Hi,
First, I am quite familiar with Bill Whitlock's work and fond of citing it myself, for advantages for transformers in some circumstances.
The likelyhood of any well designed home hifi gear with short cables exhibiting what Bill so charmingly calls a "pin 1 problem" is remote. So promoting the selection of transformer in a preamplifier for domestic use because of it is hardly engineering driven reasoning, it is mythology or simply a desire to be "hip" with all the others that use transformers somewhere.
As for the rest, it is trivial to provide a solid state circuit that outperforms your tube follower in all objective parameters at much lower cost. So, where is the engineering driven reasoning here.
Mind you Sy, I have no problems with you using Tubes or Transformers or challenge you on their use, on the contrary I applaud your choices. I also have no issue with your use of solid state constant current sources (I do have with LED's in cathodes of amplifying tubes though - reasons that are very much classically engineering driven in addition to reasons of "good sound"), in fact I use them with quite some regularity in my designs as well.
But my agreement with your choices is not for reasons that are engineering driven in the sense you elect to interpret it (on the contrary), but simply because I know the results will subjectively sound better, the inferior performance compared to "engineering driven" circuits in classic measurements non-withstanding.
And using whatever it takes (Chokes, CCS, Mosfets, IC's, Tubes, whatever else) to get "good sound" is what I PERSONALLY consider Engineering Driven design.
Sad you had to paint yourself so much into a corner that you cannot simply say: "I use Tubes and Transformers because I like to!", the funny thing is that I CAN say that and I can say "I use Mosfets and CCS because I like to" at the same time.
I hope the paint eventually dries out... 🙂
Ciao T
Try reading the article (including the "high" distortion) and the excellent work of Bill Whitlock. Res ipsa and all that.
First, I am quite familiar with Bill Whitlock's work and fond of citing it myself, for advantages for transformers in some circumstances.
The likelyhood of any well designed home hifi gear with short cables exhibiting what Bill so charmingly calls a "pin 1 problem" is remote. So promoting the selection of transformer in a preamplifier for domestic use because of it is hardly engineering driven reasoning, it is mythology or simply a desire to be "hip" with all the others that use transformers somewhere.
As for the rest, it is trivial to provide a solid state circuit that outperforms your tube follower in all objective parameters at much lower cost. So, where is the engineering driven reasoning here.
Mind you Sy, I have no problems with you using Tubes or Transformers or challenge you on their use, on the contrary I applaud your choices. I also have no issue with your use of solid state constant current sources (I do have with LED's in cathodes of amplifying tubes though - reasons that are very much classically engineering driven in addition to reasons of "good sound"), in fact I use them with quite some regularity in my designs as well.
But my agreement with your choices is not for reasons that are engineering driven in the sense you elect to interpret it (on the contrary), but simply because I know the results will subjectively sound better, the inferior performance compared to "engineering driven" circuits in classic measurements non-withstanding.
And using whatever it takes (Chokes, CCS, Mosfets, IC's, Tubes, whatever else) to get "good sound" is what I PERSONALLY consider Engineering Driven design.
Sad you had to paint yourself so much into a corner that you cannot simply say: "I use Tubes and Transformers because I like to!", the funny thing is that I CAN say that and I can say "I use Mosfets and CCS because I like to" at the same time.
I hope the paint eventually dries out... 🙂
Ciao T
PS, I am still waiting for you revealing your low distortion loudspeakers and your engineering reasons for transformers and tubes...
The former can be found on my website; they are a good example of system design. Like the rest of my system, they are nonstandard and must be used in conjunction with some very specific components. I have almost no "plug'n'play" that can be dropped into more conventionally engineered systems.
Please note the preamp measurements which show some very interesting advantages beyond the limited "pin 1 problem" that you've focused on, not to mention linearity far better than one needs in order to render such a stage inaudible.
You may enjoy my any-minute-now-to-appear article on tube phono amp design, where I outline yet more engineering reasons to use tubes in some applications and why non-standard interfaces and levels may be the most appropriate choices. Then again, you may not.
Hi SY,
I'm looking forward to seeing your phono pre-amplifier article. Is it going to be published in the article section here or in AudioXpress?
I still need to order some infra-red LEDs per our last phono stage discussion. I am still using those diodes - I'll admit they work a lot better than the RC cathode bias network they replaced. Rather funny actually as we had a very direct A/B at the last QAF... Even a couple of very linear Blackgate standard el caps paralleled didn't sound right in this application.
When next in Boston?
Kevin
I'm looking forward to seeing your phono pre-amplifier article. Is it going to be published in the article section here or in AudioXpress?
I still need to order some infra-red LEDs per our last phono stage discussion. I am still using those diodes - I'll admit they work a lot better than the RC cathode bias network they replaced. Rather funny actually as we had a very direct A/B at the last QAF... Even a couple of very linear Blackgate standard el caps paralleled didn't sound right in this application.
When next in Boston?
Kevin
Kevin, it will be here.
Actually, I was just in Boston, but it was a quick in-and-out (though I did manage to see Scott). Working on getting a return trip there, and if so, I know a wonderful little Chinese joint...😀
Actually, I was just in Boston, but it was a quick in-and-out (though I did manage to see Scott). Working on getting a return trip there, and if so, I know a wonderful little Chinese joint...😀
Kevin, it will be here.
Actually, I was just in Boston, but it was a quick in-and-out (though I did manage to see Scott). Working on getting a return trip there, and if so, I know a wonderful little Chinese joint...😀
Me too.. 😀 Let me know if you succeed..
Looking forward to seeing the article.
Hi Sy,
You mean you make unsupported claims that the NHT M3.3 offers low distortion? Like in about as much distortion as an OPA604 Audio Op-Amp, which I think most will agree is low distortion?
Do you have actually some solid material to back up that the NHT M3.3 does not have about as much distortion as any other dynamic loudspeaker? Because other dynamic speakers surely must be classed as "high distortion", at least when compared to most electronics.
Which is of little consequence, TBH, as you claim "engineering driven reasoning" yet you still persist using Tubes, whose use in Audio cannot be justified by any engineering driven reasoning, as ANY tube ciruit can be outperformed in terms of distortion, noise, dynamic range, cost, size, weight, power consumption and any other particular objective parameter you care to name by a few cent to at best a few dollars worth of integrated circuits.
Your Preamp show 0.005% IMD at 2V with unspecified load.
By comparison a OPA134 shows <<0.001% IMD at 2V into a 2K load.
To excuse the choice of tubes in this case with "but the distortion is low enough" is also not a valid engineering reason. 🙂
That is unless we accept the argument "Tubes sound better" as a sensible engineering reason (which opens the door to other "XXX sounds better" reasons).
You make no such argument in your writing.
So, we find you using tubes with no particular reason we can describe as engineering driven. You do not use them because they sound better or because they perform better in any other area.
This leaves only fashion and coolness factor, unless you have given a reason that escaped me in reading?
As for the noise reduced by interposing the Preamp into the external loop of a Creative Audigy computer sound card, it could also be solved by correct design.
May I actually commend Douglas Self's writing on groundloops etc. for reading?
Ground Loops
Balanced Line Technology
Good design techniques can produce results at least as good as inserying a transformer, at much lower cost, size, weight.
Me?
I just like to use Transformers and Tubes where I use them because they sound better. So I am okay using them, as I recognise @good sound@ as valid engineering goal.
Unless you do too you have no excuse for using transformers and tubes.
Looking forward to it. I do find your stuff quite interesting. I will make sure afterwards to comment where using chokes instead of resistors will improve the design... 🙂
Ciao T
The former can be found on my website;
You mean you make unsupported claims that the NHT M3.3 offers low distortion? Like in about as much distortion as an OPA604 Audio Op-Amp, which I think most will agree is low distortion?
Do you have actually some solid material to back up that the NHT M3.3 does not have about as much distortion as any other dynamic loudspeaker? Because other dynamic speakers surely must be classed as "high distortion", at least when compared to most electronics.
they are a good example of system design.
Which is of little consequence, TBH, as you claim "engineering driven reasoning" yet you still persist using Tubes, whose use in Audio cannot be justified by any engineering driven reasoning, as ANY tube ciruit can be outperformed in terms of distortion, noise, dynamic range, cost, size, weight, power consumption and any other particular objective parameter you care to name by a few cent to at best a few dollars worth of integrated circuits.
Please note the preamp measurements which show some very interesting advantages beyond the limited "pin 1 problem" that you've focused on, not to mention linearity far better than one needs in order to render such a stage inaudible.
Your Preamp show 0.005% IMD at 2V with unspecified load.
By comparison a OPA134 shows <<0.001% IMD at 2V into a 2K load.
To excuse the choice of tubes in this case with "but the distortion is low enough" is also not a valid engineering reason. 🙂
That is unless we accept the argument "Tubes sound better" as a sensible engineering reason (which opens the door to other "XXX sounds better" reasons).
You make no such argument in your writing.
So, we find you using tubes with no particular reason we can describe as engineering driven. You do not use them because they sound better or because they perform better in any other area.
This leaves only fashion and coolness factor, unless you have given a reason that escaped me in reading?
As for the noise reduced by interposing the Preamp into the external loop of a Creative Audigy computer sound card, it could also be solved by correct design.
May I actually commend Douglas Self's writing on groundloops etc. for reading?
Ground Loops
Balanced Line Technology
Good design techniques can produce results at least as good as inserying a transformer, at much lower cost, size, weight.
Me?
I just like to use Transformers and Tubes where I use them because they sound better. So I am okay using them, as I recognise @good sound@ as valid engineering goal.
Unless you do too you have no excuse for using transformers and tubes.
You may enjoy my any-minute-now-to-appear article on tube phono amp design, where I outline yet more engineering reasons to use tubes in some applications and why non-standard interfaces and levels may be the most appropriate choices. Then again, you may not.
Looking forward to it. I do find your stuff quite interesting. I will make sure afterwards to comment where using chokes instead of resistors will improve the design... 🙂
Ciao T
Your Preamp show 0.005% IMD at 2V with unspecified load.
10k, 150pF. If you're claiming that this is not more than sufficiently low to be audibly transparent, please provide evidence.
You mean you make unsupported claims that the NHT M3.3 offers low distortion? Like in about as much distortion as an OPA604 Audio Op-Amp
I was unable to get 100dB SPL in my room out of an OPA604, so your comparison mystifies me.
edit: Checking my lab notebook, actual capacitive load turns out to be more like 250pF
Hi Sy,
I claim nothing on audibility. I merely note that this performance is markedly worse (and using a 2K load would have made even more worse) than that of quite generic operational amplifiers, which cost much individually and in implementation than a tube.
If you criticise the use of a grid choke as performing "worse than a 5 cent resistor", how can you suggest anyone use a 10 USD tube that performs "almost as well (actually 5 - 10 times worse!) as a" 1 USD Op-Amp?
Plus the Op-Amp could do without servo, offer even less input capacitance than your cathode follower and does not require the heater supply and the high tension supply plus around three extra watts in power consumption your selection of a tube imposes.
I am sorry, but you cannot pawn off the selection of the tube as "engineering driven", just like no way.
My point is that ALL Speakers are actually high distortion devices, including yours and mine.
When you suggested the combination "low distortion amplifier" and "low distortion speaker" as means to attain low overall distortion you suggested that a speaker with equally low distortion as the amplifier should be selected.
While in principle a sensible proposition, it presupposes the existence of this "low distortion speaker" (e.g. one with 0.005% IMD to match your linestage). In fact in reality I have yet to encounter such a speaker.
As you suggest to use such speaker, would you kindly provide conrete examples of speakers with a THD of less than 0.3% from 20Hz-20KHz at rated input power (which is something that most people would agree is the performance at which we may describe an amplifier as "low distortion"), so we can match it with the low distortion amplifier and see how the end result sounds?
If you cannot suggest such a speaker, may I suggest that the approach of cancelling some of the speaker distortion with the Amplifier's pre-distortion has merit? A similar system was used quite sucessfully with vinyl LP's since the late 60's.
SY, allow me to be blunt.
You cannot sit between two chairs, unless you enjoy the floor. I would like to make the whole thing a wide sofa, with space for many ways, not juts two narrow polarised "chairs", how about you?
You cannot defend your own choices that are less than solidly based in "best engineering practice" as engineering driven while attempting to put down such choices by others as not being engineering driven.
If a 5 cent resistor is the engineering driven choice over a grid choke, then a 100 cent op-amp is the engineering driven choice over a tube, plain and simple.
We can safe ourself the remainder of the argument, I believe my point has made very clearly and illustrated by challenging your unsupported assertion.
Now, shall we continue to disagree and pursue our own respective design approaches, while respecting that other approaches do have validity?
In the end everyone will be richer in the result, with a wider spectrum from design methods to select from and a wider range of engineering choices to attain the goal, which remains good sounding music.
Ciao T
10k, 150pF. If you're claiming that this is not more than sufficiently low to be audibly transparent, please provide evidence.
I claim nothing on audibility. I merely note that this performance is markedly worse (and using a 2K load would have made even more worse) than that of quite generic operational amplifiers, which cost much individually and in implementation than a tube.
If you criticise the use of a grid choke as performing "worse than a 5 cent resistor", how can you suggest anyone use a 10 USD tube that performs "almost as well (actually 5 - 10 times worse!) as a" 1 USD Op-Amp?
Plus the Op-Amp could do without servo, offer even less input capacitance than your cathode follower and does not require the heater supply and the high tension supply plus around three extra watts in power consumption your selection of a tube imposes.
I am sorry, but you cannot pawn off the selection of the tube as "engineering driven", just like no way.
I was unable to get 100dB SPL in my room out of an OPA604, so your comparison mystifies me.
My point is that ALL Speakers are actually high distortion devices, including yours and mine.
When you suggested the combination "low distortion amplifier" and "low distortion speaker" as means to attain low overall distortion you suggested that a speaker with equally low distortion as the amplifier should be selected.
While in principle a sensible proposition, it presupposes the existence of this "low distortion speaker" (e.g. one with 0.005% IMD to match your linestage). In fact in reality I have yet to encounter such a speaker.
As you suggest to use such speaker, would you kindly provide conrete examples of speakers with a THD of less than 0.3% from 20Hz-20KHz at rated input power (which is something that most people would agree is the performance at which we may describe an amplifier as "low distortion"), so we can match it with the low distortion amplifier and see how the end result sounds?
If you cannot suggest such a speaker, may I suggest that the approach of cancelling some of the speaker distortion with the Amplifier's pre-distortion has merit? A similar system was used quite sucessfully with vinyl LP's since the late 60's.
SY, allow me to be blunt.
You cannot sit between two chairs, unless you enjoy the floor. I would like to make the whole thing a wide sofa, with space for many ways, not juts two narrow polarised "chairs", how about you?
You cannot defend your own choices that are less than solidly based in "best engineering practice" as engineering driven while attempting to put down such choices by others as not being engineering driven.
If a 5 cent resistor is the engineering driven choice over a grid choke, then a 100 cent op-amp is the engineering driven choice over a tube, plain and simple.
We can safe ourself the remainder of the argument, I believe my point has made very clearly and illustrated by challenging your unsupported assertion.
Now, shall we continue to disagree and pursue our own respective design approaches, while respecting that other approaches do have validity?
In the end everyone will be richer in the result, with a wider spectrum from design methods to select from and a wider range of engineering choices to attain the goal, which remains good sounding music.
Ciao T
I am sorry, but you cannot pawn off the selection of the tube as "engineering driven", just like no way.
If you're allowed to decide the engineering criteria post hoc, I'd agree. But I didn't design it to your particular criteria. If you would like me to do so, I am available for an astonishing unreasonable hourly rate.
When you suggested the combination "low distortion amplifier" and "low distortion speaker" as means to attain low overall distortion you suggested that a speaker with equally low distortion as the amplifier should be selected.
When you start a long chain of reasoning with a false assumption, the rest of the argument must be discarded.
Hi Sy,
Thank you for your kind offer.
I suspect I may just about mange myself, if with difficulty... 😉
As for the rest, I consider the matter closed and the untennability of your position adequatly illustrated, from a viewpoint of, aehhhhm, engineering driven reasoning.
Ciao T
If you would like me to do so, I am available for an astonishing unreasonable hourly rate.
Thank you for your kind offer.
I suspect I may just about mange myself, if with difficulty... 😉
As for the rest, I consider the matter closed and the untennability of your position adequatly illustrated, from a viewpoint of, aehhhhm, engineering driven reasoning.
Ciao T
As for the rest, I consider the matter closed and the untennability of your position adequatly illustrated, from a viewpoint of, aehhhhm, engineering driven reasoning.
I'm frankly disappointed that you haven't corrected your false assumptions, then try to recast the argument appropriately.
Hi Sy,
I have finally the time to come back to this thread.
In addition to this you made elsewhere comments along the lines of:
"Extraordinary claims require extraordinary proof!"?
Do you agree that I am representing your position right? I would not want to misrepresent your position!
If so, secondly, strictly based on your understanding of basic Electronics (I'd say about EE101 Level is all that is needed), are any of the objective statements I made in my original post (see link) NOT covered by such basic electronics?
I appreciate that statements of the kind "sounds like this or that" do not fall under the above, I think it was clear from the context that they where attempting to describe the subjective impact of the objectively observable effects. In the end most of us here ant to know "what it sounds like", not what Mr. A. P. Two has to say on the subject.
To make it easier for you to answer point by point I am listing my assertion's again, a little more summarised. Note that all these assertion's apply to "generic" SE Amplifiers (self bias output, lowish impedance driver stage) though they can be obviously extended to other topologies:
1) Grid Chokes CAN in many cases be used to provide a higher grid circuit Impedance in the audio range than allowed by the grid circuit DCR limit specification of the DHT output Tube while producing a DCR well below that of the Datasheet Limit. Insofar they can be "better" than a 5 cent resistor.
2) If the amplifiers driver stage offers a low drive impedance (say <<5K) and enough current capability to drive the grid positive on peaks; using a correctly implemented gridchoke instead of a resistor produces a greater amount of output power for a given amount of distortion. Insofar they can be "better" than a 5 cent resistor.
3) In addition to 2) using a gridchoke instead of resistor in the case described in 2) will also produce improved (reduced time) recovery from repeated short overload conditions and provide greater amounts of peak power for a given distortion limit.
4) That the main mechanism for 2) & 3) is the result from the circuit with gridchoke actually "driving" the grid's average DC level positive as a result of overload conditions keeping the quiescent current in the output tube substantially stable, with respect to quiescent conditions, whereas a circuit with gridresistor produces a more negative average DC level for the grid and thus temporary reduces the quiescent current in the output tube as result of the overload condition.
Do you REALLY insist that any of the above is not covered by ordinary electrical and electronic theory and hence should be considered to constitute an "extraordinary" claim?
Ciao T
I have finally the time to come back to this thread.
Au contraire, he was guided toward a rational decision rather than one guided by unsupported assertions and ex cathedra pronouncements by those with something to sell or promote, as well as a rational reason why plate chokes were useful in limited situations, but not in most others.
In addition to this you made elsewhere comments along the lines of:
"Extraordinary claims require extraordinary proof!"?
Do you agree that I am representing your position right? I would not want to misrepresent your position!
If so, secondly, strictly based on your understanding of basic Electronics (I'd say about EE101 Level is all that is needed), are any of the objective statements I made in my original post (see link) NOT covered by such basic electronics?
I appreciate that statements of the kind "sounds like this or that" do not fall under the above, I think it was clear from the context that they where attempting to describe the subjective impact of the objectively observable effects. In the end most of us here ant to know "what it sounds like", not what Mr. A. P. Two has to say on the subject.
To make it easier for you to answer point by point I am listing my assertion's again, a little more summarised. Note that all these assertion's apply to "generic" SE Amplifiers (self bias output, lowish impedance driver stage) though they can be obviously extended to other topologies:
1) Grid Chokes CAN in many cases be used to provide a higher grid circuit Impedance in the audio range than allowed by the grid circuit DCR limit specification of the DHT output Tube while producing a DCR well below that of the Datasheet Limit. Insofar they can be "better" than a 5 cent resistor.
2) If the amplifiers driver stage offers a low drive impedance (say <<5K) and enough current capability to drive the grid positive on peaks; using a correctly implemented gridchoke instead of a resistor produces a greater amount of output power for a given amount of distortion. Insofar they can be "better" than a 5 cent resistor.
3) In addition to 2) using a gridchoke instead of resistor in the case described in 2) will also produce improved (reduced time) recovery from repeated short overload conditions and provide greater amounts of peak power for a given distortion limit.
4) That the main mechanism for 2) & 3) is the result from the circuit with gridchoke actually "driving" the grid's average DC level positive as a result of overload conditions keeping the quiescent current in the output tube substantially stable, with respect to quiescent conditions, whereas a circuit with gridresistor produces a more negative average DC level for the grid and thus temporary reduces the quiescent current in the output tube as result of the overload condition.
Do you REALLY insist that any of the above is not covered by ordinary electrical and electronic theory and hence should be considered to constitute an "extraordinary" claim?
Ciao T
1) Rarely, and only with tubes showing pathological grid leakage.
2) Generally not significantly.
3) No. A time constant is a time constant.
4) Start with a faulty premise, get faulty conclusions.
And you left out 5:
5) Much bigger, bulkier, expensive, more prone to noise pickup, and with much larger stray impedances and non-ideality.
That one I'd agree with.
2) Generally not significantly.
3) No. A time constant is a time constant.
4) Start with a faulty premise, get faulty conclusions.
And you left out 5:
5) Much bigger, bulkier, expensive, more prone to noise pickup, and with much larger stray impedances and non-ideality.
That one I'd agree with.
Hi,
Well, in this case "Rarely, and only with tubes showing pathological grid leakage" includes 300B and 2A3 in fixed bias mode.
Define "significant". How much more is significant? Is it 10%, 30%, 100%, 1000%?
Yes. And the time constant remains unchanges if I replace a resistor with a choke? Really?
Let me be ABSOLUTELY CLEAR here.
You are saying that with such conditions as I have described, namely overload with the driver stage driving the output tube into gridcurrent, the Grid of the output tube does not become more negative than at quiescent conditions when RC coupling is used and that the grid does not become more positive when LC coupling is used.
And that is to the BEST of your knowledge in electronics?
Yes? Am I representing your position correctly?
Ciao T
1) Rarely, and only with tubes showing pathological grid leakage.
Well, in this case "Rarely, and only with tubes showing pathological grid leakage" includes 300B and 2A3 in fixed bias mode.
2) Generally not significantly.
Define "significant". How much more is significant? Is it 10%, 30%, 100%, 1000%?
3) No. A time constant is a time constant.
Yes. And the time constant remains unchanges if I replace a resistor with a choke? Really?
4) Start with a faulty premise, get faulty conclusions.
Let me be ABSOLUTELY CLEAR here.
You are saying that with such conditions as I have described, namely overload with the driver stage driving the output tube into gridcurrent, the Grid of the output tube does not become more negative than at quiescent conditions when RC coupling is used and that the grid does not become more positive when LC coupling is used.
And that is to the BEST of your knowledge in electronics?
Yes? Am I representing your position correctly?
Ciao T
2A3 isn't nearly as bad as your first choice- 500k grid resistance in the normal cathode bias mode. 250k for the 300B. The numbers are lower for fixed bias, and that's yet one more reason that these tubes are overpriced dinosaurs rather than actual high performers. Were I to feel nostalgic and use them for fashion purposes, I would either use cathode bias or (for best performance) direct coupling via a CF or source follower. I strongly suspect that the grid current would be a worse problem with inductors. And of course, these tubes are generally not used as drivers (the original question), so again, you're dealing with pathology or missing the point or both.
If you have a constant f3 between resistor and choke, the time constant by definition is the same. The slope is different (2nd versus first order), and indeed the inductor will generally show poorer transient response during recovery. That coloration may be one reason why some subjectively prefer the high priced spread.
If you have a constant f3 between resistor and choke, the time constant by definition is the same. The slope is different (2nd versus first order), and indeed the inductor will generally show poorer transient response during recovery. That coloration may be one reason why some subjectively prefer the high priced spread.
Hi Sy
That is a limitation that I did (explicitly) not include in my analysis. I am strictly concerned about replacing a 5 cent resistor with a gridchoke, with minimal other changes, which is how it is usually done.
Positing the same F3 would require a lot of effort in rolling off the response of the LC coupling as early as is the case with RC coupling.
Sy, I am asking you again, what you write is your best understanding of the subject, after giving it due consideration to the best of your abilities?
Also, please define "poorer transient response" more precisely. Poorer in what way? Like poorer in actually producing a positive grid deflection? Or poorer in what sense?
Now you are making unsupported statements.
Claiming that a given circuit has "poor transient response" is not the same as proving it.
Using such a false assumption as the basis for an explanation is highly unscientific.
You may notice that I am trying to positively commit to a falsifiable statement, that I CAN falsify.
I have no interest to provide proof for statements covered by what you learn in EE101, as I do not consider them to be extraordinary.
It is you who has taken exception to such statements and called them unsupported.
I have posited my contentions.
Do you wish to:
1) Make a positive statement that they are, to the best of your understanding of electronics, untrue? (in which case I may falsify your explicit statement publicly)
2) Accept that they are true and hence publicly retract your earlier comments as a result?
3) Have some time to actually carry out a complete analysis of the posited problems before making any definitive statement on 1) or 2)?
4) Just ignore any inconvenient truth and keep on prevaricating, obfuscating and relativating your previous clear and direct statements when challenged and demonstrate hence to the public your MO?
I await your reply in the best scientific spirit of enquiry and search for actual truth. I would hope you accept my challenge in the same and actually ate a stand.
Kind regards Thorsten
If you have a constant f3 between resistor and choke, the time constant by definition is the same.
That is a limitation that I did (explicitly) not include in my analysis. I am strictly concerned about replacing a 5 cent resistor with a gridchoke, with minimal other changes, which is how it is usually done.
Positing the same F3 would require a lot of effort in rolling off the response of the LC coupling as early as is the case with RC coupling.
The slope is different (2nd versus first order), and indeed the inductor will generally show poorer transient response during recovery.
Sy, I am asking you again, what you write is your best understanding of the subject, after giving it due consideration to the best of your abilities?
Also, please define "poorer transient response" more precisely. Poorer in what way? Like poorer in actually producing a positive grid deflection? Or poorer in what sense?
That coloration may be one reason why some subjectively prefer the high priced spread.
Now you are making unsupported statements.
Claiming that a given circuit has "poor transient response" is not the same as proving it.
Using such a false assumption as the basis for an explanation is highly unscientific.
You may notice that I am trying to positively commit to a falsifiable statement, that I CAN falsify.
I have no interest to provide proof for statements covered by what you learn in EE101, as I do not consider them to be extraordinary.
It is you who has taken exception to such statements and called them unsupported.
I have posited my contentions.
Do you wish to:
1) Make a positive statement that they are, to the best of your understanding of electronics, untrue? (in which case I may falsify your explicit statement publicly)
2) Accept that they are true and hence publicly retract your earlier comments as a result?
3) Have some time to actually carry out a complete analysis of the posited problems before making any definitive statement on 1) or 2)?
4) Just ignore any inconvenient truth and keep on prevaricating, obfuscating and relativating your previous clear and direct statements when challenged and demonstrate hence to the public your MO?
I await your reply in the best scientific spirit of enquiry and search for actual truth. I would hope you accept my challenge in the same and actually ate a stand.
Kind regards Thorsten
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Positing the same F3 would require a lot of effort in rolling off the response of the LC coupling as early as is the case with RC coupling.
Higher f3 = faster recovery, poorer bass. Is that the tradeoff you're suggesting?
I would hope you accept my challenge in the same and actually ate a stand.
No, I actually had a burrito for lunch.
Hi Sy,
What i am suggesting is clearly stated above, in the form of simple direct statements that can falsified or confirmed. You are still welcome to make a suitable direct comment.
Sorry, I meant take a stand. Despite careful checking my lysdexia often catches up with me.
Burrito? Is that kind of Waffle?
Ciao T
Higher f3 = faster recovery, poorer bass. Is that the tradeoff you're suggesting?
What i am suggesting is clearly stated above, in the form of simple direct statements that can falsified or confirmed. You are still welcome to make a suitable direct comment.
No, I actually had a burrito for lunch.
Sorry, I meant take a stand. Despite careful checking my lysdexia often catches up with me.
Burrito? Is that kind of Waffle?
Ciao T
Well, again, if you start with false premises, the questions are meaningless. Please think carefully about the meaning of f3, time constants, what happens after an overload, and the time domain response for recovery. You are not a thick fellow (at least in the mental sense), so I'm certain that you have the equations for corner frequency and Q of an LC circuit committed to memory.
Burritos are wonderful food, especially of the Migas variety, which are a specialty of Austin. As a German/Englishman, you would approve of the potatoes and fat content. However, the spices might alarm you, and the Hatch chiles would be an unfamiliar flavor. Nonetheless, they are a lovely accompaniment to a fine Pilsener (locally, one chooses Shiner), and have the virtue of keeping one filled all day.
Burritos are wonderful food, especially of the Migas variety, which are a specialty of Austin. As a German/Englishman, you would approve of the potatoes and fat content. However, the spices might alarm you, and the Hatch chiles would be an unfamiliar flavor. Nonetheless, they are a lovely accompaniment to a fine Pilsener (locally, one chooses Shiner), and have the virtue of keeping one filled all day.
Sy,
Yes. More to the point, I have build and bench tested such system in practice.
Again, I made several clear statements, for the case of an amplifier having certain electrical properties and offering an "all else being equal" testbed. That is, the only difference is either a 100K resistor or a gridchoke, be that the S&B one, Mike's Magnequest one or the Silk Transformer's one.
If what I have stated is based on false assumptions, or worse, on false observations (in other I was hallucinating when I measured around 30% more power at clipping with grid-choke), it should be trivial to falsify them.
If you wish to commit to clear statement that what I have stated is untrue and not possible according to the basic physical laws governing electronic circuits, to the best of your knowledge, please do so.
If you fail to do so I may just consider that in fact being unable to falsify my statements you choose to deflect from them onto a new topic and will consider that you actually agree they are true and covered by the basic physical laws governing electronic circuits, given the limitations (ell else being equal) I posited.
Note, that F3 and time-constant's are not directly relevant to the statements made. Banging on about them only leads to a note that the -3dB point of the circuit with a gridchoke substituted for a 100K gridresistor is appreciably lower (better part of an octave) than with the resistor, I guess another area where the choke does perform better than the 5 cent resistor.
Non of this is even relevant to the effected debated, namely the reduction or even reversal in what has been called "blocking effect" (which leads to so called "blocking distortion") that choke attains, in contrast to the resistor.
So, what will be? Will you refute my statements, accept them or keep on prevaricating and obfuscating? If the last, have you considered abandoning engineering for politics?
Ciao T
Well, again, if you start with false premises, the questions are meaningless. Please think carefully about the meaning of f3, time constants, what happens after an overload, and the time domain response for recovery. You are not a thick fellow (at least in the mental sense), so I'm certain that you have the equations for corner frequency and Q of an LC circuit committed to memory.
Yes. More to the point, I have build and bench tested such system in practice.
Again, I made several clear statements, for the case of an amplifier having certain electrical properties and offering an "all else being equal" testbed. That is, the only difference is either a 100K resistor or a gridchoke, be that the S&B one, Mike's Magnequest one or the Silk Transformer's one.
If what I have stated is based on false assumptions, or worse, on false observations (in other I was hallucinating when I measured around 30% more power at clipping with grid-choke), it should be trivial to falsify them.
If you wish to commit to clear statement that what I have stated is untrue and not possible according to the basic physical laws governing electronic circuits, to the best of your knowledge, please do so.
If you fail to do so I may just consider that in fact being unable to falsify my statements you choose to deflect from them onto a new topic and will consider that you actually agree they are true and covered by the basic physical laws governing electronic circuits, given the limitations (ell else being equal) I posited.
Note, that F3 and time-constant's are not directly relevant to the statements made. Banging on about them only leads to a note that the -3dB point of the circuit with a gridchoke substituted for a 100K gridresistor is appreciably lower (better part of an octave) than with the resistor, I guess another area where the choke does perform better than the 5 cent resistor.
Non of this is even relevant to the effected debated, namely the reduction or even reversal in what has been called "blocking effect" (which leads to so called "blocking distortion") that choke attains, in contrast to the resistor.
So, what will be? Will you refute my statements, accept them or keep on prevaricating and obfuscating? If the last, have you considered abandoning engineering for politics?
Ciao T
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