John Curl's Blowtorch preamplifier part III

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I had a friend whose first born was consoled only by Baby Baleen while driving in circles around the block.

Ha, when I lived in the USA in 1986 and my first born was 5 months old, I had a beat up old VW Beetle and would drive around Lake Morton in Lakeland, Fa at night to try to get him to sleep. I've driven around that damn lake 6 or 7 times only to go home and his eyes open wide the minute I walked in the door.
 
Neither am I. Richard and Dadod just discovered (the expensive way, unfortunately) the root cause why there are no known power amplifiers on the market with an ULGF of 6MHz or higher. Add testing on a shoestring and you got a safe recipe for a potential commercial disaster.

This is really not fair and very ugly from your side, as you don't know what's really happening with the amp in Thailand.
By the way ULGF is never higher then 4MHz in all variants I simulated of this amp and for the one built in Thailand is 3.4 MHz.
 
You're right. That's the 'little benefit' I mentioned. ;)

"It is not little!" you might respond in disagreement. Well, if someone is relying on the fast A/B switching feature of FoobarABX, he won't perform well.
In your opinion of course.
For example we have one.wav and two.wav. I can play one.wav several times to get used to it, then I play two.wav. Once I know the difference, I can ABX the file by playing only X (or A and X). If I play A I will know if A is one.wav (or not) then I play X and I will know if X is one.wav (or not). Then I don't need to play B and Y to give my answer.

Do you know how it is possible to give answer by playing only X?
Who said the listeners aren't allowed to be prepared before taking ABX? Get used to different examples as much as you want before testing.
 
This is really not fair and very ugly from your side, as you don't know what's really happening with the amp in Thailand.
By the way ULGF is never higher then 4MHz in all variants I simulated of this amp and for the one built in Thailand is 3.4 MHz.
Anyway, apart the insulting "testing on a shoestring" and the definitive "No amp on the market" syn08 seems not to have a lot of experience with CFAs. This is the sim of my working simple CFA amp for treble (without the passive input signal filtering, of course.) Rock stable.
 

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This is really not fair and very ugly from your side, as you don't know what's really happening with the amp in Thailand.
By the way ULGF is never higher then 4MHz in all variants I simulated of this amp and for the one built in Thailand is 3.4 MHz.

3.4MHz is still very high, and, as such, simulations mean close to nothing, in particular for a multiloop compensation network, designed by simulation only. Commercial amplifiers, even the much praised Accuphase CFAs, have ULGFs maximum around 1MHz.

If fact, as already mentioned many times, it is useless to use more than that for other than "because I can" reasons. I've once built an amp with an ULGF of 8MHz, it was stable in the loads I was able to test, but never tried to even post it on my web site as such, but as a more reasonable (for DYI) 2MHz version. The 8MHz is buried on this forum YAP - Yet Another PowerAmp

If you need to blame somebody, blame Richard for mentioning this issue in public, the rest is normal feedback of the "told you so" kind you should expect. I think your BFF Walter mentioned the same, while Bob Cordell elegantly snubbed you.
 
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I’m used to Von Karajan and Furtwangler’s recording races along and to my sensibilities lacks the grace and majesty of the Von Karajan recordings.

H v Karajan was a perfectionist and did care about the whole production from the live performance or studio recording up to the end format (tape, cassette vinyl, CD)

When you want to study conductor’s influence in Beethoven symphonies interpretation, please include Arturo Toscanini in the short list

George
 
Anyway, apart the insulting "testing on a shoestring" and the definitive "No amp on the market" syn08 seems not to have a lot of experience with CFAs.

Ha. Ha. Ha.

No links for you, since I don't want to promote my hobby work in any way, shape or form. Those who want/need, they can easily find it.

P.S. Looking at your pic, until you come up with the details, I have to assume you are confusing the closed loop gain/phase with the loop gain/phase. Mind you, this is not potatoe/potato difference, but don't worry, you are not alone in such confusions. And even so, I doubt this is a power amplifier.
 
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Ha. Ha. Ha.

No links for you, since I don't want to promote my hobby work in any way, shape or form. Those who want/need, they can easily find it.

P.S. Looking at your pic, until you come up with the details, I have to assume you are confusing the open loop gain/phase with the loop gain/phase. Don't worry, you are not alone.
So, why do you wrote those aggressive comments to Dadod and Richard works ?
(sim square waves of my amp)

PS: No i don't confuse. Just too lazy to make a Trian prob just for the pleasure of arguing.
 

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If truth is aggressive, then so be it.

Square wave showing the slew rate have nothing to do with the amplifier ULGF. ULGF is a small signal property, slew rate is a large signal property.
This not the slew rate. Slew rate has to be made in saturation mode.
BTW: I have no overshoot in little signals as well that's the way I compensate my amps.
This said, it is not the subject: Dadod had answered-you about the ULGF of his amp. Pretty amazing, if we consider the complexity of his work and the various various originalities of his demarch.
 
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This not the slew rate. Slew rate has to be made in saturation mode.

With all due respect, you have no idea what you are talking about. Please stay with the subjective prose, you are at less risk to make a fool of yourself.

PS: No i don't confuse. Just too lazy to make a Trian prob just for the pleasure of arguing.

Yes you do; whatever curve is the loop gain, it would mean your closed loop amplifier has virtually no feedback.

And once again, this is not a possible physical power amplifier. A 22MHz crossover frequency (if I'm reading right) is impossible to build, even in simulation (with real device models). If you want to be taken seriously, come up with a schematic, and somebody will point you to what you are doing wrong (in simulation, of course, as I don't think you had the chance to build it).
 
We definitely need an help from Markw4 on the best way to begin...

Seems to be more interest than I expected. Just heard from JC on the phone. Probably better to take it up in the dac thread where I am most active. Please ask about whatever you are interested in, be it the best way to begin, or your choice of dac topic. ES9038Q2M Board Don't worry what other people will think, is all I can say. People ask all kinds of questions such as how to begin, and so on. I would suggest a good way to begin might be to conceptually follow along with the steps for modding a very low cost $39 dac board into a pretty good one. That should lead to a pretty well rounded practical dac discussion, IME.
 
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I had a friend whose first born was consoled only by Baby Baleen while driving in circles around the block.
It's Beluga, but close enough :)
H v Karajan was a perfectionist and did care about the whole production from the live performance or studio recording up to the end format (tape, cassette vinyl, CD)
Whilst Kudos for him having his own recording studio the perfectionism was exactly why I personally rarely listen to any Karajan recordings. Some see Majesty, I see sterile perfection, multimiked to death and cut and spliced to get the note perfect performance lacking in any emotion.

Karajan is almost diametrically opposed to Furtwangler so I guess you can't like both :). One was the last of his kind, the other the start of the 'safe' school of conducting we have today.
 
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