John Curl's Blowtorch preamplifier part II

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A reminder of design differences. These are two different phono designs that do almost exactly the same thing, but one is discrete, the other IC. The discrete unit is about 6dB quieter. They sound somewhat different too, even though they may use the same EQ caps and resistors.
 

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I can not hear better then 1% harmonic distortion, exponential decreasing.
I landed in the middle group at the Klippel website.
There is a distortion test you can share on KLIPPEL
I do hear nothing above 16kHz althoug doctors detect activity in my brain when high frequencies over 20kHz where inserted into the signal.
I am super sensitive to hum and hiss. I even go to my speakers and listen on the tweeter.
My room has a self noise of 32dB at the listening seat so i am perfectly happy with the dynamic range of CD.
One of my engineers measured over 400 CDs and unfortunately only two had a meager 14Bit.
 
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Having meet most of the reviewers at the two big underground mag and been in the same listening room with them. Davidl your comments may look that way but you will have a hard time proving them beyond a shadow of a doubt. Reviews are some one thoughts and views on a product not fact. I am not saying I agree with their view of much of the equipment . However libelous comment are not a wise thing to do.
 
I have a substantial C5 hole between ca. 2 to 5kHz. That was measued some years ago in an anechoic chamber in switzerland , typical for my age so i have the privilege that my ears did only got older but not hurt as the young people will have because of constant headphone listen.
When i EQ my system for that flaw it sounds totally unnatural.
 
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In the beginning of the MPP thread i made an MC Phono input stage with AD797.
I configured it as an instrumentation amp with several AD797 in parallel at the input.
This is a simple 1kHz harmonic measurement at -30dB ( ca. 33mV output ).
Besides the slight increase in noise i could find NOTHING.
No PIM, no IMD, no inferface distortion, no TIM no nothing !!!!
Mission acomplished. Why did i not close the thread ?
 

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