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Old 14th July 2010, 07:55 PM   #4881
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Actually, this is rather a diversion, and relatively meaningless. Magnetic tape appears to capture a lot of low level information that appears to get lost in digitizing with a relatively low number of bits. Now, if low level information was digitized with 16 bit accuracy, rather than 1 or 2 bit accuracy, perhaps one major difference between analog and digital recording would be resolved, but that is not resolved at the moment.
I would like to point out that Doug Sax has access to some of the best digital recording equipment available, and he has an ear for the live sound as well. If digital did it 'right', he would give up on analog equipment, and even referring to it.
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Old 14th July 2010, 07:58 PM   #4882
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Guess, best-in-class analog audio circuitry is like how the lastest digital microprocessors requires hundreds of watts of power. Is there a Curl's Law?
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Old 14th July 2010, 07:59 PM   #4883
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Reality is what works. If I could operate with lower current and get the same result, I would do so.
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Old 14th July 2010, 08:02 PM   #4884
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Quote:
Originally Posted by scott wurcer View Post
I've been away a lot lately. I don't remember who, but one of the great tape recording gurus (Doug Sax or Keith Johnson) once said in print that it would probably take 256 bits to equal their tweeked 30ips recorders.
I take then they can record the big bang!
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Old 14th July 2010, 08:05 PM   #4885
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Quote:
Originally Posted by john curl View Post
Magnetic tape appears to capture a lot of low level information that appears to get lost in digitizing with a relatively low number of bits.
John Eargle, not exactly a slouch at recording, disagreed with that. But he understood what dither was about and how it worked. 16 bits sets a limit to the noise floor, but not to resolution.
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Old 14th July 2010, 08:08 PM   #4886
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I might add, that for the past 50 years, I have exclusively owned and driven 4 cylinder autos, including 4 sports cars, and 4 passenger cars. Yet, my associate, Jack Bybee drives a 12 cylinder car. (He also owns a Blowtorch). The reasons for 12 cylinders is for power and smoothness in response. It is very much the same with the Blowtorch. For the record, the major heat generating components are a dual shunt regulator, and the output stage of the Blowtorch, both circuits made of T0-220 power mosfets. To operate these devices at low milliamp levels, adds distortion, that can be easily measured.
If I could find a complementary mosfet pair that was happy at 15 ma or so, and could be easily attached to a heatsink, I would use it.
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Old 14th July 2010, 08:08 PM   #4887
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Reality is what works.
Yeah.
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Old 14th July 2010, 08:10 PM   #4888
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I disagree that dithering can add resolution when you only have one or two bits resolving the information at low levels. It only works (for me) if the information is continuous in frequency and level, like averaging.
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Old 14th July 2010, 08:12 PM   #4889
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That turns out not to be the case, as one bit systems playing music demonstrate every day. Eargle was particularly acidic toward the notion of reverb/decay suddenly dropping out in dithered systems.
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Old 14th July 2010, 11:07 PM   #4890
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Originally Posted by john curl View Post
. . . Dual shunt regulator, and the output stage of the blowtorch, both circuits made of t0-220 power mosfets.
: )


.
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