| brsanko |
| anybody now where I can find some good info on how to design a SS power supply for a tube amp. |
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| richwalters |
Hi there----what's the reason for SS PSu' ?? I presume you really imply "standard linear regulator" configuration and not switchmode ?
For a brouse have a peer at triode electronics website and brouse at Steve Bench's box.
What power req do you have in mind ?
rich |
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| brsanko |
| well I want to build my own amplifiers and I just want some general info on how to design power supplies I've been reading Bruce rosenblitz's beginers guide to tube audio design and his chapter on ps was kinda vauge. no advice on how to pick rectifiers or on what size caps to use ect would really like a lice in depth tutorial |
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| Sch3mat1c |
Meh. Caps are 2-10mF per ampere for SS, tube amps usually take it a good bit leaner (we have choke filters after all!), say 1mF per amp. So 100mA would use 100uF, which is a reasonable value for 60Hz. For 50Hz technically you'll want slightly more (60/50ths more to be exact :p ), but caps are wide enough in value anyway. (Note that most tube rectifiers cannot handle more than 40uF, be sure to stay within limits!) And you won't notice the difference with a good bit of choking. Caps also need to be rated at the maximum expected voltage, which would be maybe 1.5 times the unrectified AC voltage.
Rectifiers, just grab some 1N4007s or similar diode of adequate current and voltage rating. No need for HEXFREDs or anything (though saying so will earn me some flames. Bring it on).
Tim |
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| fdegrove |
Hi,
| quote: | | say 1mF per amp. So 100mA would use 100uF, |
Don't you mean 1µF per mA?
| quote: | | Rectifiers, just grab some 1N4007s or similar diode of adequate current and voltage rating. No need for HEXFREDs or anything (though saying so will earn me some flames. Bring it on). |
You're asking for it but I'll refrain given the time of the year...
Oh, use good quality caps after the chokes...Those are the ones you'll be listening to.
As for SS regulators..BLECH,:dead: ...They're the first to go south in high voltage rails and you'll hear their sonic fingerprint anyway...Could as well stick to solid state throughout in the first place.
Just my opinion...
Cheers,;) |
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| ShiFtY |
One thing I have found useful is to put a 0.082uF 3KV ceramic cap across the transformer secondary (HT). This cut down a lot of noise in the amp.
Edit: I use a pair of bog standard IN5404 (3000V 3A) in my PSU, hasn't failed yet. UF4007 failed to a short, blowing the fuses. ow. |
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| Sch3mat1c |
Erm...5404 is 400V. :eek: 5407 or '8 is the 1kV.
Frank: same difference :clown: (as much as I cringe to use that expression).
Tim |
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| ShiFtY |
erm you are right! Whoa, maybe I should change em for higher PIV ratings... My B+ is only 380V, but :bigeyes:
Wonder why I thought they were 3000V PIV? hmmm
Edit: actually just checked and they are IN5408s. Phew. |
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| fdegrove |
Hi,
| quote: | | Frank: same difference (as much as I cringe to use that expression). |
As much as I hate to admit a mistake you mean?
Cheers, :smash: |
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| Sch3mat1c |
Errr... you know what an "mF" is, don't you? It's proper use of SI standard terms. Check it out.
Tim |
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| dhaen |
| It's Frank's "American" side coming out :D |
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| richwalters |
Someone's taking me on here.....come on.......who says SS isn't on for HV amp power supplies?.....HP have been using this for decades in their test equipment and so have I and not one has come back due to duff PSU's. Do the physics and there's nothing wrong with them. As for SS regies changing the sound sonically, if they are put in the right place <simply.. No>
rich |
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| miguel2 |
Well, I made a really sweet psu for a preamp sometime ago. Don´t recall the rectifiers, but I used after a 4.7uF film, 10k resistor, 4.7uF film and a pass transistor made the rest. Very nice indeed. And a 4.7uF near the tubes.
Miguel |
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| Sch3mat1c |
| quote: | Originally posted by richwalters
Someone's taking me on here.....come on.......who says SS isn't on for HV amp power supplies?.....HP have been using this for decades in their test equipment and so have I and not one has come back due to duff PSU's. Do the physics and there's nothing wrong with them. As for SS regies changing the sound sonically, if they are put in the right place <simply.. No> |
Well, I have been smelling something odd in Frank's direction...
Come on Frank, don't bogart it..... ;)
Tim |
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| fdegrove |
Hi,
| quote: | | Come on Frank, don't bogart it..... |
I did say:
O.K.....I'll leave you to it if you promise me not to use those mF symbols...:smash:
Cheers,;) |
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| dhaen |
Designing PSU's for valve's is no different than for anything else. Only the component values vary, as described by the previous posters.
Perhaps the main change is that chokes become practical, both in LC and CLC arrangements.
Here is a link to the most commonly used and free PS simulator:
PSUD2 Play with the simulator until you feel comfortable. It'll do SS and valve recifiers.
If you have a PC it'll run. If you have a Mac, contact me.
IMO Valve rectifiers win, if only because they've got built-in soft-start ;) |
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