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Old 22nd March 2004, 08:11 PM   #21
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Join Date: May 2003
Location: Morton, Illinois
Default Caught yourself again

Well, we can point out some more distortions, misinformation and maybe an outright lie from Thorsten. Of course he continues to evade and sneak around, trying to avoid the questions I have put forth to him. But this time he even puts down his own system. Read the details below.

The FR is as I stated, you cannot sneak out of this one. It is-.5db around 5khz, -1db at approx 10khz, very poor. As before, I built this circuit and tried it years ago. It beats some SS designs.

In your dreams Thorsten. You can't sneak out of this one. I already asked you to explain it several times, but you can't.

<It would be easy to change the open loop response to a much wider one by lowering the impedance values in the feedback setting circuitry and by using a lower resistance volume control. If we (for arguments sake) lower all values by a factor 10 we can easly achive a ridiculously wide bandwidth, which has no advantage whatsoever (sonically or other) and introduces a number of other problems. >

Caught yourself again.
First. Only after I mentioned it in my post do you now mention opening the bandwidth.

Second. Then why didn't you design it with better open loop response (except for interference problem areas) to begin with. Afterall, according to your own words, it doesn't make any sonic differences. It would at least look better on paper to the critics.
Actually, there are differences between the designs, but you don't know it. You lost again Thorsten.

****You cannot discern any sonic differences between the two feedback preamps with either wide and narrow open loop bandwidth. Way to go Thorsten, cut your own system down. Thanks for the help Thorsten.

<It is my experience that a well implemented and sensibly set bandpass behaviour is preferable in linestages, arguably a sentiment open to discussion, however I usually follow my own design requirements when designing something.>

So how can you tell when your system can't reveal the difference between two feedback preamps with different open loop FRs. Does either sound like a straightwire with gain?
Looks like you just made up another story.

<quote:
Originally posted by Positron
Well, give me a wrong way to use the feedback in a single stage preamp. It isn't hard to do correctly, or at least as best as is possible.


Is the above your opinion or are you stating a fact? If you are stating a fact, would you mind illustrating WHY applying loop feedback to achieve low gain and to take advantage of the stages excess gain to improve linearity and lower the outputimpedance is "a wrong way to use feedback"? Maybe you would like suggest the "right" way to use feedback?>

Caught yourself again.
You can't even show me a wrong way to connect negative feedback to your circuit. I have asked you several times to explain the inners of feedback but you couldn't, so don't ask me now. And you are Newton??

<You build a Circuit I published here a few days ago DECADES AGO, with identical resistor, cpacitor and other values? Interresting feat. I now would also ask for plans to your time machine, I could use one.>

Interesting that what you condemn me of is exactly what you did in past strings, condemn my components, tubes I use, and me without ever hearing them in my designs. You sound like a shill.
The difference is you have only 2 years experience vs 44 years for me. So I have much more accumulated knowledge, listening experience, testing many more designs (each of which I have used a vast number of parts etc) than you have. You can't sneak out of this one Thorsten. Nailed ya again, Newton.

How about some names hotshot. And how close are the designs?


<Actual measurements Thorsten. I am certainly not going to give you a schematic to copy and waste decades of private research.
Of course this is how a typical con artist works; trying to steal a design instead of paying for it. Typical shill attitude.

By the way, I just recently got the latest review from BFS, who accepts no kickbacks or advertising, on my preamp. What reviews do you have on yours??

<Well, first, are your actual measurement independently verified?>

Where is the review Thorsten?? Come on now. Stop hiding.

By the way, there are many over the years who have seen my testing, actually watched.


So what is your point? Does it sound like a straight wire with gain? Have you even actually tested it for such?


The question was in your design, not a two stage design or multiple poles. You can't seem to answer a simple question. Are you simply quoting from a book in front of you? Otherwise why mention a completely different circuit? That is it, he has someone or book in front of him.


<I would consider making deliberatly misleading statements (eg claiming a circuit that has illustrably a frequency response of -1db @ > 40KHz has one of 1db @ 6KHz) both unethical and deceptive.
Of course, it seems you call that behaviour ethical and truthfull. I must insist that this is where we part company. ">

Interesting since you were the one who refused to devulge your unethical behaviour until I asked twice, and constant lies and deceit, including the ones in this string I have caught you in. And you are saying I am unethical because I tricked you into divulging a 16db feedback you were trying to hide?

<WHAT unethical behaviour?>

Everyone who has been reading these strings have seen the lying, deceit, and unethical behaviour you have consistently shown. Don't get mad at me when your world collapses on your head. You did it to yourself, with no one else to blame.

<Correction. The open loop response is poor in your considered opinion, whereas in my case I consider it adequate and a good compromise between a number of conflicting design requirements. We can argue endlessly about what is the better compromise, the choice is in the ear of the beholder.>

Wrong again Newton. The straightwire with gain is the standard, not your opinion Newton, and not mine. And the open loop, or closed loop response of the preamp sounds poor by that standard. You can't sneak around that; lost again Newton.


<Nice excuse for incompetence. It would ring truer if you had less of a history of completly ballsing up on basic electronics. I took the time yesterday to review a decent number of posts by you. I rarely seen as many mistakes in basic things from anyone having at least basic competence in electronics. I had more than a few good laughs on your account.>


Why didn't you give an example now? Bring it on hotshot. Of course we both know you are a liar and shown you know very little.
Very interesting since you didn't understand the problems with your preamp design until after I mentioned them; and you still can't go any deeper into the design. Keep making a fool out of yourself Newton.


<But truth is, what is the point if an illiterate peasant pays backhanded compliments to Newton?>

You're Newton?? You can't even answer indepth questions about your own preamp, know how to apply feedback wrongly in your design. I had to get you to admit to the 16db of voltage feedback you were trying to hide if you even knew about it.

Everyone who sees this post will forever link you to your own Napolean complex, total arrogance, and total absurdity, besides total stupidity. Wow! And a audio mag let's you review??? Of course do they know you are being compensated under the table, and tried to hide it? Isn't anything about that unethical... "<WHAT unethical behaviour?" ...the answer to your above question that you try to hide time after time?

<How about you do so, making sure your math is actually up to scratch and your computer program can at least divide correctly and you math is based on reality not wishful thinking.">

Remember I am finding out what you know;

I notice. But don't expect much else from here.">

Of course we all know you have had help or bluffing your way through.

<Well, it seems that you spend a lot of time and work to fail to know even the basics of electronics. I shall take in the next few days take the time to illustrate this a bit further (I'm actually going to enjoy that) and collect your various psotings of great wisdom over the last few month which demonstrably show an appaling lack of being able to apply basic logic and evaluating basic electronic circuits. And not forget the public (re) posting of some of the olded urban legends in the book, that was priceless.>

Why didn't you bring one forward? Lying again are we? And are you going to misstate my positions again like I caught you doing in a previous string? Remember, completly the opposite what I had stated. Isn't that called a bold face lie? Unethical if I remember correctly.
But don't blame me when you continue to sink yourself.

Who is going to believe your reviews anymore??

Bye bye Newton
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Old 22nd March 2004, 09:41 PM   #22
Previously: Kuei Yang Wang
 
Join Date: Nov 2002
Default Positronic Pearls of wisdom....

Konnichiwa,

First the one that really had me in stitches:

http://diyaudio.com/forums/showthrea...399#post341399

"Please read. Post #1

Although not audio related, I thought I would relay this from my sis, a school teacher.

Subject: Police Warning

POLICE WARNING,

ONE OF THE OFFICERS WHO WORKS WITH THE DARE PROGRAM HERE IN SHREVEPORT HAS PASSED ALONG THE FOLLOWING WARNING AND ASKED THAT IT BE SHARED WITH ALL DRIVERS. THIS IS AN EXTREMELY SERIOUS MATTER. "

Following on from that is a rather old hoax, I mean not even something current, but ancient, from around 10 Years ago.

http://www.snopes.com/horrors/madmen/lightout.asp

And prior to being moved "off topic" this was actually posted in the "Tubes" section.


But of course just because someone does not have the common sense to spot ancient hoaxes does not mean he is bad at electronics. So, any really basic gaffes there? How about this:

Someone asks about a sonic problem with his kit preamp:

http://diyaudio.com/forums/showthrea...057#post348057

To the rescue our intrepid positron, exposing medocre design where he sees it:

http://diyaudio.com/forums/showthrea...996#post348996

"Hi James,

Looking at C18 (and R16, 10, 11), no wonder it sounds thin. Should be much larger if you want descent lows and flesh on the "faces". The other two caps also form high pass filters too."

Let's see, the circuit around the second halve of V1 is a bootstrap follower, a circuit well known to anyone who has done any significant work wth valve equipment. It's key feature is a very high input impedance, theoretically infinity, in reality several times the actual value of R10. HOWEVER, even IF R10 was determining the LF cutoff of the highpass, would that be a problem? If we multiply 1000k with 68nF we get a timeconstant of 68,000uS, equal to a frequency of around 2.33Hz.

No wonder it sounds thin, the LF output is 3db doen at 2.33Hz (except it isn't, it is 0.3db down at 1Hz!!!! - [per P-Spice which on such things is jolly close]). And of course he cannot omit a cheap snide snipe either:

"If I remember correctly, Velleman is rather inexpensive, so you may not be able to do alot without major modifications."

Read "You bought cheap crap, you will have to live with it".

Luckily enough some others where there to correct him before the poor guy james run away with this piece of "good advise" and would of course find no improvement whatsoever. So, okay, Positron admits he was wrong (heck, he was at least a magnitude or two out...), but plots revenge, after all, it must be a RC higpass that causes this....

So we get:

http://diyaudio.com/forums/showthrea...059#post349059

"R15 should be increased, will help the bass response and add "flesh" to the voices. Might first try a large value, say 220k and see if it is ok or is too full. If to full, then back off the value till it satisfies your tastes. "

Hmm. At first look R15 looks a little low in value. And indeed, it would not be my choice to achieve what the Velleman designer has done here in that particular way. However, Positron does not assert that the problem is the main effect caused by R15 being low in value (and which is at least partly the reason for the "washed out, bright sound"), but he asserts that the low value of R15 cuts the Bass.

Well does it? If we multiply 4700nF with 5.6 Kohm we get a 26,320uS timeconstant. This corresponds to a 6Hz -3db point, but because we have this whole thing attached to a bootstrap follower and not a normal cathode follower the actual -3db point is at 5.5Hz (per P-Spice which on such things is jolly close) and at 20Hz the LF rolloff is -0.3db (per P-Spice).

Even with an added external 10K load the -3db point is at 8Hz and 20Hz is only 0.6db down. Hardly spectacular stuff, but miles better than pretty much any funloving loudspeaker you care to name.

I think the "R15 is too low and hence thins out the bass" brainstorm can be safely put to rest. Now MAYBE, just MAYBE Positron actually caught on what really happens and just wants avoid showing how smart he is and hence suggest to do the right but claims the wrong reasons?

Well, he has the last word in that thread:

http://diyaudio.com/forums/showthrea...488#post349488

"R15 is the real problem, much too low. Creates a high pass filter and thus limits bass and extends sonically to the midrange sounding thin."

Well, clearly, he has not cottoned on as to what is happening. He insists on the "Highpass set at too high a frequency" to the last. Well at least he is consistent.

More pearls of Positronic wisdon another time. At least now I know what the guy meant when he quipped "Artificial inteligence is to real intellgence like artificial flavourings to real flavours".

Sayonara

PS, the solution to the riddle of the bright sound?

Have a look at what heavily loading a cathode or bootstrap follower does to the distortion pattern (especially complex IMD).

The Velleman designer deliberatly loads this stage down to get a certain sonic effects by raising distortion, sadly doing it the way it is done here also leads to other sonic effects, namely usually a somewhat less than pleasant sound.

So, loads of points for effort positron, zero points for circuit analysis - my old tutors would so much have failed you in EE101, it is not even believable.
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Old 22nd March 2004, 10:36 PM   #23
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Hi,

Quote:
Have a look at what heavily loading a cathode or bootstrap follower does to the distortion pattern (especially complex IMD).
The CF on it's own wouldn't survive any real world testing regardless of the size of R15.
Whenever it's required to deliver some current into a load it will inevetably collapse trying to steel from the anode follower.
This is one type of CF that should be avoided to drive difficult loads.

Loading it down already, hence drawing an almost constant current makes it look better in isolation but perform even worse in the real world as it will now have nothing left to "steel" from.

Add to that the bootstrap positive feedback_ which you can really do without here_ and you really wonder what on earth they were trying to achieve.

To add further insult to injury, a quick look at the distortion spectrum of a garden variety ECC82 will reveal it's already anemic condition to the point that it almost always sounds shrill and lifeless.

In the case of the Velleman circuit_ I'd like to know that Belgian designer, or maybe not_they made every conceivable effort to make matters worse.

So real estate permitting; get rid of the bootstrap by tieing R10 straight to ground, change R15 to about 100K and maybe, just maybe it would be a little better.

At least that's what I'd do facing a crying customer.

Cheers,
__________________
Frank
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Old 23rd March 2004, 12:45 AM   #24
DougL is offline DougL  United States
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Kuei Yang Wang;

Konnichiwa,

I always learn something from your contributions.

The design you presented had a couple of features that I wanted to ask about.

It looks like each tube is only biased for about 110 Volts and 3.2 Ma current. This is very conservative.

Also, I notice that with 16 DB feedback, the maximum voltage swing in the negative direction is only about 8V.

The Analysis is via Tube Cad, which seems good for quick approximations.

Respectfully;

Doug

By the way, I will Propose something in the other thread.
Only fitting.
Please feel free to comment.
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Old 23rd March 2004, 01:42 AM   #25
Previously: Kuei Yang Wang
 
Join Date: Nov 2002
Konnichiwa,

Quote:
Originally posted by DougL
It looks like each tube is only biased for about 110 Volts and 3.2 Ma current. This is very conservative.
Yes. You will find that in most cases my operating points are VERY conservative. Rare NOS valves last longer that way and to my ears sound better.

Quote:
Originally posted by DougL
Also, I notice that with 16 DB feedback, the maximum voltage swing in the negative direction is only about 8V.
I am not sure how you arrive at that conclusion. The maximum output voltage swing remains what it is prior to applying negative feedback, which is well past 20V RMS. Remember, this is an inverting amplifier, where the grid voltage is in effect the "error voltage" between the ideal "zero" with an amplifier having infinite open loop gain and our real Amplifer. Unlike some other topologies shunt feedback as seen here does not compromise the input dynamic range, it is increaed in effect by the feedback factor.

Quote:
Originally posted by DougL
The Analysis is via Tube Cad, which seems good for quick approximations.
Not sure how accurate Tubecad models this specific topology. I don't have it or use it, having learned P-Spice ages ago and thus being non too willing too change. I have fond P-Spice to be usually "very close" in many cases, the exceptions being such items as grid current and other "extreme non-linear" operation conditions.

Sayonara
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Old 23rd March 2004, 01:42 AM   #26
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Join Date: May 2003
Location: Morton, Illinois
Default Way to go.... eats crow again.

Well, as usual, you made a big fool out of yourself. Let's take a deeper look.

The first, a warning, not audio related:

First off, I love my tube buddies and wanted them to be warned. They might not see the post in another venue. Secondly, you are laughing about something that is real. I have a friend whose son, a Chicago postman, who was shot several times on a busy street by someone jumping out of a car, in broad daylight. It was an initiation for a teen. He survived. By the way, the dads daughter is a police officer up that way and things are pretty nasty. If you think this is funny, that is your problem Thorsten. I was concerned for my friends. I don't keep up on hoaxes. Your comments really show what you are really like. What a shame.

Now let's look to the audio postings.

"Hi James,

Looking at C18 (and R16, 10, 11), no wonder it sounds thin. Should be much larger if you want descent lows and flesh on the "faces". The other two caps also form high pass filters too.

Increasing C18 will help lows but be careful of possible motorboating from weak power supply design. If this happens, will have to lessen value of C18. Would try to give it 6db leeway in this regard.

Also might try getting rid of C17.

If I remember correctly, Velleman is rather inexpensive, so you may not be able to do alot without major modifications.
__________________
Take care.

Steve"

"R15 is even worse, 5.6k?! Increase it alot, even to 220k or more if desired without harm, and see how it sounds. Shouldn't be any motorboating problems as this resistor is "out" of the circuit design that could cause motorboating.

Touch up C18 later, if you need to.
__________________
Take care.

Steve"

"Dear Frank,
I think you are correct. Sorry about the mistake.
Is C18 68000pf? Looks like it to me. If so, it should be ok.

R15 should be increased, will help the bass response and add "flesh" to the voices. Might first try a large value, say 220k and see if it is ok or is too full. If to full, then back off the value till it satisfies your tastes.

Thanks for catching my mistake Frank.
__________________
Take care.

Steve"

"R15 is the real problem, much too low. Creates a high pass filter and thus limits bass and extends sonically to the midrange sounding thin.
__________________
Take care.

Steve"

1) So first off I don't see a page 2. Ok, now: "Read "You bought cheap crap, you will have to live with it"? I don't see where I said that. I was trying to be kind. That sounds pretty harsh to me. I wouldn't have offered suggestions to improve the bass, and mids if I didn't think it might not work.
Secondly, changing a cap is rather major, esp to a newbie (if he is one). He might also remove C17 which is major, get into the chassis project. These aren't minor like changing a tube. However, if he took it that way, my sincere apologies to James.

2) Where did I make the comment "No wonder it sounds thin, the LF output is 3db doen at 2.33Hz". I don't see this either on my posts. Does anyone else?

3) The schematic was hard to read, and I didn't want to cause waves with Frank, he is valued by me. So I let it go. But C18 is really too small at .068uf. Why? Well, if Thorsten had actually done any testing, and new tubes as he says he does, he would have known the reason.

A) "It's key feature is a very high input impedance, theoretically infinity, in reality several times the actual value of R10."... is not necessarily true.

There is a very, very, very small amout of grid current, varies by tube, the remnence of contact potential and impurities, depending on the tube type and manufacturer, and C18 is rather small to handling this problem. As a result, depending on the tube, the sound changes not only the bass, but the midrange and highs too. I have seen this problem, but you didn't know this with your lack of experience. If the capacitor was a larger value, the tube would have more leeway in regards to grid current variation in production, so generally no worries unless the tube checks grid current on a tube tester.

B) The midrange/high problems could also be the construction of the capacitors. Thus several aspects can be in play.
However, looking at the circuit closer, which I apologized for not doing, revealed R15 to be a/the major problem. In fact R15 is ridiculiously low for high fidelity without even doing any math. A total screwup in design, for accurate reproduction that is. I have to admit I didn't look twice at this part of the circuit as no one pulls a stunt like this, at least I thought not. Thanks to Fd for making me take another look at this design. This low value not only loads a cathode circuit, but also just about any plate output circuit as well. It is suppose to be high fidelity, it shouldn't have had this low value.

<"Luckily enough some others where there to correct him before the poor guy james run away with this piece of "good advise" and would of course find no improvement whatsoever. So, okay, Positron admits he was wrong (heck, he was at least a magnitude or two out...), but plots revenge, after all, it must be a RC higpass that causes this....">

As usual, you stuck both feet in your mouth, Thorsten. But let's continue.

<"R15 should be increased, will help the bass response and add "flesh" to the voices. Might first try a large value, say 220k and see if it is ok or is too full. If to full, then back off the value till it satisfies your tastes. "

Hmm. At first look R15 looks a little low in value. And indeed, it would not be my choice to achieve what the Velleman designer has done here in that particular way. However, Positron does not assert that the problem is the main effect caused by R15 being low in value (and which is at least partly the reason for the "washed out, bright sound"), but he asserts that the low value of R15 cuts the Bass.

Well does it? If we multiply 4700nF with 5.6 Kohm we get a 26,320uS timeconstant. This corresponds to a 6Hz -3db point, but because we have this whole thing attached to a bootstrap follower and not a normal cathode follower the actual -3db point is at 5.5Hz (per P-Spice which on such things is jolly close) and at 20Hz the LF rolloff is -0.3db (per P-Spice).">

Well, again showing your total lack of testing and experience. "A little low"? If you had actually checked, you would have found the time constant you mention cuts the bass dramatically vs a straightwire. Now add two more caps, and time constants, in this one tube stage alone, and you have a real problem with the bass.
Secondly, when the bass is cut, the mids thin out (washed out) and the amp can sound bright as well (also depends on the construction of the caps).

<"I think the "R15 is too low and hence thins out the bass" brainstorm can be safely put to rest.">

Of course Thorsten doesn't know what he is talking about as if he had done any basic/elementary testing of coupling designs, he would have found R15, C21 to be very weak in the bass region. Combine this with the two other coupling cap time constants and the plate circuit, and well...... Thorsten, you screwed up again as usual.

No wonder audio doesn't get any better.

<PS, the solution to the riddle of the bright sound?

Have a look at what heavily loading a cathode or bootstrap follower does to the distortion pattern (especially complex IMD).

The Velleman designer deliberatly loads this stage down to get a certain sonic effects by raising distortion, sadly doing it the way it is done here also leads to other sonic effects, namely usually a somewhat less than pleasant sound.>

Reducing the bass also thins the mids, lack of flesh type of sound.

<So, loads of points for effort positron, zero points for circuit analysis - my old tutors would so much have failed you in EE101, it is not even believable.>

Really? Interesting that my suggestions have fixed all the problems. I could have told you so and saved you alot of trouble.
And you got it wrong. And of course, you would have stuck with C18, but I am not going to quibble of that.

Hey, I thought you were telling me not to make major modifications!!! Yet what are you asking for, major mods??? Or nothing and leave James hanging?
And that I was calling his stuff crap (I was trying to be nice)? Yet you are cutting Jame's heart out. Why not do what you preach at me??

In conclusion, my suggestions were correct. If my advice were followed, James wouldn't have been hurt, the amp would have sounded better, and any minor tweeks could have been handled later, and Thorsten wouldn't have made a total fool out of himself again. Thanks Thorsten for all your trouble. It really helps audio.

Now just slink away in your shame.
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Old 23rd March 2004, 09:27 AM   #27
moamps is offline moamps  Croatia
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Join Date: Oct 2002
Location: Croatia
Hi,

Schematic below is from Rainer zur Linde's book "Build your own Audio Valve Amplifiers". WWW source is http://www.bonavolta.ch/hobby/en/audio/lindelin.htm

I have this book, measurements look good (-3dB at ca 30kHz, distortion below 0,1%), schematic looks very close to Thorsten's design.

Comments?

Regards
Attached Images
File Type: jpg linde.jpg (60.6 KB, 352 views)
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Old 23rd March 2004, 02:28 PM   #28
Previously: Kuei Yang Wang
 
Join Date: Nov 2002
Konnichiwa,

I amused myself a little bit more following the footprints of Positron. Very interesting. I can now understand why he is bitter. Well, a few more bit's of wisdom first....

http://java.audioasylum.com/cgi/m.mp...Steve&session=

"IDT triode (indirectly heated triodes )SETs offer broader frequency response without compromise than other SETs which are often +/- db which really means -db times two. Bass and highs more extended and more accurate. No hum problems a big plus because lower level nuances come through without hum masking. "

There are several claims rolled into this, the main thrust is (as usual) to suggest that DH Valves are technically inferior, we will soon see why this bothers Positron so much, but anyway...

The first claim is that depending upon the fact that a strean of supoposed electrons is emitted from a suitably doped metallic cathode sleeve or from a suitably coated wire we observe a difference in frequency response. Now here someone is getting desperate. How on earth can anyone in their right mind and with any even most basic level of electronic knowledge make such a gaffe? The frequency response is of course determined by the circuit design, not by the device itself.

The next claim is that using DH Valves invariably gives rise to hum.

Well I have build DHT Amplifiers with demonstrably and measurably < 0.2mV output noise without using extreme measures. That level of noise BTW being almost purely 50Hz from magnetic coupling into the Drivers anode load choke and nothing from the output Valve. Now 0.2mV is 83db below 1 Watt and on the specific Amplifier it would translate to 92db below nominal output.

I have build DHT Amplifiers where I took extreme measures and got the output noise to nothing but the drivers (5842) self noise, which made it difficult to see anything even with a sensitive 'scope.

So, DHT's cause hum? If you are an incompetent designer they sure do.

Let's move on to (mostly) character references for Positron. I'll let these speak mostly for themselves:

http://java.audioasylum.com/cgi/t.mpl?f=set&m=27217

"Before I even knew AA existed, I got an email of someone copying part of my webpage, and some crucifying it. That is how I found AA. I never criticized DHTs cause I didn't even know they were being used, let alon a big deal."

Hmm, at the time claimed 41 Years experience but never noticed DHT's.... Sure.

http://java.audioasylum.com/cgi/t.mpl?f=set&m=14313

"Well Tom. The impression I get is that me and others are idiots if we don't use DHTs."

"Then why was there a deliberate attempt at driving IDT people out of AA? I saw so much misinformation, propaganda and I have downloaded many of these postings. I saw so much harrassment against IDT owners, trying to squash any influence at AA."

http://java.audioasylum.com/cgi/m.mpl?forum=set&n=10750&highlight=SAS+Steve&sessio n=


Steve from SAS audio labs writes

"I can't even purchase transformers from one company, not that I want to now, because a DHT man blackballed my company, before I knew of AA or DHT company competitors. See where I am coming from? I was strictly trying to get a business going"

"But misleading, ignorance, or lying in a posting misleads, is close to fraud and just isn't right. All these horrible postings are phychological warefare."

jeff mai:

"I hope you aren't referring to our friendly exchanges, Steve. My specific dispute is with your claim that a triode connected KT88 has lower distortion than a 300B. I've repeatedly asked for proof of this and I'm still waiting. There is no lying, misleading or hate here; just a desire for the facts to be known."

Steve from SAS audio labs writes

"I actually measured it in a low distortion circuit. That is proof."

"It also seems to me that the so called "friendly" postings were not friendly but attacking my products."

"Another interesting point, BFS listed only my SE7.0W from 1999 in the review of the Edgarhorn slimline and not yours."

(Note - Jeff Mai is a DIY Enthusiast, no a manufacturer!!!!)

"SEE DAVE what I have been saying. Go back and look at how many postings where they said the KT88s had higher distortions than the 300b and 2A3s etc. There were several. I never posted first, just them. Yet it turns out my measurements from an actual distortion analyzer showed the KT88 to be lower. SEE DAVE what I mean. There is obviously bias and an adgenda here."

(Note - "SEE DAVE" is an appeal to the Moderator)

jeff mai:

"Disagreeing with you is an act of hate????? Asking for legitimate proof is an act of hate?????"

"What I do disagree with is your claim that a KT88 has lower distortion than a 300B. That's all; plain and simple. You offer the data on your web site as proof of your claim. By your own admission, this web site lists distortion figures for the WE300B that come from Western Electric's data sheets."

"This data was either measured or calculated for the 300B output tube in isolation. The data you provide for the KT88 is at the output of a complete amplifier. Because of this, comparison of these two pieces of data are not meaningful, i.e. you're comparing apples to oranges. For pointing this out, you accuse me of hatred and lies?????"

(Note - a common theme - as soon as someone disagrees with Steve he obviously is atticking him and his products and must by definition be a lier)

In another context further up the thread:

Steve from SAS audio labs writes:

"It is obvious some never wanted a good relationship with any IDT as it would hurt business. But blackball me from getting a certain brand output tranny is pretty sad. "

"Then the reviewer only heard the hum when he sat in his listening position, I believe 8 or 9 feet away. It was amazing how the postings in AA didn't even mention this and how those same postings were deleted when going into the archives."

mobile homeless writes:

"Lordy, Steve... Not quite sure what you are talking about here as it took me aproximately 15 seconds to find that amp and posts in question. Indeed, I was involved in the exchange and I dont remember anything deleted. In fact, if you look, Gordon even posts the name and location of the Neil Muncy paper concerning the grounding scheme."

"Gordon goes farther to admit it made for good reading and included some good ideas etc. He also discusses the perils of a piece of equipment going to Stereophile and how sometimes things dont turn out there as they were in your designers system. On the whole, that amp you are referring to received a GLOWING review.

(Note - So, who is lying?)

Steve from SAS audio labs writes:

"Attacks that I was lying, cheating etc. And I didn't see more than one posting supporting the measurements and the truth. Just pure hate to try to discredit me."

Tom$ (Moderator IIRC) posts:

"The "untruthful attacks"? Are these the posts you obliquely refer to?"

"http://www.audioasylum.com/forums/set/messages/10249.html"
"http://www.audioasylum.com/forums/set/messages/10256.html"
"http://www.audioasylum.com/forums/set/messages/9989.html"

"Seems to me you just have a personal grudge against Jeff Mai, Rankin, and an unnamed person in an e-mail. Why attempt to damn AA as a whole if your beef is with 3-4 people?"

Dave VH (Moderator IIRC) posts:

"It is not the facts that have gotten you into this deep quagmire, but the way you handle people. Only you can control the way you interact with others, and I see no evidence that you are capable of diplomacy and tact. You seem to believe only in attacks and counterattacks, and as long as that happens, you will be engaged in perpetual ****ing contests."

"Me thinks that you should consider changing your strategy."

Steve from SAS audio labs writes:

"I haven't seen anyone use the KT88 properly yet."

I'd also recommend to review the following threads as well. I think from the above and those threads the agenda becomes very clear.

http://www.diyaudio.com/forums/showthread.php?postid=304076#post304076


http://www.diyaudio.com/forums/showthread.php?s=&threadid=26654


I have no conspiracy theories and I am in no conspiracy against the SAS Labs products, no matter what Positron thinks in his acute paranoia and alledges. I also do not suggest that Positron orchestrates a consistent campaign against DIY, DHT's and the like, far be it. I leave that to others.

Sayonara
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Old 23rd March 2004, 02:41 PM   #29
Previously: Kuei Yang Wang
 
Join Date: Nov 2002
Konnichiwa,

To close of this whole positronic affair, a few closing remarks.

My considered opinion is simply that the man fell off the deep end when he noticed a lost opportunity to drum up busines and has now paineted himself into a corner wher ehe must continue to bash DHT's, DIY, people by far smarter and more experienced than he is.

And no - I'm not talking about myself (my experience with valve audio only goes back to the time I was around 8 or 9 Years old, an event only two years in the past as we have observed from Positrons postings) but people like Lynn Olson, Gordon Rankin and others whose fault it was to champion DIY and to suggest approaches Positron does not like.....

I do not think posting completely unprovoked comments like:

"I read the Lynn Olsen article for about the 4th time, and I would say some of it is utter nonsense. I would be careful about believing everything he says."

http://www.diyaudio.com/forums/showthread.php?postid=268877#post268877


sow either respect or consideration for others (any others) nor does it show particulary good ethics if what you are actually doing in effect is diss a competitor, a priori, without provocation and quite deliberate.

Oh, the later comments also show an appaling lack of experience and electronic knowledge, but that baby has been long poured out with the bathwater anyway.

Well, I shall call it as I see it. Sour Grapes, in my opinon.

Other people are sucessfull selling Amplifiers that he doesn't like to customers that he feels should rightfully be his customers. But according to him his rightfull customers are being misled by people like me via a concerted campaign of misinformation and hatred into buying DHT Amplifiers or (shock, dread) going the DIY route.

He appears to feel that this is costing him sales that are rightfully his. If so, why not sue? If you have a right to those peoples custom, sue the them for not buying from you, Steve! They can then sue people like me for giving bad advise after you won your case!

A quote again:

Steve from SAS audio labs writes

"See where I am coming from? I was strictly trying to get a business going"

Yes, I can see that. And still trying? No such thing as bad publicity?

My advise, stop arguing with others about why your products are so great and their own products (if they be such - remember, this is DIY Audio so few if any of the designs discussed are commercial), simply keep making them and if they are any good they will sell.

If not, well, as the Rabbi said to the Irish Catholic priest, "Life is short and Sh*t happens".

It is my considered opinion that Positron went way of the deep end and simply cannot handle reality. There are (mental health) professionals who can help, even in cases of extreme and unjustified paranoia like this one.

I do take his allegations of unethical behaviour on my part as very serious and will ask him here and now for PROOF that I have done any of the following:

1) Lied in any of my postings (he forgot to add "In my opinion" to "He lied", I do not give a nickel for his opinions, but he stated this as fact)

2) Misstated his posted texts (whatever position he may wish to convey is one thing, I have to go by what is written)

3) Directly attacked his company or products (as opposed to his views and opinions - such an attack would read "Amplifier XXX from Company YYY sounds bad because it uses Tetrodes - where XXX is his model and YYY is his company).

Well, on the other hand I might actually consider being singled out by Positron for the "third degree" a badge of Honour. At least I'm in excellent company.... ;-)

Sayonara
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Old 23rd March 2004, 02:55 PM   #30
Previously: Kuei Yang Wang
 
Join Date: Nov 2002
Konnichiwa,

Quote:
Originally posted by moamps
Schematic below is from Rainer zur Linde's book "Build your own Audio Valve Amplifiers". WWW source is http://www.bonavolta.ch/hobby/en/audio/lindelin.htm

I have this book, measurements look good (-3dB at ca 30kHz, distortion below 0,1%), schematic looks very close to Thorsten's design.

Comments?
The input Lowpass (Pot & R1 with C1) would seem to dominate the circuits upper cutof. I personally would likely prefer a little wider frequency response (closed loop) which can be achieved by reducing or omiting C1.

With C1 omited I'd expect the Circuit to have a very wide bandwidth, far past -3db @ 100kz which i normally consider easily good enough for human consumption.

Otherwise the parallels with the looped feedback, single stage design I suggested are obvious, similar design approaches are employed. The can also be found in old Citation preamp's, many DIY gear going back into the 1940's and the like. They are generally well understood and quite common. But anyway, I never claimed that the design was particulary special, it's more like "proven in the last 50 - 60 Years"....

Sayonara
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