Demo Model Bob Carver Crimson 275 on display at Choice Audio in White Bear Lake, MNEmail james@choiceaudio.com to schedule a demo. If you don't have a local dealer we offer free two day shipping and no sales tax. These are fantastic amps 5 year warranty on tubes! An amplifier that actually listens to the room.
All loudspeakers generate voltage as they play. It’s generated from the driver movement necessary to reproduce music but also all loudspeakers technically “listen” to the room. Did you know that the loudspeakers in prisons are also microphones? It enables the authorities to monitor the prison’s pulse in real-time. All loudspeakers are microphones. You might not want to use one for recording but conceptually, they are microphones in reverse.
Loudspeakers are electric motors. Electric motors all kick voltage back to the power source whether it’s a loudspeaker, a refrigerator or an electric drill. Manufacturers of line conditioners have a point. Your refrigerator motor not only adds noise to the AC line, they actually send electricity back through the wall outlet. We call this Back-EMF.
With a tube type amplifier, when back EMF appears at the output terminals, to the loudspeaker the output transformer’s secondary becomes a primary! The back EMF enters the amplifier through the transformer and affects frequency response downstream. With ordinary tube type amplifiers, speaker matching becomes critical. Our amplifiers are load-invariant. Through decades of experimentation and some pretty heavy mathematics, Bob Carver has been able to use the Back-EMF to increase efficiency in the mighty SunFire subwoofers, and to improve the soundstage and openness of his full range amplifiers. This is done in a unique fashion, and, as in the case of our extended tube life, unique to our products. The amplifiers listen to the room through the loudspeakers and preserve a large soundstage. It took literally decades to get the circuit right without creating artificial coloration. If you’re concerned about naturalness, consider that Harry Pearson, the founder of Absolute Sound Magazine, noticed this phenomenon, pointed out to Bob (who already knew about it) and kept our Silver Seven amplifiers as his personal reference for years. Dick Olsher from Stereophile Magazine called this series the most important tube amplifiers in decades. Crimson 275 Stereo Tube Power Amplifier
75 x 75 watts into 8 ohms Under 2-ohm capability Tubes 12AX7 x 2 12AT7 x 1 (part of DC Restorer circuit) Tung-Sol KT120 x 4 Output Transformer Proprietary design with hand-wound, interleaved windings of copper and silver on a steel core; low leakage inductance, super wide band Four-function meter Bias setting (in conjunction with rear panel control) Tube Tester (tests at actual voltage and current conditions) Tube Matcher (cool, but not really necessary) VU Meter Rear Panel Power Switch IEC AC Input Socket Line Fuse Tube Fuse Recessed Tube Bias Control 5-way binding post outputs Gold-plated 5-way binding posts Gold-plated RCA inputs Crimson hand-rubbed finish Convection cooling Individually hand-signed by Bob Carver 275-front.png
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Specifications Rated Power:
More than 75 Watts Per Channel, both channels driven at eight ohms, from 20Hz to 20kHz with no more than 1% total harmonic distortion. Distortion decreases at lower levels. 4Ω 75 Watts Per Channel 8Ω 75 Watts Per Channel 16Ω 60 Watts Per Channel Frequency Response:
+0, -3dB from 16Hz to 35kHz.; Flat 20Hz – 20kHz ±0.25dB Distortion:
Less than 1.0% Power Bandwidth:
24 Hz to 28 kHz without filters Line Inputs:
Gold-plated RCAs Speaker Outputs Gold-plated 5-way binding posts Input Impedance:
100 Kohms (RCA) Gain:
29 dB (8 ohms) Tube Complement: One 12AX7, two 12AT7’s, four KT120’s (optional: KT88 or 6550) Hum and Noise:
Better than 100 dB below 75 Watts, A-weighted. Bias:
Rear panel potentiometer adjust, front panel meter Output Transformers:
Interleaved windings, super wide-band, low leakage inductance, proprietary design Source Impedance:
1.7 ohms Crossover Roll-Off Optional —3dB @ 40Hz, 6 dB per octave Color:
Sparkle Burgundy Red
Dimensions/Weight: 14" x 7" x 9.5" (W x H x D) / 19 lbs Country of Origin:
United States of America Chassis and Tube Warranty:
5 years
Specifications subject to change without notice.
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