Why with a tube?
Transistors may be better if properly used.
http://amfone.net/Amforum/index.php?topic=4842.0
Transistors may be better if properly used.
http://amfone.net/Amforum/index.php?topic=4842.0
Hi CarlyBoy,
Any old text books from the early 60's and before will cover this topic. The early Radio Amateurs Handbooks should cover this also. Your listed resources should cover this topic quite well also.
Wavebourn, more than one way to skin a cat. CarlyBoy wants to use tubes for this. Notice he asked in the tube forum.
-Chris
Any old text books from the early 60's and before will cover this topic. The early Radio Amateurs Handbooks should cover this also. Your listed resources should cover this topic quite well also.
Wavebourn, more than one way to skin a cat. CarlyBoy wants to use tubes for this. Notice he asked in the tube forum.
-Chris
Bob Pease, a staff scientist for National Semiconductor and a writer for Electronic Design magazine, ran a series of articles on a tube regulated supply and ripple reduction. In the first of the series, attached here, you can see the basic schematic. In the next two articles, he described a novel approach to ripple reduction using feedback to modulate the PS "ground". While this regulator will be too complicated for most audiophiles, it does show how well a tube unit can perform, and might give some design ideas.
anatech said:
Notice I've asked him why the tube, not you. To achieve the same results with tubes as with modern semiconductors a power regulator needs to be much more expensive and radiate more heat. If there are some other reasons to use tubes in regulators, I would like to know them. But I defenitely do not like anymore to read your comments with destructive meaningless critics, Chris. And I assume, nobody likes...
Wavebourn said:
Hi,
While similar, yes even technically better, results may be achieved by using sand that same sand invariably will leave its sonic fingerprint. A fingerprint some us just do not like.
This is why some of us still use vacuum technology in the first place. Call us crazy but not deaf.....
Cheers,
Quote:
Hi,
While similar, yes even technically better, results may be achieved by using sand that same sand invariable will leave its sonic fingerprint. A fingerprint some us just do not like.
This is why some of us still use vacuum technology in the first place. Call us crazy but not deaf.....
Cheers,
Welcome back Frank.
Like Frank said
Plus, I like the cool colors.
Hi,
While similar, yes even technically better, results may be achieved by using sand that same sand invariable will leave its sonic fingerprint. A fingerprint some us just do not like.
This is why some of us still use vacuum technology in the first place. Call us crazy but not deaf.....
Cheers,
Welcome back Frank.
Like Frank said
Plus, I like the cool colors.
Hi,
Howdy, Joe.
Further to my previous post, there are a myriad of reasons why one would prefer to use vacuum tubes for regulation besides sound or other personal preferences.
Among these would rank reliability, ease of replacement in case of a faulty tube, just some examples that spring to mind.
Most of all, it's fun to learn and let's face it, semi-conductors are such boring devices, aren't they?
Cheers,
Howdy, Joe.
Further to my previous post, there are a myriad of reasons why one would prefer to use vacuum tubes for regulation besides sound or other personal preferences.
Among these would rank reliability, ease of replacement in case of a faulty tube, just some examples that spring to mind.
Most of all, it's fun to learn and let's face it, semi-conductors are such boring devices, aren't they?
Cheers,
fdegrove said:Hi,
Most of all, it's fun to learn and let's face it, semi-conductors are such boring devices, aren't they?
Tests differ. Both are when used inproperly.
Why don't we have a forum for lowers of optimal solutions where we may discuss combinations of tube, solid state analog, digital technologies for better results such as clearest signatures, and nobody will kick us?
FWIW, my take on the tube regulator versus solid-state regulator question: If we set aside noise for a moment, all power supplies, regulated or not, will present some amount of output impedance to the supplied audio circuit. Zero ohms is the goal, but reality gives us something else. This impedance will be non-linear, creating distortion, just like any other impedance due to active devices. Furthermore, this impedance will have a resistive part, and a reactive part (a phase angle) which varies across the audio band. As signal current flows through the power supply, it creates a voltage across this impedance. This distorted voltage, hopefully tiny, will then add to the desired signal passing through the amplifier. In this way, the sonic footprint of the regulator is heard in the output. This new signal voltage will carry with it the distortion character of the power supply components that created it. Would you rather listen to a signal voltage created by a regulator triode’s cathode, or by a regulator transistor’s emitter or FET source? If it's going to be audible, I'll pick the tube's character any day.
Having said all that, it is possible to design either a tube or a solid state regulator with an output impedance of far less than 1 ohm across the audio band, so that any signal voltage created will be exceedingly tiny. Not everyone goes to this trouble (see my prior posting's schematic). If they did, there would be less to argue about.
Furthermore, if you place capacitor(s) across the output, which is usual, the cap(s) will usually define the output impedance at higher frequencies.
And, some audio circuits will be more susceptible to residual power supply signal voltages than others. Class A push-pull or balanced topologies will be the least susceptible.
So the selection of power supply regulator is not only a matter of taste, but also a matter of regulator design performance attained, as well as the power supply rejection of the supplied audio circuit. In other words, it depends...
Having said all that, it is possible to design either a tube or a solid state regulator with an output impedance of far less than 1 ohm across the audio band, so that any signal voltage created will be exceedingly tiny. Not everyone goes to this trouble (see my prior posting's schematic). If they did, there would be less to argue about.
Furthermore, if you place capacitor(s) across the output, which is usual, the cap(s) will usually define the output impedance at higher frequencies.
And, some audio circuits will be more susceptible to residual power supply signal voltages than others. Class A push-pull or balanced topologies will be the least susceptible.
So the selection of power supply regulator is not only a matter of taste, but also a matter of regulator design performance attained, as well as the power supply rejection of the supplied audio circuit. In other words, it depends...
Hi All,
CarlyBoy requested more information on tube regulation.
See post #1 ...........
(Threadjacking)
Brian,
Agreed on all your points. Thanks.
-Chris
CarlyBoy requested more information on tube regulation.
See post #1 ...........
Wavebourn, I was not doing anything except pointing this out. If you wish to debate this choice, please start your own thread. You will notice I did not state a preference.
By talking about it here, you are threadjacking. We have a thread for that too.
(Threadjacking)Brian,
Agreed on all your points. Thanks.
-Chris
phn said:
anyway back on topic.
very nice page.
also another article to read would be RDH chapter 33. I think they are available from pete millett's site (not sure of the url but searching for it should be no problem)
not sure if tube regulation is available in the NEETS site but you can check.
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