Is it even Logical/safe to increase/mix and match in series or parallel networks of different values upwards to what 2-4x original amounts?
Debating on trying something/increasing/mixing but I know... there is some increased Risks/strain on rectifier/PSU right with Charge up/inrush.
Mainly Curious if I could get a bit cleaner/filtered/tighter sound...noticeable ghosting would go away etc.
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This is the kinda stuff I need to ask because it feels like with my Uncertainty, I'm going to do something that will/can cause some Fireworks etc haha
The value tolerance on "older" elctrolytic capacitor value was such that you could actually have X2 or X 1/2 what was written on the side anyway. THat sort of change will barely be noticable.
I tend to buy a bag of 22uF 450V Panasonic ED and just use 2, 3 , 4 etc in parallel till I like the sound.
KOC has a section on setting main filter cap size in one of the TUT books. Can't remember what criteria he used, need to go back and read it again.
If NOT using a tube rectifier then there are no real circuit safety/reliability implications in going up by a factor of even X10. More should give a tighter (more HiFi) sound.
If using a tube rectifier you MUST stick to the maximum C1 spec for the rectifier.
Cheers,
Ian
I tend to buy a bag of 22uF 450V Panasonic ED and just use 2, 3 , 4 etc in parallel till I like the sound.
KOC has a section on setting main filter cap size in one of the TUT books. Can't remember what criteria he used, need to go back and read it again.
If NOT using a tube rectifier then there are no real circuit safety/reliability implications in going up by a factor of even X10. More should give a tighter (more HiFi) sound.
If using a tube rectifier you MUST stick to the maximum C1 spec for the rectifier.
Cheers,
Ian
No, its Diode Bridge...and yeah heard you increase quite a bit with that..but with tube going too much stripp's the plates?..
mainly just want to try I'm assuming the usual reservoir/series network/balancingEQing resistors/Fuse then Paralleling networks etc.. but like about 3-4x amount capacitance...mainly because all I have at the moment/ readily available... and yeah many claiming huge difference cleaner/hi-fi/stiffer response.
No not 22uf 450v.. like Mixing 47uf/100uf/330uf stuff etc....I'm worried/kinda scared/uncertain about the 330uf etc haha
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The main concerns with large BULK capacitance are:
1. In-Rush current at cold tart-up....
2. Peak currents during steady state operation...
In-Rush is easily solved....
2. Your diodes flow current based on conduction angle.... conduction angle gets smaller as you increase your BULK capacitors.... As the conduction angle get smaller, the Peak current will increase due to the smaller amount of time to pass all this re-charge current... These Peak currents occur PRIOR to the crest of the voltage waveform, thus grossly distorting the current waveform..this make for some nasty EMI issues with compliance to rules governing polluting the mains voltage...
1. In-Rush current at cold tart-up....
2. Peak currents during steady state operation...
In-Rush is easily solved....
2. Your diodes flow current based on conduction angle.... conduction angle gets smaller as you increase your BULK capacitors.... As the conduction angle get smaller, the Peak current will increase due to the smaller amount of time to pass all this re-charge current... These Peak currents occur PRIOR to the crest of the voltage waveform, thus grossly distorting the current waveform..this make for some nasty EMI issues with compliance to rules governing polluting the mains voltage...
So a Few of these Samxon 450v/330uf are not going to blow up if I try something? haha
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Nevermind...Getting a a Sick sound with some old Samxon LPs..just added 330uf to Resevoir... Wow sounds just huge/focused/clean/clear etc...just a little bump/enough to what I was wanting to hear/response.
You will get to a point where you need a soft start circuit.
I designed and built my own based on a small PIC micro and a triac.
The PIC slowly ramps up the phase angle until teh transformer gets full power.
Works a treat up to 3KW.
I designed and built my own based on a small PIC micro and a triac.
The PIC slowly ramps up the phase angle until teh transformer gets full power.
Works a treat up to 3KW.
330uf won't hurt anything; hell you could even go to a 1000uf. You should notice, that beyond a certain point upping the capacitance, you not going to hear much difference.
Inrush currents are irrelevant, in practice, as you aren't going to be adding farads of capacitance to your amp. The one exception is if your standby switch is between the diodes and filter capacitors; several hundred uf charging up is enough to weld the switch contacts closed, so your standby switch will no longer be able to switch off.
Peak currents don't matter much either as the current consumption in a tube amp is in ma and not amps.
Modern diodes can withstand surge currents many times what their average current rating is. for example, a 1n4007 which is rated for 1 amp of continuous current can withstand 30 amps of inrush current for short periods of time.
Now, one thing that people may not like is the sound of the amp with a very stiff power supply; what several hundred uf of capacitance will do. A lot of the sound that guitarists like is actually amplifier distortion; a stiff power supply tends to lessen the amp's distortion. Now, for a bass amp, the opposite is true; a stiff supply tends to make a bass amp sound better.
It's all a matter of personal taste.
Inrush currents are irrelevant, in practice, as you aren't going to be adding farads of capacitance to your amp. The one exception is if your standby switch is between the diodes and filter capacitors; several hundred uf charging up is enough to weld the switch contacts closed, so your standby switch will no longer be able to switch off.
Peak currents don't matter much either as the current consumption in a tube amp is in ma and not amps.
Modern diodes can withstand surge currents many times what their average current rating is. for example, a 1n4007 which is rated for 1 amp of continuous current can withstand 30 amps of inrush current for short periods of time.
Now, one thing that people may not like is the sound of the amp with a very stiff power supply; what several hundred uf of capacitance will do. A lot of the sound that guitarists like is actually amplifier distortion; a stiff power supply tends to lessen the amp's distortion. Now, for a bass amp, the opposite is true; a stiff supply tends to make a bass amp sound better.
It's all a matter of personal taste.
Yeah, definitely notice quite a bit stiffer/tight/sound/added Resonance/thickness/ jumps out more response, is/sounds/feels a good bit louder/, wasn't really expecting that much of a change etc. I can see how increasingly more, bass players/or wanting that real clean/hi-fi response etc...even upper registers sounds a good bit more smooth/silky like. Run next to no NFB etc haha
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Nah I don't have anything of that capacitance/HV...just had a few things from Junked comp/part PSUs. I just remember reading about this somewhere to try upping capacitance after/initial rec smoothing/RC...same for some that want an underfiltered/loose response etc. As well as possibly eliminating/reducing "ghosting"/fizz/fuzz that rides sound/notes/decay etc.
now later on the chain/supply Parallel networks I don't know assuming same thing response?
Appreciate the Info though...attempting to Research/Learn.
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I don't know if I understand your last question... Are you asking about more capacitance further on down the line, like for the preamp tubes?
Preamp tubes run in Class "A" don't really require that much filtering because their average running current is fairly constant. More filtering will help eliminate noise in the circuit so it would probably open up the sound of the preamp. I doubt it would give you much more clean headroom in the preamp though, but that is a guess on my part.
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