Is this a good or a bad time to confess that I've been looking at switched-mode Dell laptop power supplies for the GM70 filament, on and off for most of today ?
I'm guessing it's a bad time to say this
Where did all my volts go ?
- IslandPink
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#16
"Once you find out ... the Circumstances ; then you can go out"
- slowmotion
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#18
Why not use double EI trafos and choke input + small cheating cap?
That said, I was collecting computer power supplies for years to use as filament supplies, but chickened out in the end.
That said, I was collecting computer power supplies for years to use as filament supplies, but chickened out in the end.
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#19
I use thrm on 833a. The valve itsellf is such a dominant influence on sound for good I get away with that. As does Phil.IslandPink wrote:Is this a good or a bad time to confess that I've been looking at switched-mode Dell laptop power supplies for the GM70 filament, on and off for most of today ?
I'm guessing it's a bad time to say this
I prefer otherwise to find a way to use ac .
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
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#20
By them I dont mean dell supplies I mean computer. It is a very beefy one I use.
"Two things are infinite, the universe and human stupidity, and I am not yet completely sure about the universe." – Albert Einstein
#21
10V at 10A - it would need to be a beefy supply for that
Although there are enough 120W 20V at 6A laptop supplies around so 10V at 10A is doable with a dc to dc converter as 90%+ efficiency is achievable..
J
Although there are enough 120W 20V at 6A laptop supplies around so 10V at 10A is doable with a dc to dc converter as 90%+ efficiency is achievable..
J
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#22
My 833a PSU is 12v @ 30A
I use R & C to get down to 10v
I use R & C to get down to 10v
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- IslandPink
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#24
I think the attraction became obvious also when I started collecting an order on RS and realised that two of the Epcos input caps ( 10,000u/40V, 8A ripple current ) for GM70 passive supplies would cost as much alone as two recent spec 19.5v SMPS supplies !
We have a few ideas up our sleeves about how to get rid of the residual noise ( which can be as low as 60mV at ~ 60kHz nowadays ) , such as using a virtual centre-tap , but obviously there may be some fun & games ( & a roll of mu-metal ? ) in controlling radiated EMF .
Anyway, Andrew I showed how nice things could sound with SMPS's , so it's worth trying .
We have a few ideas up our sleeves about how to get rid of the residual noise ( which can be as low as 60mV at ~ 60kHz nowadays ) , such as using a virtual centre-tap , but obviously there may be some fun & games ( & a roll of mu-metal ? ) in controlling radiated EMF .
Anyway, Andrew I showed how nice things could sound with SMPS's , so it's worth trying .
"Once you find out ... the Circumstances ; then you can go out"