yep at last an R-clc for the conduction angle ,better use the Mark quasimodo to dump the trasformer/diode too ,but yes use only LC filter
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No deny in this.
However at some point, some audio enthusiast start to be aggressive towards suggesting their experience and opportunities to others. I used the word "religion" for this.
While I respect everyone's path of audio experience, labeling different methods with heavy sounding epithets like "dirty parts" is inherently discouraging to some enthusiasts following another kind of audio paths.
My final point is - there are different ways to achieve an excellent sound for your own ears and in conclusion there are no "dirty vs blessed" ways to do it.
Es geht sehr gut, vielen Dank.
My ideal is always good, massive iron. No Zotl, NO OTL.
Just good, expensive and rare iron. The more, the better. Thats an audible pound, which pays off well.
And as I'm no genius audio designer, just trying to avoid mistakes is a big achievement.
A fully functional design, massively overdimensioned sounds most often great and avoids much calculation.
Sometime, pics show more than words.
My ideal is always good, massive iron. No Zotl, NO OTL.
Just good, expensive and rare iron. The more, the better. Thats an audible pound, which pays off well.
And as I'm no genius audio designer, just trying to avoid mistakes is a big achievement.
A fully functional design, massively overdimensioned sounds most often great and avoids much calculation.
Sometime, pics show more than words.
Attachments
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Totally agree with that statement.
The description as "dirty parts" should be restricted to Callahan's magnun colt.😀
Attachments
"just trying to avoid mistakes."
How is that an achievement? It is just plain playing it save. No progress at all.
We know now that the earth is round (not everyone i suppose) because people have traveled it, risking their lives and not stayed safely at home.
BTW, for who is interested, more info of the Zotl technology can be found here:
US5612646A - Output transformerless amplifier impedance matching apparatus
- Google Patents
ZOTL and ferrites
How is that an achievement? It is just plain playing it save. No progress at all.
We know now that the earth is round (not everyone i suppose) because people have traveled it, risking their lives and not stayed safely at home.
BTW, for who is interested, more info of the Zotl technology can be found here:
US5612646A - Output transformerless amplifier impedance matching apparatus
- Google Patents
ZOTL and ferrites
What chokes are you all using when implementing a choke input filter? I have attempted a choke input several times and tried a variety of chokes, some modern and many vintage, but have not kept a choke in the first position in the final design. I have a purpose built listening room that is very, very quiet, and choke inputs have always created mechanical buzzing in the choke mostly, but less often in both choke and transformer. This buzzing noticeably increases the noise floor and, more importantly, annoys me. Any suggestions for chokes that will be silent in the input position would be much appreciated,
How do you calculate the appropriate size of the resistor at the input to reduce the conduction angle?
Have you tried a small capacitor before the choke, like 1uF, 2.2uF? Does that help?
Yes, thats the complete difference to "we invent the tube amp for a second time".
So what does it mean, to just avoid doing mistakes?
Could you make a meal like a five star chef de cuisine is able to?
Do you think it means to invent the whole kitchen cooking once again, to make a better meal?
That is absolute nonsense.
To cook an excellent meal means first to buy the best parts, means the best and the freshest ingredients. And then to cook it in the perfect way. Thats just enough. So if its that easy, why can't every amateur cook don't do it?
Why you have to book, visit and eat at a five star restaurant to once in your life taste a perfect steak or some other perfect diner?
Because it s the exact opposite to easy. Its hard work. Its years of experience. Its years of perfectioning, its years of striving for perfection in details.
With your intention, nothing is being won.
It just means invention has priority, all old and established is out of fashion.
Lets look here, my amp is the newest fashion, the latest invention, the most amazing circuit of all. Could be an ego number, too.
To choose the right parts, put them in the right place and to dimension everything the right way may sound trivial, but it isn't. Just the other way around: if that would be trivial, why the majority still don't manage to do it perfect that way?
Mediocrity is the measure of things. With invention, perfection doesn't come automatically. From invention to perfection is the real hard way. Every company can tell you. Invention without striving for perfection means still mediocrity. When I look at your designs and their implementation, it looks like something I did 30 years ago.
Far, far away from any perfection. Just like an amateur cook trying to do a steak at his homebrew kitchen.
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You need a well documented choke. Lundahl does it well. When designing custom chokes for customers, I usually ask a lot of questions and many clients aren't even aware of their importance when choosing a choke.
You can't just throw a random choke in your power supply chain.
The most important parameter for a LC duty choke is AC flux density headroom. There, you have a pulsating DC with 100 or 120Hz frequency, approximately 0.5 times the secondary transformer's voltage.
If your choke isn't designed with headroom in mind, such as a Pi filter choke, where the flux density is used for mostly DC current, it can saturate, then make noise.
Despite of that, you can use a Pi filter choke for LC input if you are aware of its construction first, and calculate how the flux densities get distributed. Usually if you cannot disassemble the choke and increase the air gap, the simplest thing to do is to underestimate the choke and use it much bellow its maximum Idc, which will give you swinging flux density headroom.
It's not a rocket science topic, but you should not underestimate some important choke parameters.
P.S. I favour LC filters too. And from experience, the closer I get to the source, the higher the audibility. Ironically, the most audible power supplies are where my digital stuff is - playback computer and digital section of DAC. Despite all the switching stuff a PC has on its motherboard, one of my greatest upgrades was modifying the linear PC supply with an LC filter.
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I would say that "choke input filter " is the proper name for the LC filter I mentioned previously. You can`t use just any old choke as a choke input filter.
No, a well functioning LC filter puts less stress on the power supply transformer.
Rectifying noise will not be reflected back into the power supply transformer but (and that is one of the advantages of LC filtering) will be sucked up by the choke.
Rectifying noise will not be reflected back into the power supply transformer but (and that is one of the advantages of LC filtering) will be sucked up by the choke.
The choke input filter puts stress on the diode and the transformer.
The choke input filter is a non-dirty part.
The choke input filter is a non-dirty part.
[/QUOTE]Interesting, I've found quite the reverse, but everyone is different in how they view these things.
Explanation: the choke input filter renders the diode and the transformer into a nearly continuous conduction (rather than saltatory conduction), reducing transformer output voltage, efficiency and distortion, therefore the choke input filter is classified as a non-dirty part.
No, high current pulses put much greater stress on the transformer secondary than continuous conduction. The choke needs to have sufficient inductance to ensure continuous conduction. Check ANY textbook.
True, but there are more ways to go about getting a clean B+. if you add series resistance before the bridge rectifier SS diodes and put a 100uH in series with a normal CRC this will filter most of the high frequency junk you get with slow diodes.
I dislike choke supplies simply because they need a relatively constant current draw to get the regulation, then there is the weight, expense and the fact that a poorly implemented choke supply will ring like crazy. and cause all kind of weird reactance effects with the output transformer.
CRC with silicon diodes is easier to get right. Drop in a tube regulator and knock the noise down to under 1mV. Then put a pot in series with the feedback loop and trim the frequency response of your regulator to your liking.
PEH536 series industrial electrolytics are my go to. If i want them to act like an old capacitor i just put 22uH in series with them. Problemsolved. Much better lifetime as well.
I did some experiments with choke supplies back in the day, for this i built a mosfet constant current source that would load the choke supply with 50 to 100mA steps fed in a square wave and modulated the current draw. I had to say: No more chokes for me thank you very much very poor regulation. Even a class A amplifier will have all kind of weird stuff happening once you put in an inductor.
I have a friend, who shall remain nameless as he is quite a private person. After trying some of my regulators, he has not built a tube amplifier without them ever since.
I have used the same regulator for all kinds of projects: PP SE you name it, i even made a lower noise version for a RIAA. Ive posted on the forum about that, and 0% interest.
Inductors are good if you want SMPS or an output transformer, where you sadly cannot get around inductors. They are far less predictable than resistors and active circuits. A choke is just a waste of money, better get a transformer with 100 more VA to compensate for the higher resistive losses in the transformer. Or get one with a shield between primary and secondary to keep out the junk from the mains.
Just my 2C opinion on the matter.
I dislike choke supplies simply because they need a relatively constant current draw to get the regulation, then there is the weight, expense and the fact that a poorly implemented choke supply will ring like crazy. and cause all kind of weird reactance effects with the output transformer.
CRC with silicon diodes is easier to get right. Drop in a tube regulator and knock the noise down to under 1mV. Then put a pot in series with the feedback loop and trim the frequency response of your regulator to your liking.
PEH536 series industrial electrolytics are my go to. If i want them to act like an old capacitor i just put 22uH in series with them. Problemsolved. Much better lifetime as well.
I did some experiments with choke supplies back in the day, for this i built a mosfet constant current source that would load the choke supply with 50 to 100mA steps fed in a square wave and modulated the current draw. I had to say: No more chokes for me thank you very much very poor regulation. Even a class A amplifier will have all kind of weird stuff happening once you put in an inductor.
I have a friend, who shall remain nameless as he is quite a private person. After trying some of my regulators, he has not built a tube amplifier without them ever since.
I have used the same regulator for all kinds of projects: PP SE you name it, i even made a lower noise version for a RIAA. Ive posted on the forum about that, and 0% interest.
Inductors are good if you want SMPS or an output transformer, where you sadly cannot get around inductors. They are far less predictable than resistors and active circuits. A choke is just a waste of money, better get a transformer with 100 more VA to compensate for the higher resistive losses in the transformer. Or get one with a shield between primary and secondary to keep out the junk from the mains.
Just my 2C opinion on the matter.
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Well, the second "no"...
Actually, N101N's reasoning means that the power supply transformer will be relieved 😀
They need a minimal current draw.
When a poorly implemented choke supply rings, I'd say do a better job 🙄
A well implemented choke supply works well.
Not my 2 cents but IME 😀