US2452499A - Amplifying circuit arrangement - Google Patents

Amplifying circuit arrangement Download PDF

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Publication number
US2452499A
US2452499A US704122A US70412246A US2452499A US 2452499 A US2452499 A US 2452499A US 704122 A US704122 A US 704122A US 70412246 A US70412246 A US 70412246A US 2452499 A US2452499 A US 2452499A
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US
United States
Prior art keywords
frequency
tube
transformer
reproducer
cathode
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US704122A
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English (en)
Inventor
Siezen Gerrit Jan
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hartford National Bank and Trust Co
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Hartford National Bank and Trust Co
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Filing date
Publication date
Application filed by Hartford National Bank and Trust Co filed Critical Hartford National Bank and Trust Co
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Publication of US2452499A publication Critical patent/US2452499A/en
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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03G—CONTROL OF AMPLIFICATION
    • H03G5/00—Tone control or bandwidth control in amplifiers
    • H03G5/02—Manually-operated control
    • H03G5/04—Manually-operated control in untuned amplifiers
    • H03G5/06—Manually-operated control in untuned amplifiers having discharge tubes
    • H03G5/08—Manually-operated control in untuned amplifiers having discharge tubes incorporating negative feedback
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F1/00—Details of amplifiers with only discharge tubes, only semiconductor devices or only unspecified devices as amplifying elements
    • H03F1/34—Negative-feedback-circuit arrangements with or without positive feedback
    • H03F1/36—Negative-feedback-circuit arrangements with or without positive feedback in discharge-tube amplifiers
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/20—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers
    • H03F3/22—Power amplifiers, e.g. Class B amplifiers, Class C amplifiers with tubes only
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R3/00—Circuits for transducers, loudspeakers or microphones
    • H04R3/12—Circuits for transducers, loudspeakers or microphones for distributing signals to two or more loudspeakers
    • H04R3/14—Cross-over networks
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R5/00—Stereophonic arrangements
    • H04R5/04—Circuit arrangements, e.g. for selective connection of amplifier inputs/outputs to loudspeakers, for loudspeaker detection, or for adaptation of settings to personal preferences or hearing impairments

Definitions

  • the invention relates to the acoustical reproduction of electrically transmitted oscillations, and it particularly pertains to reproduction in a plurality of overlapping acoustical ranges by means of a plurality of acoustical reproducers.
  • Fig. l which comprises an amplifying tube l, the anode circuit of which includes two transformers T1 and T2 which feed a high pitched sound and a bass tone loudspeaker Li and L2 respectively,
  • the primary inductance of T1 is given a comparatively low value and a condenser C is connected in parallel with the primary winding of T2.
  • the trans former T2 transmitting the frequency-band ii of the bass tones; these bands partly overlap each other in the proximity of the separating fre quency f5.
  • the separating frequency is may, for example, amount to about 30-0 C./S.
  • the circuit-arrangement should be proportioned to be such that the total frequency characteristic curve becomes flat, 1. e. that at a control Voltage which is constant for all frequencies and set up at the grid of tube l, the total acoustic power radiated by the loudspeakers is constant throughout the frequency range to be reproduced (equalization condition).
  • the total anode impedance throughout the frequency range should be practically real and independent with respect to frequency, and should have a definite value prescribed for the tube (adaptation condition).
  • the invention is based on the recognition that, if the electro-acoustic outputs of the loudspeakers are different, which is usually the case in practice, because they are of different kinds, it is not possible to fulfill both of these two conditions at the same time and that, if the anode impedance is made real and independent with respect to frequency throughout the frequency range to be reproduced, the frequency characteristic curve is not flat. in other words that linear distortion occurs.
  • this distortion is obviated by providing means by which the oscillations supplied to the control-grid circuit of the amplifying tube are distorted in such -manner that the sound vibrations to be reproduced by the loudspeakers are reproduced practically without distortion.
  • Fig. 1 is a schematic diagram of a prior art circuit arrangement
  • Fig. 2 is a frequency response diagram of the arrangement shown in Fig. 1,
  • Fig. 3 is a schematic diagram of the equivalent circuit of the arrangement shown in Fig. 1 from which the basic concept of the invention is de rived, I Fig is a frequency response diagram based on the equivalent circuit of Fig. 3,
  • Fig. 5 is a schematic diagram of a circuit arrangement according to the invention.
  • Fig. 6' is a schematic diagram of an alternate embodiment of a circuit arrangement according to the invention.
  • Fig. 3 there is shown the equivalent circuit of the circuit arrangement shown in Fig. 1, in which it has been assumed that the stray inductances and the losses of the transformers T1 and T2 are negligibly small and that the loudspeaker impedances may be regarded as resistances Brand R2 respectively.
  • the substitute impedance Z1 of transformer T1 having a transformation ratio nizL and, as has been stated above, a low primary inductance, and of the loudspeaker L1 then consists of the parallel-connection of an inductance L and a resistance n iRi.
  • ia represents the anode current of the tube i. If this current is constant for all frequencies, which is the case at a constant control-grid voltage if the internal resistance of tube l is sufiiciently high relatively to the total anode impedance Z1+Z2, the equalization condition may be expressed as follows:
  • this distortion is obviated by giving the control-voltage, which is supplied to the grid of tube I, an opposite distortion, for example by supplying the oscillations to be amplified to the grid through a network which brings about a distortion contrary to that represented by the curve A and B respectively.
  • this network may, for example, consist of a resistance connected in series with an inductance between grid and cathode and in the second case of a resistance in series with a condenser,
  • a similar result is obtainable by means of a negative feed-back varying with frequency by including, in the manner illustrated in Fig. 5, a, resistance R1, which is connected in parallel with a condenser C1, in the cathode-lead of the amplifying tube which permits the distortion represented by curve A in Fig. 4 to be eliminated.
  • the condenser C1 is replaced by an inductance coil.
  • the negative feed-back varying with frequency has the advantage that at the same time the nonlinear distortion issuppressed.
  • a negative feed-back can be obtained by providing the transformers T1 and T2 with additional negative feed-back windings having appropriate transformation ratios.
  • An amplifier circuit arrangement for operating a high frequency reproducer in conjunction with a low frequency reproducer having different electro-acoustic characteristics for reproducing a given band of frequencies comprising an electron discharge tube having an anode, a control grid and a cathode, means to apply a signal voltage having a frequency within said band of frequencies between the control grid and cathode of said tube, a high frequency reproducer, a low frequency reproducer having different electro-acoustical characteristics than said high frequency reproducer, a first transformer having a primary winding and a secondary winding proportioned for optimum transfer of energy to said high frequency reproducer and being coupled thereto, a second transformer having a primary winding and a secondary winding proportioned for optimum transfer of energy to said low frequency reproducer and being coupled thereto, means to connect the primary windings of said transformers in series between the anode and the cathode of said tube, a capacitor shunting the primary winding of said second transformer, said series-shunt circuit having values of inductance
  • An amplifier circuit arrangement for operating a high frequency reproducer in conjunction with a low frequency reproducer having different electro-acoustic characteristics for reproducing a given band of frequencies comprising an electron discharge tube having an anode, a control grid and a cathode, means to apply a signal voltage of a plurality of frequencies within said band of frequencies between the control grid and cathode of said tube, a high frequency reproducer, a low frequency reproducer having different electro-acoustical characteristics than said high frequency reproducer, a: first transformer having a primary winding and a secondary winding proportioned for optimum transfer of energy to said high frequency reproducer and being coupled thereto, a second transformer having a primary winding and a secondary winding proportioned for optimum transfer of energy to said low frequency reproducer and being coupled thereto, means to connect the primary windings of said transformers in series between the anode and the cathode of said tube, a capacitor shunting the primary winding of said second transformer, said series-shunt circuit having values
  • An amplifier circuit arrangement for operating a high frequency reproducer in conjunction with a low frequency reproducer having different electro-acoustic characteristics for reproducing a given band of frequencies comprising an electron discharge tube having an anode, a control grid and a cathode, means to apply a signal voltage having a frequency within said band of frequencies between the control grid and cathode of said tube, a high frequency reproducer, a low frequency reproducer having different electro-acoustical characteristics than said high frequency reproducer, a first transformer having two primary windings, a.
  • a second transformer having a center tapped primary winding, a feedback winding and a secondary winding proportioned for optimum transfer of energy to said low frequency reproducer and being coupled thereto, means to connect the primary windings of said transformer in series between the anode and the cathode of said tube,-' the primary winding of said second transformer being interposed between the two primary windings of said first transformer, a capacitor shunting the primary winding of said second transformer, said series-shunt circuit having values of inductance and capacity at which the circuit is substantially independent of frequency throughout said band of frequencies, and means to connect said feedback windings in series between the grid and cathode of said tube to apply a feedback voltage in opposition to said signal voltage to produce an acoustic output substantially proportional to said signal voltage.
  • An amplifier circuit arrangement for operating a high frequency reproducer in conjunction with a low frequency reproducer having different electro-acoustic characteristics for reproducing a given band of frequencies comprising a first electron discharge tube having an anode, a control grid and a cathode, a second electron discharge tube having an anode and a cathode connected to the cathode of said first tube, means to apply a signal voltage having a frequency within said band of frequencies between the control grid and cathode of said first tube, a high frequency reproducer, a low frequency reproducer having different electro-acoustical characteristics than said high frequency reproducer,
  • a first transformer having two primary windings, a feedback winding and a secondary winding proportioned for optimum transfer of energy to said high frequency reproducer and being coupled thereto
  • a second transformer having a center tapped primary winding, a feedback winding, and a secondary winding proportioned for optimum transfer of energy to said low frequency reproducer and being coupled thereto

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Otolaryngology (AREA)
  • Amplifiers (AREA)
US704122A 1945-08-03 1946-10-18 Amplifying circuit arrangement Expired - Lifetime US2452499A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NL254963X 1945-08-03

Publications (1)

Publication Number Publication Date
US2452499A true US2452499A (en) 1948-10-26

Family

ID=19781259

Family Applications (1)

Application Number Title Priority Date Filing Date
US704122A Expired - Lifetime US2452499A (en) 1945-08-03 1946-10-18 Amplifying circuit arrangement

Country Status (5)

Country Link
US (1) US2452499A (de)
BE (1) BE467997A (de)
CH (1) CH254963A (de)
FR (1) FR936806A (de)
GB (1) GB618789A (de)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1012643B (de) * 1955-05-23 1957-07-25 Loewe Opta Ag Niederfrequenzverstaerker-Anordnung mit mehreren Lautsprechern oder Lautsprechergruppen
US3067390A (en) * 1959-10-07 1962-12-04 Optimation Inc Low level frequency dividing network
US3416088A (en) * 1963-10-29 1968-12-10 Rank Bush Murphy Ltd Electrical signal amplifier
USRE31228E (en) * 1967-12-04 1983-05-03 Bose Corporation Loudspeaker system

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1635959A (en) * 1923-02-05 1927-07-12 Rca Corp Means for reproducing sound
US1674683A (en) * 1925-03-31 1928-06-26 Lorenz C Ag Arrangement for uniform electrical sound transmission
US1698269A (en) * 1926-10-29 1929-01-08 Konheim Harvey Method of reproducing electrical oscillations and apparatus therefor
US1711529A (en) * 1923-05-14 1929-05-07 Signal Ges Mit Beschraenkter H Multiple-range sound-transmitting system
US1760821A (en) * 1927-10-19 1930-05-27 Leon F Douglass Amplifying and reproducing system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1635959A (en) * 1923-02-05 1927-07-12 Rca Corp Means for reproducing sound
US1711529A (en) * 1923-05-14 1929-05-07 Signal Ges Mit Beschraenkter H Multiple-range sound-transmitting system
US1674683A (en) * 1925-03-31 1928-06-26 Lorenz C Ag Arrangement for uniform electrical sound transmission
US1698269A (en) * 1926-10-29 1929-01-08 Konheim Harvey Method of reproducing electrical oscillations and apparatus therefor
US1760821A (en) * 1927-10-19 1930-05-27 Leon F Douglass Amplifying and reproducing system

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1012643B (de) * 1955-05-23 1957-07-25 Loewe Opta Ag Niederfrequenzverstaerker-Anordnung mit mehreren Lautsprechern oder Lautsprechergruppen
US3067390A (en) * 1959-10-07 1962-12-04 Optimation Inc Low level frequency dividing network
US3416088A (en) * 1963-10-29 1968-12-10 Rank Bush Murphy Ltd Electrical signal amplifier
USRE31228E (en) * 1967-12-04 1983-05-03 Bose Corporation Loudspeaker system

Also Published As

Publication number Publication date
BE467997A (de)
CH254963A (fr) 1948-05-31
FR936806A (fr) 1948-07-30
GB618789A (en) 1949-02-28

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