John Curl's Blowtorch preamplifier part III

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You would most likely be disappointed, they are pretty much related to nothing but hardcore technical stuff. I know of no instance where listening to design options led to any engineering change. Our listening room soon degenerated into a makeshift studio to film employees for Youtube adverts.
Not so different from the snake oil sellers approach: Money and sells before search for perfection. The only difference is AD provide... more measurements and less poetry ;-)
With time I noticed AD (and all others) provides ... less and less technical datas in their sheets and more and more ... poetry .
 
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Proof ? A simple and logical reflection is not enough for you ?
of course, if you want to make sure to not be under some influence, you need to ignore the brands or model of what you are comparing.

If you never know what (anonymous) source is playing , you cannot correlate successive feelings. So you need to ensure that, when you are noticed the A or B is playing, you need to ensure A and B are always the same device. And we need this, because we need both time, repetitive listening and various imperfect (they all are) sources to refine our jugements.
Too, comparing more than two sources at once is to complicated and confusing for our memory.
Adding that those blind tests are both boring and tiring, from which the interest of making them as short and simple as possible.
It's the audiophile myth that DBT somehow dulls the listener's senses of discriminating subtle differences. There are cases where the listeners were hearing difference between expensive audio cables and cheap audio cables when told which one is being used despite listening to the same set of cables. In such case they were hearing the difference in their own minds just by being told which cables are used. Often the subjective side ignore or are unaware of the psychology aspect of sound playback system.

And this is my opinion, and the reason for my preference in simple blind. Not the same as a "conclusion". i'm not hunting for some absolute truth in this "make believe" game we call "hifi". Truth that i never met in my long professional life.
In sound playback system, the term "hi-fi" isn't what you think it is.
 
It's the audiophile myth that DBT somehow dulls the listener's senses of discriminating subtle differences.
Myth ? Please, provide proofs. (ah ah)

There are cases where the listeners were hearing difference between expensive audio cables and cheap audio cables when told which one is being used despite listening to the same set of cables.
We are not responsible of other people's illusions or phantasms. And I have better things to do than listen to "cables".

In sound playback system, the term "hi-fi" isn't what you think it is.
Really ? You do know what i "think" ?
A good example of scientific spirit. probably the cause of your taste for blindness. ;-)
 
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Another heresy. I've decided that I'm fed up reaching round the back of things to plug in so preamp rebuild will end up with a couple of db25 connectors and umbilicals. Just where to put the patch panels to avoid the evil stare...
My amps, pre and power supply all have connections on the front, ugly but SO practical 😀

The DCX2496 is suspended vertically so the connections are on the bottom, I kid you not
 
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Myth ? Please, provide proofs. (ah ah)

I am not responsible of other people's illusions or phantasms.
It's you who stated on post #13749 that "Double blind is not optimal", "it requests a too complex process of recognition", insufficient to discriminate subtle differences". The onus is on you to back it up with proof. Without proof, it's a myth.
Really ? You do know what i "think" ?
A good example of scientific spirit. probably the cause of your taste for blindness. ;-)
I know what you wrote.
And this is my opinion, and the reason for my preference in simple blind. Not the same as a "conclusion". i'm not hunting for some absolute truth in this "make believe" game we call "hifi". Truth that i never met in my long professional life.
 
It's the audiophile myth that DBT somehow dulls the listener's senses of discriminating subtle differences. There are cases where the listeners were hearing difference between expensive audio cables and cheap audio cables when told which one is being used despite listening to the same set of cables. In such case they were hearing the difference in their own minds just by being told which cables are used. Often the subjective side ignore or are unaware of the psychology aspect of sound playback system.


In sound playback system, the term "hi-fi" isn't what you think it is.

You're a myth.

DBT have proven to be useless. Utterly useless. They don't help anyone buy a stereo, and they don't help anyone sell one either.
 
Over the weekend, I actually interacted with REAL ANALOG ENGINEERS at the Analog Aficionados conference that happens in Silicon Valley once a year. It remains the main social meeting of analog designers in Silicon Valley, and has been for many years.
Unfortunately, this year, Scott Wurcer, Barrie Gilbert and Bob Cordell did not show up, but we muddled on anyway.
Only a couple of other audio designers were there. Kirkwood Rough (of DIY) and Keith O. Johnson (Spectrol and Reference Recordings) were the only two who actually design audio that I know. However there were many others including authors of textbooks on electronics were there to talk to. Still, I am getting a little too old (77) to really enjoy standing around in a loud room. I almost needed earplugs, it was so loud. (really live room) I probably will not attend again, but let's see how I feel next year. '-)
 
My amps, pre and power supply all have connections on the front, ugly but SO practical 😀

The DCX2496 is suspended vertically so the connections are on the bottom, I kid you not


This would seem to also get around the rather garish front panel. I need to mod my miniDSP as the stock LEDs are horrid not quite white and way too bright and in direct line of sight.



Child resistant hifi shelving has it's drawbacks.
 
Scott,

As usual....

uA741s are opamps.
uA741s do sound bad.
Therefore opamps do sound bad. 😉

Or:
uA741s sound bad
LM741s sound bad
MC741s sound bad
Therefore by induction all opamps sound bad.

Or:
NE5534 opamps sound bad when the supply voltage is less than 3 volts. They also sound bad when the rails exceed 25 volts. Audio gear can run with rails from 1.5 volts to greater that 1,200 volts. So obviously for most systems they sound bad.

These are measurable results, so opinion is not applicable. 😉
 
This would seem to also get around the rather garish front panel. I need to mod my miniDSP as the stock LEDs are horrid not quite white and way too bright and in direct line of sight.
True, it's at just the right height I can't see any of the illuminations. I put a piece of black tape over the bright blue LED on the front of my TV to tell me it was on, I mean ON not standby 🙄
 
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