Dazed and confused about the need to choke before filter in the power supply chain. Does a good choke lower the capacitance necessary to provide a clean dc signal to the rest of a tube amp?
Just starting with some junkbox parts and maybe some purchases if necessary.
Thanks
Tim (The Flatulist)
Just starting with some junkbox parts and maybe some purchases if necessary.
Thanks
Tim (The Flatulist)
Thanks for the the replies! Funny how the answer always make sense once revealed. I understand the fundamentals of both but didn't think it through before posting. "Hanging head in shame" Appreciate the info links!
I had exactly the same question in the 90s. All the chokes i had at hand sounded really horrible and given a choice i would rather have had microfarads than Henries. This all changed as soon as i tried Lundahl chokes. Eventually progressed beyond Lundahl to amorhous and today would not consider a PS without chokes.
Choke input for me is unavoidable due to the mercury rectifiers, but this preference is not universal - some people seem to prefer the sound of cap input supplies.
Hello,
Eventually progressed beyond Lundahl to amorhous and today would not consider a PS without chokes
I also think Lundahl chokes are very nice . A big reason for me that they have lots of choice because they offer several models that can be bought with different airgaps. And now you can even ask for a different airgap with a certain model. They have like a stock of coils and during assembly they will adjust the airgap as you desire.
I have read that amorphous cores are easier to saturate. So some could taker less AC.
What is the sonical character that makes you switch to them?
In a LCLC supply with one amorphous choke which one gives the most benefits , the input choke or the other one? I find generally that the influence of the input choke is bigger.
Greetings, eduard
p.s in the attachment the old and the new input choke in my DDDAC. Just going up in Henry and weight
Eventually progressed beyond Lundahl to amorhous and today would not consider a PS without chokes
I also think Lundahl chokes are very nice . A big reason for me that they have lots of choice because they offer several models that can be bought with different airgaps. And now you can even ask for a different airgap with a certain model. They have like a stock of coils and during assembly they will adjust the airgap as you desire.
I have read that amorphous cores are easier to saturate. So some could taker less AC.
What is the sonical character that makes you switch to them?
In a LCLC supply with one amorphous choke which one gives the most benefits , the input choke or the other one? I find generally that the influence of the input choke is bigger.
Greetings, eduard
p.s in the attachment the old and the new input choke in my DDDAC. Just going up in Henry and weight
Attachments
You are asking some pertinent questions. Cost me dearly to get these answers 🙂
I cannot really recommend the Lundahl amorphous chokes. They give you just a glimpse into what is possible but at the expense of bass and an oddly squashed sounding midrange. And yes, they are too small for using as input chokes. I was unfortunate to buy them before this admission appeared into the datasheet.
What i use is an input wound on AMCC400 followed by a differentially connected Lundahl in the second stage. Best of both worlds to my ears.
A choke stores and releases energy, smoothing the bumpy waveform emitted by the rectifier.
Thats it. Its not majic and holds no musical qualities in and of itself.
Your device, regardless of what it is, wants a constant supply of electrons (current) under a smooth, unvarying pressure (voltage). BITD, when capacitors were expensive and magnetics were cheap a choke input make sense. These days, this task is often best achieved with large capacitors and a regulator, usually of the cursed and evil sand-assisted variety.
Some will tell you this sand makes music sound grainy, abrasive, etc. I beg to differ.
I use Salas shunts in all my preamps/phono stages. The chokes in the filter are still mandatory despite your disbelief in their musical qualities 🙂
This is obviously according to my taste and perception. No doubt someone else will totally love the stark, grey, flat portrayal depicted by semi rectication and series regs 😀
Hello, My DDDAC uses Tent shunt regulations incorporated in the circuit boards fed by a high current ( 1A) choke input. My phono preamp uses a tube shunt regulation '' guided '' by an OB2 voltage reference tube. BOTH circuit fed by a seperate choke input supply with 6x4 tube rectifier. The same idea used in my tube line amp. My single ended mono block uses Allen Wright solid state with choke input supply with 5R4GYB. The reference voltage of the shunt ( 15 volt) is supplied by a choke input supply too. One could think that because of the shunt there is no choke input necessary. BUT Allen wright told me to use it. Changing the input choke to another brand or value was always clearly noticed even with an LCLC supply.
Greetings, Eduard
Eduard
Thank you for the detailed description. We are very much in agreement with the exception of the OB2. I have never been able to achieve bass to my liking from any of the gas filled zeners. Either with resistors or using proper CCS. I think the reason may be the non-negotiable absence of a substantial bypassing cap after the regulator. And it is not just the bass, the entire presentation is too polite for my liking.
Thank you for the detailed description. We are very much in agreement with the exception of the OB2. I have never been able to achieve bass to my liking from any of the gas filled zeners. Either with resistors or using proper CCS. I think the reason may be the non-negotiable absence of a substantial bypassing cap after the regulator. And it is not just the bass, the entire presentation is too polite for my liking.
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