US4528501A — Dual loudness meter and method

Claim 1

Independent Claim 184 words

A method for simultaneously displaying dual readings of equivalent loudness of peak type and average persistence type audio program material on a meter connected to a source of electrical signals carrying aid audio program, said source having control means for adjusting the strength of said signals comprising the steps of generating a first drive signal for said meter to give a visual display of instaneous peak amplitude of said signal, generating a second drive signal for said meter independently of said first drive signal and having a rise time of about 600 milliseconds to give a visual display of the average persistence of said signal, said first and second signals having the same relative gain, providing a visual readout and scale on said metering system, designating upper limit reference zones on said readout and scale, one for peak amplitudes and another for average persistence, said reference zones having separation of 12-14 dB, and adjusting the program level with the control means so that one of the peak or the persistence displays reaches its respective reference zone without the other exceeding its respective reference zone.

Claim 2

Independent Claim 184 words

A method for simultaneously displaying dual readings of equivalent loudness of peak type and average persistence type audio program material on a meter connected to a source of electrical signals carrying aid audio program, said source having control means for adjusting the strength of said signals comprising the steps of generating a first drive signal for said meter to give a visual display of instaneous peak amplitude of said signal, generating a second drive signal for said meter independently of said first drive signal and having a rise time of about 600 milliseconds to give a visual display of the average persistence of said signal, said first and second signals having the same relative gain, providing a visual readout and scale on said metering system, designating upper limit reference zones on said readout and scale, one for peak amplitudes and another for average persistence, said reference zones having separation of 12-14 dB, and adjusting the program level with the control means so that one of the peak or the persistence displays reaches its respective reference zone without the other exceeding its respective reference zone.

Claim 3

Dependent Claim 28 words

The method as in claim 1 further including designating a warning or reference region on said indicator scale for each of said peak and persistence scale upper limits.

Claim 4

Dependent Claim 27 words

The method as in claim 1 further including the step of blanking said indicator from reading peak signal values in the range of said persistence reference zone.

Claim 5

Dependent Claim 55 words

The method as in claim 1 further including the steps of setting said peak signal to an instantaneous and decay time of about 0.8-1.0 seconds and said persistence signal to a decay time of about 1 second to 1.3 seconds, and setting in said peak decay time to be shorter than said persistence decay time.

Claim 6

Dependent Claim 39 words

The method as in claim 1 further including the step of summing two channels of stereo signals by combining the vector sum of the stereo signals to form a single signal and applying said single signal to said meter.

Claim 7

Independent Claim 193 words

An apparatus for simultaneously displaying dual readings of equivalent loudness of peak type and average persistence type audio program material on a meter connected to a source of electrical signals carrying said audio program, said source having control means for adjusting the strength of said signals comprising means for generating a first drive signal for said meter to give a visual display of instantaneous peak amplitude of said signal, means for generating a second drive signal for said meter independently of said first drive signal and having a rise time of about 600 milliseconds to give a visual display of the average persistence of said signal, said first and second signal generating means having the same relative gain, means for providing a visual readout and scale on said metering system including means designating upper limit reference zones on said readout and scale, one for peak amplitudes and another for average persistence, said reference zones having a separation of 12-14 dB, and means for adjusting program level with the control means so that one of the peak or the persistence level reaches its respective reference zone without the other exceeding its respective reference zone.

Claim 8

Independent Claim 193 words

An apparatus for simultaneously displaying dual readings of equivalent loudness of peak type and average persistence type audio program material on a meter connected to a source of electrical signals carrying said audio program, said source having control means for adjusting the strength of said signals comprising means for generating a first drive signal for said meter to give a visual display of instantaneous peak amplitude of said signal, means for generating a second drive signal for said meter independently of said first drive signal and having a rise time of about 600 milliseconds to give a visual display of the average persistence of said signal, said first and second signal generating means having the same relative gain, means for providing a visual readout and scale on said metering system including means designating upper limit reference zones on said readout and scale, one for peak amplitudes and another for average persistence, said reference zones having a separation of 12-14 dB, and means for adjusting program level with the control means so that one of the peak or the persistence level reaches its respective reference zone without the other exceeding its respective reference zone.

Claim 9

Dependent Claim 26 words

The apparatus as in claim 6 further including means for blanking said indicator from reading peak signal values in the range of said persistence reference zone.

Claim 10

Dependent Claim 57 words

The apparatus as in claim 7 further including means for setting said peak signal to have an instantaneous decay time of about 0.8-1.0 seconds and means for setting said persistence signal to have a decay time of about 1.0 second to 1.3 seconds, said peak decay being set to a value less than said persistence decay time.

Claim 11

Dependent Claim 31 words

The apparatus as in claim 7 further including means for summing two channels of stereo information to produce a single output, means for applying said single output to drive said meter.

Claim 12

Dependent Claim 39 words

The apparatus as in claim 6 further including means forming a peak signal warning indicator and means forming a persistence signal warning indicator said persistence warning indicator being 12-14 dB lower on the scale than said peak warning indicator.

Claim 13

Dependent Claim 75 words

The apparatus as in claim 6 in which said readout includes a series of LED indicators comprising said covering a range from about -25 dB to +14 dB and arranged in an increasing series thereof, said LED indicators forming a single strand adapted to be activated by either the peak detection or the persistence detection circuit, and means for disabling the peak detection circuit whenever it would activate the reference zone of said persistence scale.

Claim 14

Dependent Claim 29 words

The apparatus as in claim 6 further in which the peak detection circuit drives the LED's to a higher light intensity output in the presence of the persistence signal.

Claim 15

Dependent Claim 33 words

The apparatus of claim 11 further in which said LED indicators are a sufficient number and said detection circuits are constructed in a range as to provide for a 1 dB spacing therebetween.

Claim 16

Dependent Claim 41 words

The apparatus of claim 6 further in which said scale visual field is arcuate, being curved to droop downwardly at its extreme ends and is adapted to be read from left to right with the higher values thereof at the right.

Claim 17

Dependent Claim 28 words

The apparatus as in claim 6 further including means for designating a warning region on said indicator scale for each of said peak and persistence scale upper limits.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1988-07-08	1989-01-07	1989-07-09	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1992-07-08	1993-01-07	1993-07-09	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1996-07-08	1997-01-07	1997-07-09	$7700.00	Window Closed / Lapsed

Dual loudness meter and method

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