EP0312404A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Apparatus and method for improving the fidelity of audio recording on a magnetic medium
Assignee: Warner Custom Music Corp
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Filing: 1988-10-14
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Granted: —
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Expires: 2008-10-14
Abstract
Abstract Apparatus and method for improving the fidelity of audio recording on a magnetic medium in which an input signal, suitably equalized, and a variable amplitude RF bias signal are applied to a record head in a magnectic media recording system. The RF bias amplitude is controlled so as to be inversely proportional to a function of the sampled pre-emphasized input signal. The control signal is derived from within the record amplifier circuit.
Inventors
- 👤 John E. Baxter
- 👤 Michael K. Poimboeuf
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-10 02:09
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/02; G11B5/027; G11B5/035; G11B5/03
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
102 words
Apparatus for improved recording of an audio signal on a magnetic medium comprising: means for transferring information onto a magnetic recording medium; means for generating a bias signal having an initial reference level; means for producing a variable control signal for said generating means such that the amplitude of the bias signal is continuously varied in inverse proportion to the amount of high frequency components present in said audio signal; and means for providing an output signal at said means for transferring information onto a magnetic recording medium representative of the sum of said audio signal and said continuously varied bias signal.
Claim 2
Dependent Claim
102 words
Apparatus for improved recording of an audio signal on a magnetic medium comprising: means for transferring information onto a magnetic recording medium; means for generating a bias signal having an initial reference level; means for producing a variable control signal for said generating means such that the amplitude of the bias signal is continuously varied in inverse proportion to the amount of high frequency components present in said audio signal; and means for providing an output signal at said means for transferring information onto a magnetic recording medium representative of the sum of said audio signal and said continuously varied bias signal.
Claim 3
Dependent Claim
25 words
Apparatus as claimed in Claim 1, further comprising means for emphasizing the high frequency components of an audio signal to form an emphasized audio signal.
Claim 4
Dependent Claim
36 words
Apparatus as claimed in Claim 1 or 2, wherein said means for producing a variable control voltage comprises means for rectifying said audio signal and selectively de-emphasizing signals having a duration shorter than a predetermined value.
Claim 5
Dependent Claim
39 words
Apparatus as claimed in Claim 3, wherein said means for selectively de-emphasizing said signal having a duration shorter than a predetermined value is asymmetric in time with respect to its response to the attack and decay of said signals.
Claim 6
Dependent Claim
25 words
Apparatus as claimed in any preceding claim, wherein said means for generating a bias signal comprises means for stabilizing the amplitude of said bias signal.
Claim 7
Dependent Claim
23 words
Apparatus as claimed in Claim 5, wherein said means for stabilizing the amplitude of said bias signal includes a closed loop feedback scheme.
Claim 8
Dependent Claim
18 words
Apparatus as claimed in Claim 6, wherein said audio signal is excluded from said closed loop feedback scheme.
Claim 9
Independent Claim
81 words
A method for improving the fidelity of audio recording on a magnetic medium wherein a bias signal is added to an audio signal being recorded comprising: generating a bias signal having an initial reference level; producing a variable control voltage having frequency components which are limited to be above a predetermined level; and using said variable control voltage to continuously adjust the amplitude of said bias signal in inverse proportion to the quantity of high frequency components in said audio signal.
Claim 10
Independent Claim
81 words
A method for improving the fidelity of audio recording on a magnetic medium wherein a bias signal is added to an audio signal being recorded comprising: generating a bias signal having an initial reference level; producing a variable control voltage having frequency components which are limited to be above a predetermined level; and using said variable control voltage to continuously adjust the amplitude of said bias signal in inverse proportion to the quantity of high frequency components in said audio signal.
Claim 11
Dependent Claim
79 words
A method as claimed in Claim 8, further comprising, in said step of producing a variable control voltage, the steps of: filtering said audio signal to thereby produce a pre-emphasized audio signal; sampling said audio signal at the output of said means for filtering; rectifying said filtered audio signal to produce a fluctuating DC signal directly proportional to the peak values of said audio signal; and filtering said DC signal to remove components having durations below a predetermined level.
Claim 12
Dependent Claim
41 words
A method as claimed in Claim 9, wherein said step of filtering said DC signal further comprises the step of preventing short duration, high level changes in said audio signal from influencing the changes in the amplitude of said bias signal.
Claim 13
Dependent Claim
24 words
A method as claimed in Claim 10, further comprising separately accomplishing the timing of attack and decay of said component of said audio signal.
References Cited (Backward Citations)
No citation records indexed.
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