John Curl's Blowtorch preamplifier part II

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I am going to tell the story about 'Chips for Chumps' warts and all!
It was very tiresome for me to be attacked, WITHOUT any direct ability to respond. I was both blindsided and badmouthed by the article, but here goes:
At a CES some years ago, I was sitting in a small cafe waiting for the music to start. Someone I have known for more than two decades came over to sit down with me. He is known to like 'tweaks and mods' and has a degree in physical optics or some such.
He pulls this plastic 'chip' out of his pocket and tells me that it makes CD's sound better. I listen politely, but then I said something like: 'It is too early in the evening for this' (implying that I did not have enough alcohol in me yet to even consider it).
Then, the next day, at a free lunch, I looked around for a seat, and the same guy (with the chip in his pocket ) had an empty space next to him, so I sat down to have my lunch and again converse. He introduced me to his associate, David Glacklin, a PhD in Physics who worked at the time at JPL and sometimes with NASA. David, like many here, also had an interest in audio, and was a music reviewer (of all things) for 'Positive Feedback Online'. Well, mostly we talked about NASA, fixing the space telescope, and to some degree the chip. One does not get a chance like this very often to talk to someone who is on the 'inside' of NASA and I jumped at the opportunity.
After lunch, I had to report back to my listening room, where we had a system set up that amounted to about $50,000. Including a CTC Blowtorch, JC-1 power amps and probably Roger West Electrostatic speakers. We had a custom modified CD player that was originally designed by Demian Martin, and worked over by a guy from Motorola. It is one of the best CD players I have ever used, I wish that I had grabbed one when it was possible to buy one, used. Oh well.
In any case, our equipment was working well, we were very proud of the sound, and willing to take on just about anybody around. That is why we go to these shows.
In any case, a chip gets dropped off for us to try. We did not purchase it, it was just a sample. We were uncertain if it would work, but what the heck.
We were shown how to use it, and I tried an A-B test. Did I hear a difference? I think so! But I would not bet my life on it. Bob and I tried a few CDs and then put the device aside. In fact, it wound up in a kitchen drawer and left onsite. The effect appeared small, like so many 'tweaks and mods' and we did not pursue it, because it was relatively expensive for what it did. That was all there was to it.
Now, did I hear a difference, or did I just imagine it? I really don't know for sure, and neither does anyone else. However, Jim Austin got online on another website and we had a debate about it. I said that I heard a difference, and he said it was impossible for anything like that to make a difference, so I must be crazy, yet he would NOT listen to it, himself. Why bother? It should have been left in the dust, BUT Jim Austin just had to write 'Chips for Chumps' naming me as some sort of fool, and he completely blindsided me on this. Both Charles Hansen and I then took him to task for his arrogance, etc. when he had NOT even tried the chip.
Now, I have to hear about this, over and over. It gets old afterwhile.
 
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chips

I am going to tell the story about 'Chips for Chumps' warts and all!
It is very tiresome for me to be attacked, WITHOUT any direct ability to respond. I was both blindsided and badmouthed by the article, but here goes:
At a CES some years ago, I was sitting in a small cafe waiting for the music to start. Someone I have known for more than two decades came over to sit down with me. He is known to like 'tweaks and mods' and has a degree in physical optics or some such.
He pulls this plastic 'chip' out of his pocket and tells me that it makes CD's sound better. I listen politely, but then I said something like: 'It is too early in the evening for this' (implying that I did not have enough alcohol in me yet to even consider it).
Then, the next day, at a free lunch, I looked around for a seat, and the same guy (with the chip in his pocket ) had an empty space next to him, so I sat down to have my lunch and again converse. He introduced me to his associate, David Glacklin, a PhD in Physics who worked at the time at JPL and sometimes with NASA. David, like many here, also had an interest in audio, and was a music reviewer (of all things) in 'Positive Feedback Online'. Well, mostly we talked about NASA, fixing the space telescope, and to some degree the chip. One does not get a chance like this very often to talk to someone who is on the 'inside' of NASA and I jumped at the opportunity.
After lunch, I had to report back to my listening room, where we had a system set up that amounted to about $50,000. Including a CTC Blowtorch, JC-1 power amps and probably Roger West Electrostatic speakers. We had a custom modified CD player that was originally designed by Demian Martin, and worked over by a guy from Motorola. It is one of the best CD players I have ever used, I wish that I had grabbed one when it was possible to buy one, used. Oh well.
In any case, our equipment was working well, we were very proud of the sound, and willing to take on just about anybody around. That is why we go to these shows.
In any case, a chip gets dropped off for us to try. We did not purchase it, it was just a sample. We were uncertain if it would work, but what the heck.
We were shown how to use it, and I tried an A-B test. Did I hear a difference? I think so! But I would not bet my life on it. Bob and I tried a few CDs and then put the device aside. In fact, it wound up in a kitchen drawer and left onsite. The effect appeared small, like so many 'tweaks and mods' and we did not pursue it, because it was relatively expensive for what it did. That was all there was to it.
Now, did I hear a difference, or did I just imagine it? I really don't know for sure, and neither does anyone else. However, Jim Austin got online on another website and we had a debate about it. I said that I heard a difference, and he said it was impossible for anything like that to make a difference, so I must be crazy, yet he would NOT listen to it, himself. Why bother? It should have been left in the dust, BUT Jim Austin just had to write 'Chips for Chumps' naming me as some sort of fool, and he completely blindsided me on this. Both Charles Hansen and I then took him to task for his arrogance, etc. when he had NOT even tried the chip.
Now, I have to hear about this, over and over. It gets old afterwhile.

The quantum dots are not organized well enough in your chip John....
:cool:
 
I want to make it very clear, that I could care less about the 'chip'. I have never seen one since that day at the CES. Still, I will NOT condemn something, just because it doesn't make much sense within my academic background. I don't know everything, so I keep an open mind about what is possible. It works for me!
 
Yes, I agree, the AD844 are one of the best kept secrets in audio. I used them in my error correction amp as precision gain-of-one-without-feedback.

You can set the gain with a single resistor and get an open loop buffer to boot.
You remember the AD846? Almost the same except that the max lin current for the transconductance output was 10mA in stead of 1mA for the '844. Discontinued, of course.

jan didden

Thanks Jan, I had read bits and pieces about the AD844 but obviously did not look close enough, or rather long enough for that matter.
 
I want to make it very clear, that I could care less about the 'chip'. I have never seen one since that day at the CES. Still, I will NOT condemn something, just because it doesn't make much sense within my academic background. I don't know everything, so I keep an open mind about what is possible. It works for me!


Did you read the white paper? Do you think it was written seriously? The claims amount to transmutation of elements at a distance with no exchange of energy. Alchemy.
 
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If I'm not mistaken, you built a homebrew discrete JFET phono stage with zero feedback one time. I guess you don't use it any more as you have likely switched to digital.

But if you still have your vinyl rig, try comparing your own ancient device against the modern IC's that ADI sells. Then tell me that op-amps aren't mid-fi. If I'm wrong, ADI will sell a lot of IC's this year...

Just as I don't understand "high-end" designers that put pre-packaged class-D modules in their power amps, I don't understand why someone would use pre-packaged IC op-amps in other parts of their system.

Well, I have to take back part of that last statement. I actually do use 3-pin voltage regulators, because they are cheap, simple, and easy to use -- but only for non-critical digital circuits such as the display or the display uC. If I ever start running them in critical applications, you can take away my "high-end" license and issue me a mid-fi citation.

This is absolute nonsense. Period.
 
Mmmm, have to disagree with you a bit, Bonsai. "High end" is a cultural term, rather than a technical one. Part of the ritual of High End is having folks from certain magazines play with your gear, then write a story about it. This playing is always done with full knowledge of what they're playing with- products are rarely (if ever) evaluated on the basis of sound alone.

John's anecdote is a perfect example- he used an op amp at the input of one of his high end products. The magazine writer saw it, decided that this compromised the sound (there's no indication that he tried to verify that there was actually a sonic detriment), and wrote a negative review. You'll never see John (or by extension, Charles) try that one again! That is indeed a cultural violation that will cause the "high end" license to be suspended.
 
Have you compared the distortion of an RC network versus that of an LCR network? Notice that I wrote "distortion to speak of".

The Allnic phono stage measures less than .3% distortion at one volt out with a gain of 66dB. The filter is accurate ±.5 dB.

John
 
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