 20uF (which I don't have).

Heating is a pain now. Due to the huge currents it should be DC I think, which adds to the
complexity and weight. Ideally it should be a CCS, but let's try to simulate it with chokes.
Don't get fooled by small values.
10mH@10A stores as much energy as 100H @100mA if that matters...

I was looking for another driver. SV572-30 would be an option (one can still get them
for $80...) but it has higher Rp and mu=30 is a bit low. 812 is another one, but cannot withsand
100mA -8-10V biased, IIRC. I'd stay with 833 at the moment although it's 3.5k Rp may kill the idea.
Audiopedophiles would be impressed anyway, let them listen to a 833 RIAA!

I think it would not be much bigger than Wavac SH-833. And there are people
who somehow think they need 3 of them per channel:

http://forum.audiogon.com/cgi-bin/fr.pl?vaslt&1104825435&read&keyw&zzwavac%20audio%20sh-833

let their gods connect them to the hot 833 plates, so perhaps in light of that idiocy the whole
idea of 833 bass is not that irrational as it may seem? The narrow questions are within 10-100Hz,
projecting to ...Hz-...Hz, I agree,
but maybe an unheard trace of the voice of god resides there?

PS Some idea on how to mount the rectifiers: take a hammond die cast alu box, make 2 big holes and put good
multi kV groomets, put the rectifiers+resitors there
and fill everything with silicone. Then close and forget! The box will shield the RF a bit
(one can go delux and wrap the box with Cu foil, which is easy).

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