Solid state audio amplifier emulating a tube audio amplifier
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United States of America Patent
Stats
-
Nov 14, 1995
Grant Date -
N/A
app pub date -
Jan 18, 1994
filing date -
Jan 17, 1991
priority date (Note) -
Expired
status (Latency Note)
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Abstract
A solid state audio amplifier for connection with a loudspeaker cabinet or emulation thereof to provide amplification characteristics emulating in frequency response those of a valve audio amplifier driving a loudspeaker cabinet. The loudspeaker cabinet comprises a loudspeaker drive and its enclosure. The frequency response of the audio amplifier exhibits a low frequency resonant peak in gain representing the fundamental resonance of the loudspeaker cabinet and a monotonic increase in gain at higher frequency associated with the impedance provided voice coil inductance of the loudspeaker cabinet. The audio amplifier comprises an amplifier and gain control circuitry associated therewith. The amplifier comprises a differential amplifier and the gain control circuitry comprises a impedance network connected in feedback. The impedance network comprises a tuned circuit connected to create the low frequency resonant peak in gain and a reactance providing the increase in gain at higher frequency. The tuned circuit comprises a capacitance and a gyrator circuit simulating an inductance and the reactance comprises a capacitance.
First Claim
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- 15 United States
- 10 France
- 8 Japan
- 7 China
- 5 Korea
- 2 Other
Patent Owner(s)
| Patent Owner | Address | |
|---|---|---|
| MARSHALL AMPLIFICATION PLC | DENBIGH ROAD DENBIGH INDUSTRIES ESTATE BLETCHLEY MILTON KEYNES MK1 1DQ |
International Classification(s)
Inventor(s)
| Inventor Name | Address | # of filed Patents | Total Citations |
|---|---|---|---|
| Keir, Bruce | Milton Keynes, GB | 2 | 11 |
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| Fee | Large entity fee | small entity fee | micro entity fee | due date |
|---|
| Fee | Large entity fee | small entity fee | micro entity fee |
|---|---|---|---|
| Surcharge after expiration - Late payment is unavoidable | $700.00 | $350.00 | $175.00 |
| Surcharge after expiration - Late payment is unintentional | $1,640.00 | $820.00 | $410.00 |
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